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  • 反射01 Class类的使用、动态加载类、类类型说明、获取类的信息

    0 Java反射机制

      反射(Reflection)是 Java 的高级特性之一,是框架实现的基础。

      0.1 定义

        Java 反射机制是在运行状态中,对于任意一个类,都能够知道这个类的所有属性和方法;对于任意一个对象,都能够调用它的任意一个方法和属性;这种动态获取的信息以及动态调用对象的方法的功能称为 Java 语言的反射机制。 

        一般而言,当用户使用一个类的时候,应该获取这个类,而后通过这个类实例化对象,但是使用反射则可以相反的通过对象获取类中的信息。

        通俗的讲反射就是可以在程序运行的时候动态装载类,查看类的信息,生成对象,或操作生成的对象。它允许运行中的 Java 程序获取自身的信息,自己能看到自己,就像照镜子一样。【源自gitChat】

    1 Class类的使用

      1.1 扫盲知识点

        在Java的世界里,万事万物都是对象【PS: 类也是一个对象】。

        坑01:java语言中,静态成员、普通数据类型不是对象

        技巧01:普通的数据类型虽然不是对象,但是普通的数据类型都有对应的包装类来让其转化成一个对象

        技巧02:静态的成员是属于类的而不是属于对象的,所以静态的成员不是对象

        技巧03:所有的类都是java.lang.Class的实例对象【there is a class name Class:Class类的实例就是所有的实例对象所属的类】

      1.2 Class类实例的创建

        任何一个类都是Class类的实例对象,Class类的实例对象三种表示方式;

        类也是一个实例对象,Class类的实例对象,这个对象我们称为该类的类类型;

          例如:我们创建一个名为Foo的类,Foo类就是Class类的实例对象,假设Foo类对应的Class类的实例名为c1,那么我们就称c1Foo类的类类型

          总结:类类型就是Class类的一个实例,而且一个类只能有一个类类型,也就是所一个类只能和一个Class对应;虽然可以通过三种方式创建一个Class实例,但是针对一个类而言这三种方式创建得到的Class实例都是相等的,因为一个类的类类型只能和一个Class的实例对象。(即:一个类通过三种方式创建的类类型其实是一样的)

        技巧01:不同的类对应的类类型都不一样,同理,不同的类对应的Class类实例都不一样

        技巧02:同一个类只有一个类类型,同理,同一个类只和一个Class类实例对应;所以,同一个类通过不同方式创建的类类型都是一样的

        1.2.1 利用class创建

          任何一个类都默认拥有一个名为class的静态成员变量,该类可以利用class静态成员去创建该类的类实例。

            例如:创建了一个名为Foo的类,执行 Foo.class 就会创建一个 Class 的实例,我们把得到的Class实例命名为c1,这个c1就是Foo类对应的类类型

        1.2.2 利用实例对象创建

          如果已经得到了某个类的实例,那么可以调用这个实例的成员方法getClass去创建该实例所属类的类类型

            例如:创建了一个名为Foo的类,根据Foo创建了一个Foo的实例对象foo,我们可以利用foo去调用getClass来创建Class类的一个实例c2,这个c2就是foo所属类Foo的类类型

        1.2.3 利用Class类创建

          Class类有一个静态方法forName,Class类可以利用这个静态方法创建一个Class实例;forName方法的参数是一个类的全名

            例如:创建了一个类Foo,该类的全名为 demo06_reflect.case01_class.Foo ,那么就可以利 Class.forName("demo06_reflect.case01_class.Foo")

    去创建一个Class类的实例c3,这个c3就是Foo类的类类型

    package demo06_reflect.case01_class;
    
    /**
     * @author 王杨帅
     * @create 2018-08-03 21:43
     * @desc Class的使用
     **/
    public class Demo01_Class {
    
        public static void main(String[] args) {
    
            // 创建Foo类的一个实例foo, Foo是foo的实例类型,foo是Foo的一个实例
            Foo foo = new Foo();
    
            // Class实例创建01:利用静态成员calss创建
            Class c1 = Foo.class;
    
            // Class实例创建02:利用实例成员ngetClass创建
            Class c2 = foo.getClass();
    
    //        因为一个类只和一个Class实例对应,所以结果为true
            System.out.println(c1 == c2);
    
            // Class实例创建03:利用Class类的静态成员forName创建
            try {
                Class c3 = Class.forName("demo06_reflect.case01_class.Foo");
                System.out.println(c1 == c3);
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }
    
    
        }
    
    }
    
    class Foo {
        public String name = "warrio";
        public void pirnt() {
            System.out.println("foo");
        }
    }
    View Code

      1.3 Class类实例的作用

        可以利用Class类实例去创建对应类的实例

          例如:c1Foo类对应的Class实例(即:c1Foo类的类类型),那么可以调用c1的实例方法newInstance去创建一个Foo实例foo,此时Foo类就称为foo实例的实例类型

        技巧01:通过Class实例创建该实例对应类的实例是必须进行类型转换,因为Class实例创建出来的实例类型都是Object类型的;而且还必须进行异常处理

        技巧02:Class实例对应的类必须拥有无参构造器【PS: 有参构造器会覆盖默认的无参构造器】

    package demo06_reflect.case01_class;
    
    /**
     * @author 王杨帅
     * @create 2018-08-03 21:43
     * @desc Class的使用
     **/
    public class Demo01_Class {
    
        public static void main(String[] args) {
    
            try {
                Foo foo = (Foo) Foo.class.newInstance();
                foo.print();
            } catch (InstantiationException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            }
    
        }
    
    }
    
    class Foo {
        public String name = "warrio";
        public void print() {
            System.out.println("foo");
        }
    
        public Foo() {
        }
    
        public Foo(String name) {
            this.name = name;
        }
    }
    View Code

      1.4 代码汇总

    package demo06_reflect.case01_class;
    
    /**
     * @author 王杨帅
     * @create 2018-08-03 21:43
     * @desc Class的使用
     **/
    public class Demo01_Class {
    
        public static void main(String[] args) {
    
    //        Foo实例的表示
            Foo f1 = new Foo();
    
    //        Foo也是一个实例对象【Foo类是Class类的实例对象】
    
            /**
             * 任何一个类都是Class类的实例对象,Class类的实例对象有三种表示方式
             */
    //        Class实例的表示01:任何一个类都有一个隐含的静态成员变量class
            Class c1 = Foo.class;
    
    //        Class实例的表示02:任何一个实例对象通过getClass方法就可以创建出一个Class类的实例
            Class c2 = f1.getClass();
    
            /**
             * c1 c2 表示了Foo类的类类型(class type)
             *      类也是一个实例对象,是Class类的实例对象;这个对象我们成为该类的类类型
             *      【类类型就是Class类的一个实例对象,而且一个类类型只能和一个Class的实例对应】
             */
    
    //        c1 和 c2 都代表了Foo类的类类型,一个类只可能是Class类的一个实例对象
            System.out.println(c1 == c2);
    
    //        Class实例的表示03:直接利用 Class 类的 forName 静态方法实现
            try {
                Class c3 = Class.forName("demo06_reflect.case01_class.Foo");
            } catch (ClassNotFoundException e) {
                e.printStackTrace();
            }
    
    //        04 可以利用该类的类类型创建该类的对象【通过c1/c2/c3创建Foo的实例】
    //                前提:Foo类必须拥有无参数的构造方法
            try {
                Foo f2 = (Foo) c2.newInstance();
                f2.print();
            } catch (InstantiationException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            }
    
            Class c = Foo2.class;
            System.out.println(c1 == c);
    
        }
    
    }
    
    class Foo {
        void print(){
            System.out.println("foo");
        }
    }
    
    class Foo2 {}
    View Code

    2 动态加载类

      2.1 扫盲知识点

        Class.forName("类的全名") 不仅表示了类的类类型,还代表了动态加载类;

        编译时刻加载类是静态加载类,运行时刻加载类是动态加载类 。

      2.2 静态加载测试

        2.2.1 需求

          根据主函数中的参数创建对应的实例,并调用实例的方法

        2.2.2 代码实现

    public class Office {
    
        public static void main(String[] args) {
            System.out.println("Hello Boy");
    
            if ("Word".equals(args[0])) {
                Word word = new Word();
                word.start();
            }
    
            if ("Excel".equals(args[0])) {
                Excel excel = new Excel();
                excel.start();
            }
    
        }
    
    }
    Office.java

        2.2.3 编译

          进入到存放源文件的文件夹,执行 javac "源文件名.java" 就可以对源文件进行编译

        2.2.4 编译报错原因

          在源代码中需要用到 Word 和 Excel 两个类,所以这两个类必须存在,而且必须经过编译

          技巧01:因为源代码中是利用 new 关键字进行实例创建的,这种方式是静态加载类的方式,所以用到的类必须存在而且编译好的

          技巧02:执行 javac Office.java 时会自动编译 Word.java、Excel.java 两个文件【PS: 前提是存在】

    public class Word {
        public void start() {
            System.out.println("Word start...");
        }
    }
    Word.java
    public class Excel {
        public void start() {
            System.out.println("Excel start...");
        }
    }
    Excel.java

        2.2.5 运行测试

          运行 Office 时,传入 Word 或者 Excel ,查看效果:

            例如: java Office Word  

      2.3 静态加载的缺点

        需要进行静态加载的类必须存在,如果有一个不存在的话就会导致整个代码编译失败

          例如:删掉Excel类,再次执行 javac Office.java 

      2.4 动态加载类的作用

        技巧01根据类的全名去动态加载类是在运行期间进行的

        2.4.1 需求

          根据不同的类名称去动态加载不同的类,让后调用该类的实例【PS: 这里的不同类指的是实现了同一接口的不同实现类】

        2.4.2 思路

          》定义一个OfficeAble接口,让Word和Excel都实现这个接口

          》通过Class.fromName来动态加载类得到的类类型

          》通过类类型去创建实例,将的到的实例类型指定为OfficeAble类型

          》利用多态的特性去调用实例的方法

        2.4.3 代码改进

          技巧01:动态加载用到的类需要提前编译好,不然运行时会找不到需要的文件

          技巧02:动态加载类可以根据不同的参数动态加载不同的实现类

    public interface OfficeAble {
        void start();
    }
    OfficeAble.java
    public class Word implements OfficeAble {
        public void start() {
            System.out.println("Word start...");
        }
    }
    Word.java
    public class Excel implements OfficeAble {
        public void start() {
            System.out.println("Excel start...");
        }
    }
    Excel.java
    public class OfficeBetter {
        public static void main(String[] args) {
            try {
                Class c = Class.forName(args[0]);
                OfficeAble officeAble = (OfficeAble)c.newInstance();
                officeAble.start();
            } catch (Exception e) {
                e.printStackTrace();
            }
        }
    }
    OfficeBetter.java

      2.5 动态加载使用场景

        业务功能更新,某个业务需要更新时,只需要一个重新实现了该业务接口的类,将其进行编译后,程序调用时修改调用的类名即可,这样就可以通过类的动态加载来实现局部业务的更新。

          

    3 类类型说明

      除了类拥有类类型外,基本的数据类型也拥有类类型。

      技巧01:基本类型和基本类型对应的包装类型各自都有各自的类类型

    package demo06_reflect.case03_method;
    
    /**
     * @author 王杨帅
     * @create 2018-08-05 22:25
     * @desc 基本类型和void都有类类型
     **/
    public class Demo01 {
    
        public static void main(String[] args) {
            Class c1 = int.class;
            System.out.println(c1.getName());
    
            Class c2 = Integer.class;
            System.out.println(c2.getName());
    
            Class c3 = void.class;
            System.out.println(c3.getName());
    
            Class c4 = Void.class;
            System.out.println(c4.getName());
        }
    
    }
    View Code

    4 获取类的信息

      通过一个类的类型可以获取到该类的所有信息,详情可以参见Class源码

    /*
     * Copyright (c) 1994, 2014, Oracle and/or its affiliates. All rights reserved.
     * ORACLE PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     *
     */
    
    package java.lang;
    
    import java.lang.reflect.AnnotatedElement;
    import java.lang.reflect.Array;
    import java.lang.reflect.GenericArrayType;
    import java.lang.reflect.GenericDeclaration;
    import java.lang.reflect.Member;
    import java.lang.reflect.Field;
    import java.lang.reflect.Executable;
    import java.lang.reflect.Method;
    import java.lang.reflect.Constructor;
    import java.lang.reflect.Modifier;
    import java.lang.reflect.Type;
    import java.lang.reflect.TypeVariable;
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.AnnotatedType;
    import java.lang.ref.SoftReference;
    import java.io.InputStream;
    import java.io.ObjectStreamField;
    import java.security.AccessController;
    import java.security.PrivilegedAction;
    import java.util.ArrayList;
    import java.util.Arrays;
    import java.util.Collection;
    import java.util.HashSet;
    import java.util.LinkedHashMap;
    import java.util.List;
    import java.util.Set;
    import java.util.Map;
    import java.util.HashMap;
    import java.util.Objects;
    import sun.misc.Unsafe;
    import sun.reflect.CallerSensitive;
    import sun.reflect.ConstantPool;
    import sun.reflect.Reflection;
    import sun.reflect.ReflectionFactory;
    import sun.reflect.generics.factory.CoreReflectionFactory;
    import sun.reflect.generics.factory.GenericsFactory;
    import sun.reflect.generics.repository.ClassRepository;
    import sun.reflect.generics.repository.MethodRepository;
    import sun.reflect.generics.repository.ConstructorRepository;
    import sun.reflect.generics.scope.ClassScope;
    import sun.security.util.SecurityConstants;
    import java.lang.annotation.Annotation;
    import java.lang.reflect.Proxy;
    import sun.reflect.annotation.*;
    import sun.reflect.misc.ReflectUtil;
    
    /**
     * Instances of the class {@code Class} represent classes and
     * interfaces in a running Java application.  An enum is a kind of
     * class and an annotation is a kind of interface.  Every array also
     * belongs to a class that is reflected as a {@code Class} object
     * that is shared by all arrays with the same element type and number
     * of dimensions.  The primitive Java types ({@code boolean},
     * {@code byte}, {@code char}, {@code short},
     * {@code int}, {@code long}, {@code float}, and
     * {@code double}), and the keyword {@code void} are also
     * represented as {@code Class} objects.
     *
     * <p> {@code Class} has no public constructor. Instead {@code Class}
     * objects are constructed automatically by the Java Virtual Machine as classes
     * are loaded and by calls to the {@code defineClass} method in the class
     * loader.
     *
     * <p> The following example uses a {@code Class} object to print the
     * class name of an object:
     *
     * <blockquote><pre>
     *     void printClassName(Object obj) {
     *         System.out.println("The class of " + obj +
     *                            " is " + obj.getClass().getName());
     *     }
     * </pre></blockquote>
     *
     * <p> It is also possible to get the {@code Class} object for a named
     * type (or for void) using a class literal.  See Section 15.8.2 of
     * <cite>The Java&trade; Language Specification</cite>.
     * For example:
     *
     * <blockquote>
     *     {@code System.out.println("The name of class Foo is: "+Foo.class.getName());}
     * </blockquote>
     *
     * @param <T> the type of the class modeled by this {@code Class}
     * object.  For example, the type of {@code String.class} is {@code
     * Class<String>}.  Use {@code Class<?>} if the class being modeled is
     * unknown.
     *
     * @author  unascribed
     * @see     java.lang.ClassLoader#defineClass(byte[], int, int)
     * @since   JDK1.0
     */
    public final class Class<T> implements java.io.Serializable,
                                  GenericDeclaration,
                                  Type,
                                  AnnotatedElement {
        private static final int ANNOTATION= 0x00002000;
        private static final int ENUM      = 0x00004000;
        private static final int SYNTHETIC = 0x00001000;
    
        private static native void registerNatives();
        static {
            registerNatives();
        }
    
        /*
         * Private constructor. Only the Java Virtual Machine creates Class objects.
         * This constructor is not used and prevents the default constructor being
         * generated.
         */
        private Class(ClassLoader loader) {
            // Initialize final field for classLoader.  The initialization value of non-null
            // prevents future JIT optimizations from assuming this final field is null.
            classLoader = loader;
        }
    
        /**
         * Converts the object to a string. The string representation is the
         * string "class" or "interface", followed by a space, and then by the
         * fully qualified name of the class in the format returned by
         * {@code getName}.  If this {@code Class} object represents a
         * primitive type, this method returns the name of the primitive type.  If
         * this {@code Class} object represents void this method returns
         * "void".
         *
         * @return a string representation of this class object.
         */
        public String toString() {
            return (isInterface() ? "interface " : (isPrimitive() ? "" : "class "))
                + getName();
        }
    
        /**
         * Returns a string describing this {@code Class}, including
         * information about modifiers and type parameters.
         *
         * The string is formatted as a list of type modifiers, if any,
         * followed by the kind of type (empty string for primitive types
         * and {@code class}, {@code enum}, {@code interface}, or
         * <code>&#64;</code>{@code interface}, as appropriate), followed
         * by the type's name, followed by an angle-bracketed
         * comma-separated list of the type's type parameters, if any.
         *
         * A space is used to separate modifiers from one another and to
         * separate any modifiers from the kind of type. The modifiers
         * occur in canonical order. If there are no type parameters, the
         * type parameter list is elided.
         *
         * <p>Note that since information about the runtime representation
         * of a type is being generated, modifiers not present on the
         * originating source code or illegal on the originating source
         * code may be present.
         *
         * @return a string describing this {@code Class}, including
         * information about modifiers and type parameters
         *
         * @since 1.8
         */
        public String toGenericString() {
            if (isPrimitive()) {
                return toString();
            } else {
                StringBuilder sb = new StringBuilder();
    
                // Class modifiers are a superset of interface modifiers
                int modifiers = getModifiers() & Modifier.classModifiers();
                if (modifiers != 0) {
                    sb.append(Modifier.toString(modifiers));
                    sb.append(' ');
                }
    
                if (isAnnotation()) {
                    sb.append('@');
                }
                if (isInterface()) { // Note: all annotation types are interfaces
                    sb.append("interface");
                } else {
                    if (isEnum())
                        sb.append("enum");
                    else
                        sb.append("class");
                }
                sb.append(' ');
                sb.append(getName());
    
                TypeVariable<?>[] typeparms = getTypeParameters();
                if (typeparms.length > 0) {
                    boolean first = true;
                    sb.append('<');
                    for(TypeVariable<?> typeparm: typeparms) {
                        if (!first)
                            sb.append(',');
                        sb.append(typeparm.getTypeName());
                        first = false;
                    }
                    sb.append('>');
                }
    
                return sb.toString();
            }
        }
    
        /**
         * Returns the {@code Class} object associated with the class or
         * interface with the given string name.  Invoking this method is
         * equivalent to:
         *
         * <blockquote>
         *  {@code Class.forName(className, true, currentLoader)}
         * </blockquote>
         *
         * where {@code currentLoader} denotes the defining class loader of
         * the current class.
         *
         * <p> For example, the following code fragment returns the
         * runtime {@code Class} descriptor for the class named
         * {@code java.lang.Thread}:
         *
         * <blockquote>
         *   {@code Class t = Class.forName("java.lang.Thread")}
         * </blockquote>
         * <p>
         * A call to {@code forName("X")} causes the class named
         * {@code X} to be initialized.
         *
         * @param      className   the fully qualified name of the desired class.
         * @return     the {@code Class} object for the class with the
         *             specified name.
         * @exception LinkageError if the linkage fails
         * @exception ExceptionInInitializerError if the initialization provoked
         *            by this method fails
         * @exception ClassNotFoundException if the class cannot be located
         */
        @CallerSensitive
        public static Class<?> forName(String className)
                    throws ClassNotFoundException {
            Class<?> caller = Reflection.getCallerClass();
            return forName0(className, true, ClassLoader.getClassLoader(caller), caller);
        }
    
    
        /**
         * Returns the {@code Class} object associated with the class or
         * interface with the given string name, using the given class loader.
         * Given the fully qualified name for a class or interface (in the same
         * format returned by {@code getName}) this method attempts to
         * locate, load, and link the class or interface.  The specified class
         * loader is used to load the class or interface.  If the parameter
         * {@code loader} is null, the class is loaded through the bootstrap
         * class loader.  The class is initialized only if the
         * {@code initialize} parameter is {@code true} and if it has
         * not been initialized earlier.
         *
         * <p> If {@code name} denotes a primitive type or void, an attempt
         * will be made to locate a user-defined class in the unnamed package whose
         * name is {@code name}. Therefore, this method cannot be used to
         * obtain any of the {@code Class} objects representing primitive
         * types or void.
         *
         * <p> If {@code name} denotes an array class, the component type of
         * the array class is loaded but not initialized.
         *
         * <p> For example, in an instance method the expression:
         *
         * <blockquote>
         *  {@code Class.forName("Foo")}
         * </blockquote>
         *
         * is equivalent to:
         *
         * <blockquote>
         *  {@code Class.forName("Foo", true, this.getClass().getClassLoader())}
         * </blockquote>
         *
         * Note that this method throws errors related to loading, linking or
         * initializing as specified in Sections 12.2, 12.3 and 12.4 of <em>The
         * Java Language Specification</em>.
         * Note that this method does not check whether the requested class
         * is accessible to its caller.
         *
         * <p> If the {@code loader} is {@code null}, and a security
         * manager is present, and the caller's class loader is not null, then this
         * method calls the security manager's {@code checkPermission} method
         * with a {@code RuntimePermission("getClassLoader")} permission to
         * ensure it's ok to access the bootstrap class loader.
         *
         * @param name       fully qualified name of the desired class
         * @param initialize if {@code true} the class will be initialized.
         *                   See Section 12.4 of <em>The Java Language Specification</em>.
         * @param loader     class loader from which the class must be loaded
         * @return           class object representing the desired class
         *
         * @exception LinkageError if the linkage fails
         * @exception ExceptionInInitializerError if the initialization provoked
         *            by this method fails
         * @exception ClassNotFoundException if the class cannot be located by
         *            the specified class loader
         *
         * @see       java.lang.Class#forName(String)
         * @see       java.lang.ClassLoader
         * @since     1.2
         */
        @CallerSensitive
        public static Class<?> forName(String name, boolean initialize,
                                       ClassLoader loader)
            throws ClassNotFoundException
        {
            Class<?> caller = null;
            SecurityManager sm = System.getSecurityManager();
            if (sm != null) {
                // Reflective call to get caller class is only needed if a security manager
                // is present.  Avoid the overhead of making this call otherwise.
                caller = Reflection.getCallerClass();
                if (sun.misc.VM.isSystemDomainLoader(loader)) {
                    ClassLoader ccl = ClassLoader.getClassLoader(caller);
                    if (!sun.misc.VM.isSystemDomainLoader(ccl)) {
                        sm.checkPermission(
                            SecurityConstants.GET_CLASSLOADER_PERMISSION);
                    }
                }
            }
            return forName0(name, initialize, loader, caller);
        }
    
        /** Called after security check for system loader access checks have been made. */
        private static native Class<?> forName0(String name, boolean initialize,
                                                ClassLoader loader,
                                                Class<?> caller)
            throws ClassNotFoundException;
    
        /**
         * Creates a new instance of the class represented by this {@code Class}
         * object.  The class is instantiated as if by a {@code new}
         * expression with an empty argument list.  The class is initialized if it
         * has not already been initialized.
         *
         * <p>Note that this method propagates any exception thrown by the
         * nullary constructor, including a checked exception.  Use of
         * this method effectively bypasses the compile-time exception
         * checking that would otherwise be performed by the compiler.
         * The {@link
         * java.lang.reflect.Constructor#newInstance(java.lang.Object...)
         * Constructor.newInstance} method avoids this problem by wrapping
         * any exception thrown by the constructor in a (checked) {@link
         * java.lang.reflect.InvocationTargetException}.
         *
         * @return  a newly allocated instance of the class represented by this
         *          object.
         * @throws  IllegalAccessException  if the class or its nullary
         *          constructor is not accessible.
         * @throws  InstantiationException
         *          if this {@code Class} represents an abstract class,
         *          an interface, an array class, a primitive type, or void;
         *          or if the class has no nullary constructor;
         *          or if the instantiation fails for some other reason.
         * @throws  ExceptionInInitializerError if the initialization
         *          provoked by this method fails.
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and
         *          the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class.
         */
        @CallerSensitive
        public T newInstance()
            throws InstantiationException, IllegalAccessException
        {
            if (System.getSecurityManager() != null) {
                checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
            }
    
            // NOTE: the following code may not be strictly correct under
            // the current Java memory model.
    
            // Constructor lookup
            if (cachedConstructor == null) {
                if (this == Class.class) {
                    throw new IllegalAccessException(
                        "Can not call newInstance() on the Class for java.lang.Class"
                    );
                }
                try {
                    Class<?>[] empty = {};
                    final Constructor<T> c = getConstructor0(empty, Member.DECLARED);
                    // Disable accessibility checks on the constructor
                    // since we have to do the security check here anyway
                    // (the stack depth is wrong for the Constructor's
                    // security check to work)
                    java.security.AccessController.doPrivileged(
                        new java.security.PrivilegedAction<Void>() {
                            public Void run() {
                                    c.setAccessible(true);
                                    return null;
                                }
                            });
                    cachedConstructor = c;
                } catch (NoSuchMethodException e) {
                    throw (InstantiationException)
                        new InstantiationException(getName()).initCause(e);
                }
            }
            Constructor<T> tmpConstructor = cachedConstructor;
            // Security check (same as in java.lang.reflect.Constructor)
            int modifiers = tmpConstructor.getModifiers();
            if (!Reflection.quickCheckMemberAccess(this, modifiers)) {
                Class<?> caller = Reflection.getCallerClass();
                if (newInstanceCallerCache != caller) {
                    Reflection.ensureMemberAccess(caller, this, null, modifiers);
                    newInstanceCallerCache = caller;
                }
            }
            // Run constructor
            try {
                return tmpConstructor.newInstance((Object[])null);
            } catch (InvocationTargetException e) {
                Unsafe.getUnsafe().throwException(e.getTargetException());
                // Not reached
                return null;
            }
        }
        private volatile transient Constructor<T> cachedConstructor;
        private volatile transient Class<?>       newInstanceCallerCache;
    
    
        /**
         * Determines if the specified {@code Object} is assignment-compatible
         * with the object represented by this {@code Class}.  This method is
         * the dynamic equivalent of the Java language {@code instanceof}
         * operator. The method returns {@code true} if the specified
         * {@code Object} argument is non-null and can be cast to the
         * reference type represented by this {@code Class} object without
         * raising a {@code ClassCastException.} It returns {@code false}
         * otherwise.
         *
         * <p> Specifically, if this {@code Class} object represents a
         * declared class, this method returns {@code true} if the specified
         * {@code Object} argument is an instance of the represented class (or
         * of any of its subclasses); it returns {@code false} otherwise. If
         * this {@code Class} object represents an array class, this method
         * returns {@code true} if the specified {@code Object} argument
         * can be converted to an object of the array class by an identity
         * conversion or by a widening reference conversion; it returns
         * {@code false} otherwise. If this {@code Class} object
         * represents an interface, this method returns {@code true} if the
         * class or any superclass of the specified {@code Object} argument
         * implements this interface; it returns {@code false} otherwise. If
         * this {@code Class} object represents a primitive type, this method
         * returns {@code false}.
         *
         * @param   obj the object to check
         * @return  true if {@code obj} is an instance of this class
         *
         * @since JDK1.1
         */
        public native boolean isInstance(Object obj);
    
    
        /**
         * Determines if the class or interface represented by this
         * {@code Class} object is either the same as, or is a superclass or
         * superinterface of, the class or interface represented by the specified
         * {@code Class} parameter. It returns {@code true} if so;
         * otherwise it returns {@code false}. If this {@code Class}
         * object represents a primitive type, this method returns
         * {@code true} if the specified {@code Class} parameter is
         * exactly this {@code Class} object; otherwise it returns
         * {@code false}.
         *
         * <p> Specifically, this method tests whether the type represented by the
         * specified {@code Class} parameter can be converted to the type
         * represented by this {@code Class} object via an identity conversion
         * or via a widening reference conversion. See <em>The Java Language
         * Specification</em>, sections 5.1.1 and 5.1.4 , for details.
         *
         * @param cls the {@code Class} object to be checked
         * @return the {@code boolean} value indicating whether objects of the
         * type {@code cls} can be assigned to objects of this class
         * @exception NullPointerException if the specified Class parameter is
         *            null.
         * @since JDK1.1
         */
        public native boolean isAssignableFrom(Class<?> cls);
    
    
        /**
         * Determines if the specified {@code Class} object represents an
         * interface type.
         *
         * @return  {@code true} if this object represents an interface;
         *          {@code false} otherwise.
         */
        public native boolean isInterface();
    
    
        /**
         * Determines if this {@code Class} object represents an array class.
         *
         * @return  {@code true} if this object represents an array class;
         *          {@code false} otherwise.
         * @since   JDK1.1
         */
        public native boolean isArray();
    
    
        /**
         * Determines if the specified {@code Class} object represents a
         * primitive type.
         *
         * <p> There are nine predefined {@code Class} objects to represent
         * the eight primitive types and void.  These are created by the Java
         * Virtual Machine, and have the same names as the primitive types that
         * they represent, namely {@code boolean}, {@code byte},
         * {@code char}, {@code short}, {@code int},
         * {@code long}, {@code float}, and {@code double}.
         *
         * <p> These objects may only be accessed via the following public static
         * final variables, and are the only {@code Class} objects for which
         * this method returns {@code true}.
         *
         * @return true if and only if this class represents a primitive type
         *
         * @see     java.lang.Boolean#TYPE
         * @see     java.lang.Character#TYPE
         * @see     java.lang.Byte#TYPE
         * @see     java.lang.Short#TYPE
         * @see     java.lang.Integer#TYPE
         * @see     java.lang.Long#TYPE
         * @see     java.lang.Float#TYPE
         * @see     java.lang.Double#TYPE
         * @see     java.lang.Void#TYPE
         * @since JDK1.1
         */
        public native boolean isPrimitive();
    
        /**
         * Returns true if this {@code Class} object represents an annotation
         * type.  Note that if this method returns true, {@link #isInterface()}
         * would also return true, as all annotation types are also interfaces.
         *
         * @return {@code true} if this class object represents an annotation
         *      type; {@code false} otherwise
         * @since 1.5
         */
        public boolean isAnnotation() {
            return (getModifiers() & ANNOTATION) != 0;
        }
    
        /**
         * Returns {@code true} if this class is a synthetic class;
         * returns {@code false} otherwise.
         * @return {@code true} if and only if this class is a synthetic class as
         *         defined by the Java Language Specification.
         * @jls 13.1 The Form of a Binary
         * @since 1.5
         */
        public boolean isSynthetic() {
            return (getModifiers() & SYNTHETIC) != 0;
        }
    
        /**
         * Returns the  name of the entity (class, interface, array class,
         * primitive type, or void) represented by this {@code Class} object,
         * as a {@code String}.
         *
         * <p> If this class object represents a reference type that is not an
         * array type then the binary name of the class is returned, as specified
         * by
         * <cite>The Java&trade; Language Specification</cite>.
         *
         * <p> If this class object represents a primitive type or void, then the
         * name returned is a {@code String} equal to the Java language
         * keyword corresponding to the primitive type or void.
         *
         * <p> If this class object represents a class of arrays, then the internal
         * form of the name consists of the name of the element type preceded by
         * one or more '{@code [}' characters representing the depth of the array
         * nesting.  The encoding of element type names is as follows:
         *
         * <blockquote><table summary="Element types and encodings">
         * <tr><th> Element Type <th> &nbsp;&nbsp;&nbsp; <th> Encoding
         * <tr><td> boolean      <td> &nbsp;&nbsp;&nbsp; <td align=center> Z
         * <tr><td> byte         <td> &nbsp;&nbsp;&nbsp; <td align=center> B
         * <tr><td> char         <td> &nbsp;&nbsp;&nbsp; <td align=center> C
         * <tr><td> class or interface
         *                       <td> &nbsp;&nbsp;&nbsp; <td align=center> L<i>classname</i>;
         * <tr><td> double       <td> &nbsp;&nbsp;&nbsp; <td align=center> D
         * <tr><td> float        <td> &nbsp;&nbsp;&nbsp; <td align=center> F
         * <tr><td> int          <td> &nbsp;&nbsp;&nbsp; <td align=center> I
         * <tr><td> long         <td> &nbsp;&nbsp;&nbsp; <td align=center> J
         * <tr><td> short        <td> &nbsp;&nbsp;&nbsp; <td align=center> S
         * </table></blockquote>
         *
         * <p> The class or interface name <i>classname</i> is the binary name of
         * the class specified above.
         *
         * <p> Examples:
         * <blockquote><pre>
         * String.class.getName()
         *     returns "java.lang.String"
         * byte.class.getName()
         *     returns "byte"
         * (new Object[3]).getClass().getName()
         *     returns "[Ljava.lang.Object;"
         * (new int[3][4][5][6][7][8][9]).getClass().getName()
         *     returns "[[[[[[[I"
         * </pre></blockquote>
         *
         * @return  the name of the class or interface
         *          represented by this object.
         */
        public String getName() {
            String name = this.name;
            if (name == null)
                this.name = name = getName0();
            return name;
        }
    
        // cache the name to reduce the number of calls into the VM
        private transient String name;
        private native String getName0();
    
        /**
         * Returns the class loader for the class.  Some implementations may use
         * null to represent the bootstrap class loader. This method will return
         * null in such implementations if this class was loaded by the bootstrap
         * class loader.
         *
         * <p> If a security manager is present, and the caller's class loader is
         * not null and the caller's class loader is not the same as or an ancestor of
         * the class loader for the class whose class loader is requested, then
         * this method calls the security manager's {@code checkPermission}
         * method with a {@code RuntimePermission("getClassLoader")}
         * permission to ensure it's ok to access the class loader for the class.
         *
         * <p>If this object
         * represents a primitive type or void, null is returned.
         *
         * @return  the class loader that loaded the class or interface
         *          represented by this object.
         * @throws SecurityException
         *    if a security manager exists and its
         *    {@code checkPermission} method denies
         *    access to the class loader for the class.
         * @see java.lang.ClassLoader
         * @see SecurityManager#checkPermission
         * @see java.lang.RuntimePermission
         */
        @CallerSensitive
        public ClassLoader getClassLoader() {
            ClassLoader cl = getClassLoader0();
            if (cl == null)
                return null;
            SecurityManager sm = System.getSecurityManager();
            if (sm != null) {
                ClassLoader.checkClassLoaderPermission(cl, Reflection.getCallerClass());
            }
            return cl;
        }
    
        // Package-private to allow ClassLoader access
        ClassLoader getClassLoader0() { return classLoader; }
    
        // Initialized in JVM not by private constructor
        // This field is filtered from reflection access, i.e. getDeclaredField
        // will throw NoSuchFieldException
        private final ClassLoader classLoader;
    
        /**
         * Returns an array of {@code TypeVariable} objects that represent the
         * type variables declared by the generic declaration represented by this
         * {@code GenericDeclaration} object, in declaration order.  Returns an
         * array of length 0 if the underlying generic declaration declares no type
         * variables.
         *
         * @return an array of {@code TypeVariable} objects that represent
         *     the type variables declared by this generic declaration
         * @throws java.lang.reflect.GenericSignatureFormatError if the generic
         *     signature of this generic declaration does not conform to
         *     the format specified in
         *     <cite>The Java&trade; Virtual Machine Specification</cite>
         * @since 1.5
         */
        @SuppressWarnings("unchecked")
        public TypeVariable<Class<T>>[] getTypeParameters() {
            ClassRepository info = getGenericInfo();
            if (info != null)
                return (TypeVariable<Class<T>>[])info.getTypeParameters();
            else
                return (TypeVariable<Class<T>>[])new TypeVariable<?>[0];
        }
    
    
        /**
         * Returns the {@code Class} representing the superclass of the entity
         * (class, interface, primitive type or void) represented by this
         * {@code Class}.  If this {@code Class} represents either the
         * {@code Object} class, an interface, a primitive type, or void, then
         * null is returned.  If this object represents an array class then the
         * {@code Class} object representing the {@code Object} class is
         * returned.
         *
         * @return the superclass of the class represented by this object.
         */
        public native Class<? super T> getSuperclass();
    
    
        /**
         * Returns the {@code Type} representing the direct superclass of
         * the entity (class, interface, primitive type or void) represented by
         * this {@code Class}.
         *
         * <p>If the superclass is a parameterized type, the {@code Type}
         * object returned must accurately reflect the actual type
         * parameters used in the source code. The parameterized type
         * representing the superclass is created if it had not been
         * created before. See the declaration of {@link
         * java.lang.reflect.ParameterizedType ParameterizedType} for the
         * semantics of the creation process for parameterized types.  If
         * this {@code Class} represents either the {@code Object}
         * class, an interface, a primitive type, or void, then null is
         * returned.  If this object represents an array class then the
         * {@code Class} object representing the {@code Object} class is
         * returned.
         *
         * @throws java.lang.reflect.GenericSignatureFormatError if the generic
         *     class signature does not conform to the format specified in
         *     <cite>The Java&trade; Virtual Machine Specification</cite>
         * @throws TypeNotPresentException if the generic superclass
         *     refers to a non-existent type declaration
         * @throws java.lang.reflect.MalformedParameterizedTypeException if the
         *     generic superclass refers to a parameterized type that cannot be
         *     instantiated  for any reason
         * @return the superclass of the class represented by this object
         * @since 1.5
         */
        public Type getGenericSuperclass() {
            ClassRepository info = getGenericInfo();
            if (info == null) {
                return getSuperclass();
            }
    
            // Historical irregularity:
            // Generic signature marks interfaces with superclass = Object
            // but this API returns null for interfaces
            if (isInterface()) {
                return null;
            }
    
            return info.getSuperclass();
        }
    
        /**
         * Gets the package for this class.  The class loader of this class is used
         * to find the package.  If the class was loaded by the bootstrap class
         * loader the set of packages loaded from CLASSPATH is searched to find the
         * package of the class. Null is returned if no package object was created
         * by the class loader of this class.
         *
         * <p> Packages have attributes for versions and specifications only if the
         * information was defined in the manifests that accompany the classes, and
         * if the class loader created the package instance with the attributes
         * from the manifest.
         *
         * @return the package of the class, or null if no package
         *         information is available from the archive or codebase.
         */
        public Package getPackage() {
            return Package.getPackage(this);
        }
    
    
        /**
         * Determines the interfaces implemented by the class or interface
         * represented by this object.
         *
         * <p> If this object represents a class, the return value is an array
         * containing objects representing all interfaces implemented by the
         * class. The order of the interface objects in the array corresponds to
         * the order of the interface names in the {@code implements} clause
         * of the declaration of the class represented by this object. For
         * example, given the declaration:
         * <blockquote>
         * {@code class Shimmer implements FloorWax, DessertTopping { ... }}
         * </blockquote>
         * suppose the value of {@code s} is an instance of
         * {@code Shimmer}; the value of the expression:
         * <blockquote>
         * {@code s.getClass().getInterfaces()[0]}
         * </blockquote>
         * is the {@code Class} object that represents interface
         * {@code FloorWax}; and the value of:
         * <blockquote>
         * {@code s.getClass().getInterfaces()[1]}
         * </blockquote>
         * is the {@code Class} object that represents interface
         * {@code DessertTopping}.
         *
         * <p> If this object represents an interface, the array contains objects
         * representing all interfaces extended by the interface. The order of the
         * interface objects in the array corresponds to the order of the interface
         * names in the {@code extends} clause of the declaration of the
         * interface represented by this object.
         *
         * <p> If this object represents a class or interface that implements no
         * interfaces, the method returns an array of length 0.
         *
         * <p> If this object represents a primitive type or void, the method
         * returns an array of length 0.
         *
         * <p> If this {@code Class} object represents an array type, the
         * interfaces {@code Cloneable} and {@code java.io.Serializable} are
         * returned in that order.
         *
         * @return an array of interfaces implemented by this class.
         */
        public Class<?>[] getInterfaces() {
            ReflectionData<T> rd = reflectionData();
            if (rd == null) {
                // no cloning required
                return getInterfaces0();
            } else {
                Class<?>[] interfaces = rd.interfaces;
                if (interfaces == null) {
                    interfaces = getInterfaces0();
                    rd.interfaces = interfaces;
                }
                // defensively copy before handing over to user code
                return interfaces.clone();
            }
        }
    
        private native Class<?>[] getInterfaces0();
    
        /**
         * Returns the {@code Type}s representing the interfaces
         * directly implemented by the class or interface represented by
         * this object.
         *
         * <p>If a superinterface is a parameterized type, the
         * {@code Type} object returned for it must accurately reflect
         * the actual type parameters used in the source code. The
         * parameterized type representing each superinterface is created
         * if it had not been created before. See the declaration of
         * {@link java.lang.reflect.ParameterizedType ParameterizedType}
         * for the semantics of the creation process for parameterized
         * types.
         *
         * <p> If this object represents a class, the return value is an
         * array containing objects representing all interfaces
         * implemented by the class. The order of the interface objects in
         * the array corresponds to the order of the interface names in
         * the {@code implements} clause of the declaration of the class
         * represented by this object.  In the case of an array class, the
         * interfaces {@code Cloneable} and {@code Serializable} are
         * returned in that order.
         *
         * <p>If this object represents an interface, the array contains
         * objects representing all interfaces directly extended by the
         * interface.  The order of the interface objects in the array
         * corresponds to the order of the interface names in the
         * {@code extends} clause of the declaration of the interface
         * represented by this object.
         *
         * <p>If this object represents a class or interface that
         * implements no interfaces, the method returns an array of length
         * 0.
         *
         * <p>If this object represents a primitive type or void, the
         * method returns an array of length 0.
         *
         * @throws java.lang.reflect.GenericSignatureFormatError
         *     if the generic class signature does not conform to the format
         *     specified in
         *     <cite>The Java&trade; Virtual Machine Specification</cite>
         * @throws TypeNotPresentException if any of the generic
         *     superinterfaces refers to a non-existent type declaration
         * @throws java.lang.reflect.MalformedParameterizedTypeException
         *     if any of the generic superinterfaces refer to a parameterized
         *     type that cannot be instantiated for any reason
         * @return an array of interfaces implemented by this class
         * @since 1.5
         */
        public Type[] getGenericInterfaces() {
            ClassRepository info = getGenericInfo();
            return (info == null) ?  getInterfaces() : info.getSuperInterfaces();
        }
    
    
        /**
         * Returns the {@code Class} representing the component type of an
         * array.  If this class does not represent an array class this method
         * returns null.
         *
         * @return the {@code Class} representing the component type of this
         * class if this class is an array
         * @see     java.lang.reflect.Array
         * @since JDK1.1
         */
        public native Class<?> getComponentType();
    
    
        /**
         * Returns the Java language modifiers for this class or interface, encoded
         * in an integer. The modifiers consist of the Java Virtual Machine's
         * constants for {@code public}, {@code protected},
         * {@code private}, {@code final}, {@code static},
         * {@code abstract} and {@code interface}; they should be decoded
         * using the methods of class {@code Modifier}.
         *
         * <p> If the underlying class is an array class, then its
         * {@code public}, {@code private} and {@code protected}
         * modifiers are the same as those of its component type.  If this
         * {@code Class} represents a primitive type or void, its
         * {@code public} modifier is always {@code true}, and its
         * {@code protected} and {@code private} modifiers are always
         * {@code false}. If this object represents an array class, a
         * primitive type or void, then its {@code final} modifier is always
         * {@code true} and its interface modifier is always
         * {@code false}. The values of its other modifiers are not determined
         * by this specification.
         *
         * <p> The modifier encodings are defined in <em>The Java Virtual Machine
         * Specification</em>, table 4.1.
         *
         * @return the {@code int} representing the modifiers for this class
         * @see     java.lang.reflect.Modifier
         * @since JDK1.1
         */
        public native int getModifiers();
    
    
        /**
         * Gets the signers of this class.
         *
         * @return  the signers of this class, or null if there are no signers.  In
         *          particular, this method returns null if this object represents
         *          a primitive type or void.
         * @since   JDK1.1
         */
        public native Object[] getSigners();
    
    
        /**
         * Set the signers of this class.
         */
        native void setSigners(Object[] signers);
    
    
        /**
         * If this {@code Class} object represents a local or anonymous
         * class within a method, returns a {@link
         * java.lang.reflect.Method Method} object representing the
         * immediately enclosing method of the underlying class. Returns
         * {@code null} otherwise.
         *
         * In particular, this method returns {@code null} if the underlying
         * class is a local or anonymous class immediately enclosed by a type
         * declaration, instance initializer or static initializer.
         *
         * @return the immediately enclosing method of the underlying class, if
         *     that class is a local or anonymous class; otherwise {@code null}.
         *
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and any of the
         *         following conditions is met:
         *
         *         <ul>
         *
         *         <li> the caller's class loader is not the same as the
         *         class loader of the enclosing class and invocation of
         *         {@link SecurityManager#checkPermission
         *         s.checkPermission} method with
         *         {@code RuntimePermission("accessDeclaredMembers")}
         *         denies access to the methods within the enclosing class
         *
         *         <li> the caller's class loader is not the same as or an
         *         ancestor of the class loader for the enclosing class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of the enclosing class
         *
         *         </ul>
         * @since 1.5
         */
        @CallerSensitive
        public Method getEnclosingMethod() throws SecurityException {
            EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
    
            if (enclosingInfo == null)
                return null;
            else {
                if (!enclosingInfo.isMethod())
                    return null;
    
                MethodRepository typeInfo = MethodRepository.make(enclosingInfo.getDescriptor(),
                                                                  getFactory());
                Class<?>   returnType       = toClass(typeInfo.getReturnType());
                Type []    parameterTypes   = typeInfo.getParameterTypes();
                Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
    
                // Convert Types to Classes; returned types *should*
                // be class objects since the methodDescriptor's used
                // don't have generics information
                for(int i = 0; i < parameterClasses.length; i++)
                    parameterClasses[i] = toClass(parameterTypes[i]);
    
                // Perform access check
                Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
                enclosingCandidate.checkMemberAccess(Member.DECLARED,
                                                     Reflection.getCallerClass(), true);
                /*
                 * Loop over all declared methods; match method name,
                 * number of and type of parameters, *and* return
                 * type.  Matching return type is also necessary
                 * because of covariant returns, etc.
                 */
                for(Method m: enclosingCandidate.getDeclaredMethods()) {
                    if (m.getName().equals(enclosingInfo.getName()) ) {
                        Class<?>[] candidateParamClasses = m.getParameterTypes();
                        if (candidateParamClasses.length == parameterClasses.length) {
                            boolean matches = true;
                            for(int i = 0; i < candidateParamClasses.length; i++) {
                                if (!candidateParamClasses[i].equals(parameterClasses[i])) {
                                    matches = false;
                                    break;
                                }
                            }
    
                            if (matches) { // finally, check return type
                                if (m.getReturnType().equals(returnType) )
                                    return m;
                            }
                        }
                    }
                }
    
                throw new InternalError("Enclosing method not found");
            }
        }
    
        private native Object[] getEnclosingMethod0();
    
        private EnclosingMethodInfo getEnclosingMethodInfo() {
            Object[] enclosingInfo = getEnclosingMethod0();
            if (enclosingInfo == null)
                return null;
            else {
                return new EnclosingMethodInfo(enclosingInfo);
            }
        }
    
        private final static class EnclosingMethodInfo {
            private Class<?> enclosingClass;
            private String name;
            private String descriptor;
    
            private EnclosingMethodInfo(Object[] enclosingInfo) {
                if (enclosingInfo.length != 3)
                    throw new InternalError("Malformed enclosing method information");
                try {
                    // The array is expected to have three elements:
    
                    // the immediately enclosing class
                    enclosingClass = (Class<?>) enclosingInfo[0];
                    assert(enclosingClass != null);
    
                    // the immediately enclosing method or constructor's
                    // name (can be null).
                    name            = (String)   enclosingInfo[1];
    
                    // the immediately enclosing method or constructor's
                    // descriptor (null iff name is).
                    descriptor      = (String)   enclosingInfo[2];
                    assert((name != null && descriptor != null) || name == descriptor);
                } catch (ClassCastException cce) {
                    throw new InternalError("Invalid type in enclosing method information", cce);
                }
            }
    
            boolean isPartial() {
                return enclosingClass == null || name == null || descriptor == null;
            }
    
            boolean isConstructor() { return !isPartial() && "<init>".equals(name); }
    
            boolean isMethod() { return !isPartial() && !isConstructor() && !"<clinit>".equals(name); }
    
            Class<?> getEnclosingClass() { return enclosingClass; }
    
            String getName() { return name; }
    
            String getDescriptor() { return descriptor; }
    
        }
    
        private static Class<?> toClass(Type o) {
            if (o instanceof GenericArrayType)
                return Array.newInstance(toClass(((GenericArrayType)o).getGenericComponentType()),
                                         0)
                    .getClass();
            return (Class<?>)o;
         }
    
        /**
         * If this {@code Class} object represents a local or anonymous
         * class within a constructor, returns a {@link
         * java.lang.reflect.Constructor Constructor} object representing
         * the immediately enclosing constructor of the underlying
         * class. Returns {@code null} otherwise.  In particular, this
         * method returns {@code null} if the underlying class is a local
         * or anonymous class immediately enclosed by a type declaration,
         * instance initializer or static initializer.
         *
         * @return the immediately enclosing constructor of the underlying class, if
         *     that class is a local or anonymous class; otherwise {@code null}.
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and any of the
         *         following conditions is met:
         *
         *         <ul>
         *
         *         <li> the caller's class loader is not the same as the
         *         class loader of the enclosing class and invocation of
         *         {@link SecurityManager#checkPermission
         *         s.checkPermission} method with
         *         {@code RuntimePermission("accessDeclaredMembers")}
         *         denies access to the constructors within the enclosing class
         *
         *         <li> the caller's class loader is not the same as or an
         *         ancestor of the class loader for the enclosing class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of the enclosing class
         *
         *         </ul>
         * @since 1.5
         */
        @CallerSensitive
        public Constructor<?> getEnclosingConstructor() throws SecurityException {
            EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
    
            if (enclosingInfo == null)
                return null;
            else {
                if (!enclosingInfo.isConstructor())
                    return null;
    
                ConstructorRepository typeInfo = ConstructorRepository.make(enclosingInfo.getDescriptor(),
                                                                            getFactory());
                Type []    parameterTypes   = typeInfo.getParameterTypes();
                Class<?>[] parameterClasses = new Class<?>[parameterTypes.length];
    
                // Convert Types to Classes; returned types *should*
                // be class objects since the methodDescriptor's used
                // don't have generics information
                for(int i = 0; i < parameterClasses.length; i++)
                    parameterClasses[i] = toClass(parameterTypes[i]);
    
                // Perform access check
                Class<?> enclosingCandidate = enclosingInfo.getEnclosingClass();
                enclosingCandidate.checkMemberAccess(Member.DECLARED,
                                                     Reflection.getCallerClass(), true);
                /*
                 * Loop over all declared constructors; match number
                 * of and type of parameters.
                 */
                for(Constructor<?> c: enclosingCandidate.getDeclaredConstructors()) {
                    Class<?>[] candidateParamClasses = c.getParameterTypes();
                    if (candidateParamClasses.length == parameterClasses.length) {
                        boolean matches = true;
                        for(int i = 0; i < candidateParamClasses.length; i++) {
                            if (!candidateParamClasses[i].equals(parameterClasses[i])) {
                                matches = false;
                                break;
                            }
                        }
    
                        if (matches)
                            return c;
                    }
                }
    
                throw new InternalError("Enclosing constructor not found");
            }
        }
    
    
        /**
         * If the class or interface represented by this {@code Class} object
         * is a member of another class, returns the {@code Class} object
         * representing the class in which it was declared.  This method returns
         * null if this class or interface is not a member of any other class.  If
         * this {@code Class} object represents an array class, a primitive
         * type, or void,then this method returns null.
         *
         * @return the declaring class for this class
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and the caller's
         *         class loader is not the same as or an ancestor of the class
         *         loader for the declaring class and invocation of {@link
         *         SecurityManager#checkPackageAccess s.checkPackageAccess()}
         *         denies access to the package of the declaring class
         * @since JDK1.1
         */
        @CallerSensitive
        public Class<?> getDeclaringClass() throws SecurityException {
            final Class<?> candidate = getDeclaringClass0();
    
            if (candidate != null)
                candidate.checkPackageAccess(
                        ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
            return candidate;
        }
    
        private native Class<?> getDeclaringClass0();
    
    
        /**
         * Returns the immediately enclosing class of the underlying
         * class.  If the underlying class is a top level class this
         * method returns {@code null}.
         * @return the immediately enclosing class of the underlying class
         * @exception  SecurityException
         *             If a security manager, <i>s</i>, is present and the caller's
         *             class loader is not the same as or an ancestor of the class
         *             loader for the enclosing class and invocation of {@link
         *             SecurityManager#checkPackageAccess s.checkPackageAccess()}
         *             denies access to the package of the enclosing class
         * @since 1.5
         */
        @CallerSensitive
        public Class<?> getEnclosingClass() throws SecurityException {
            // There are five kinds of classes (or interfaces):
            // a) Top level classes
            // b) Nested classes (static member classes)
            // c) Inner classes (non-static member classes)
            // d) Local classes (named classes declared within a method)
            // e) Anonymous classes
    
    
            // JVM Spec 4.8.6: A class must have an EnclosingMethod
            // attribute if and only if it is a local class or an
            // anonymous class.
            EnclosingMethodInfo enclosingInfo = getEnclosingMethodInfo();
            Class<?> enclosingCandidate;
    
            if (enclosingInfo == null) {
                // This is a top level or a nested class or an inner class (a, b, or c)
                enclosingCandidate = getDeclaringClass();
            } else {
                Class<?> enclosingClass = enclosingInfo.getEnclosingClass();
                // This is a local class or an anonymous class (d or e)
                if (enclosingClass == this || enclosingClass == null)
                    throw new InternalError("Malformed enclosing method information");
                else
                    enclosingCandidate = enclosingClass;
            }
    
            if (enclosingCandidate != null)
                enclosingCandidate.checkPackageAccess(
                        ClassLoader.getClassLoader(Reflection.getCallerClass()), true);
            return enclosingCandidate;
        }
    
        /**
         * Returns the simple name of the underlying class as given in the
         * source code. Returns an empty string if the underlying class is
         * anonymous.
         *
         * <p>The simple name of an array is the simple name of the
         * component type with "[]" appended.  In particular the simple
         * name of an array whose component type is anonymous is "[]".
         *
         * @return the simple name of the underlying class
         * @since 1.5
         */
        public String getSimpleName() {
            if (isArray())
                return getComponentType().getSimpleName()+"[]";
    
            String simpleName = getSimpleBinaryName();
            if (simpleName == null) { // top level class
                simpleName = getName();
                return simpleName.substring(simpleName.lastIndexOf(".")+1); // strip the package name
            }
            // According to JLS3 "Binary Compatibility" (13.1) the binary
            // name of non-package classes (not top level) is the binary
            // name of the immediately enclosing class followed by a '$' followed by:
            // (for nested and inner classes): the simple name.
            // (for local classes): 1 or more digits followed by the simple name.
            // (for anonymous classes): 1 or more digits.
    
            // Since getSimpleBinaryName() will strip the binary name of
            // the immediatly enclosing class, we are now looking at a
            // string that matches the regular expression "$[0-9]*"
            // followed by a simple name (considering the simple of an
            // anonymous class to be the empty string).
    
            // Remove leading "$[0-9]*" from the name
            int length = simpleName.length();
            if (length < 1 || simpleName.charAt(0) != '$')
                throw new InternalError("Malformed class name");
            int index = 1;
            while (index < length && isAsciiDigit(simpleName.charAt(index)))
                index++;
            // Eventually, this is the empty string iff this is an anonymous class
            return simpleName.substring(index);
        }
    
        /**
         * Return an informative string for the name of this type.
         *
         * @return an informative string for the name of this type
         * @since 1.8
         */
        public String getTypeName() {
            if (isArray()) {
                try {
                    Class<?> cl = this;
                    int dimensions = 0;
                    while (cl.isArray()) {
                        dimensions++;
                        cl = cl.getComponentType();
                    }
                    StringBuilder sb = new StringBuilder();
                    sb.append(cl.getName());
                    for (int i = 0; i < dimensions; i++) {
                        sb.append("[]");
                    }
                    return sb.toString();
                } catch (Throwable e) { /*FALLTHRU*/ }
            }
            return getName();
        }
    
        /**
         * Character.isDigit answers {@code true} to some non-ascii
         * digits.  This one does not.
         */
        private static boolean isAsciiDigit(char c) {
            return '0' <= c && c <= '9';
        }
    
        /**
         * Returns the canonical name of the underlying class as
         * defined by the Java Language Specification.  Returns null if
         * the underlying class does not have a canonical name (i.e., if
         * it is a local or anonymous class or an array whose component
         * type does not have a canonical name).
         * @return the canonical name of the underlying class if it exists, and
         * {@code null} otherwise.
         * @since 1.5
         */
        public String getCanonicalName() {
            if (isArray()) {
                String canonicalName = getComponentType().getCanonicalName();
                if (canonicalName != null)
                    return canonicalName + "[]";
                else
                    return null;
            }
            if (isLocalOrAnonymousClass())
                return null;
            Class<?> enclosingClass = getEnclosingClass();
            if (enclosingClass == null) { // top level class
                return getName();
            } else {
                String enclosingName = enclosingClass.getCanonicalName();
                if (enclosingName == null)
                    return null;
                return enclosingName + "." + getSimpleName();
            }
        }
    
        /**
         * Returns {@code true} if and only if the underlying class
         * is an anonymous class.
         *
         * @return {@code true} if and only if this class is an anonymous class.
         * @since 1.5
         */
        public boolean isAnonymousClass() {
            return "".equals(getSimpleName());
        }
    
        /**
         * Returns {@code true} if and only if the underlying class
         * is a local class.
         *
         * @return {@code true} if and only if this class is a local class.
         * @since 1.5
         */
        public boolean isLocalClass() {
            return isLocalOrAnonymousClass() && !isAnonymousClass();
        }
    
        /**
         * Returns {@code true} if and only if the underlying class
         * is a member class.
         *
         * @return {@code true} if and only if this class is a member class.
         * @since 1.5
         */
        public boolean isMemberClass() {
            return getSimpleBinaryName() != null && !isLocalOrAnonymousClass();
        }
    
        /**
         * Returns the "simple binary name" of the underlying class, i.e.,
         * the binary name without the leading enclosing class name.
         * Returns {@code null} if the underlying class is a top level
         * class.
         */
        private String getSimpleBinaryName() {
            Class<?> enclosingClass = getEnclosingClass();
            if (enclosingClass == null) // top level class
                return null;
            // Otherwise, strip the enclosing class' name
            try {
                return getName().substring(enclosingClass.getName().length());
            } catch (IndexOutOfBoundsException ex) {
                throw new InternalError("Malformed class name", ex);
            }
        }
    
        /**
         * Returns {@code true} if this is a local class or an anonymous
         * class.  Returns {@code false} otherwise.
         */
        private boolean isLocalOrAnonymousClass() {
            // JVM Spec 4.8.6: A class must have an EnclosingMethod
            // attribute if and only if it is a local class or an
            // anonymous class.
            return getEnclosingMethodInfo() != null;
        }
    
        /**
         * Returns an array containing {@code Class} objects representing all
         * the public classes and interfaces that are members of the class
         * represented by this {@code Class} object.  This includes public
         * class and interface members inherited from superclasses and public class
         * and interface members declared by the class.  This method returns an
         * array of length 0 if this {@code Class} object has no public member
         * classes or interfaces.  This method also returns an array of length 0 if
         * this {@code Class} object represents a primitive type, an array
         * class, or void.
         *
         * @return the array of {@code Class} objects representing the public
         *         members of this class
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @since JDK1.1
         */
        @CallerSensitive
        public Class<?>[] getClasses() {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), false);
    
            // Privileged so this implementation can look at DECLARED classes,
            // something the caller might not have privilege to do.  The code here
            // is allowed to look at DECLARED classes because (1) it does not hand
            // out anything other than public members and (2) public member access
            // has already been ok'd by the SecurityManager.
    
            return java.security.AccessController.doPrivileged(
                new java.security.PrivilegedAction<Class<?>[]>() {
                    public Class<?>[] run() {
                        List<Class<?>> list = new ArrayList<>();
                        Class<?> currentClass = Class.this;
                        while (currentClass != null) {
                            Class<?>[] members = currentClass.getDeclaredClasses();
                            for (int i = 0; i < members.length; i++) {
                                if (Modifier.isPublic(members[i].getModifiers())) {
                                    list.add(members[i]);
                                }
                            }
                            currentClass = currentClass.getSuperclass();
                        }
                        return list.toArray(new Class<?>[0]);
                    }
                });
        }
    
    
        /**
         * Returns an array containing {@code Field} objects reflecting all
         * the accessible public fields of the class or interface represented by
         * this {@code Class} object.
         *
         * <p> If this {@code Class} object represents a class or interface with no
         * no accessible public fields, then this method returns an array of length
         * 0.
         *
         * <p> If this {@code Class} object represents a class, then this method
         * returns the public fields of the class and of all its superclasses.
         *
         * <p> If this {@code Class} object represents an interface, then this
         * method returns the fields of the interface and of all its
         * superinterfaces.
         *
         * <p> If this {@code Class} object represents an array type, a primitive
         * type, or void, then this method returns an array of length 0.
         *
         * <p> The elements in the returned array are not sorted and are not in any
         * particular order.
         *
         * @return the array of {@code Field} objects representing the
         *         public fields
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @since JDK1.1
         * @jls 8.2 Class Members
         * @jls 8.3 Field Declarations
         */
        @CallerSensitive
        public Field[] getFields() throws SecurityException {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
            return copyFields(privateGetPublicFields(null));
        }
    
    
        /**
         * Returns an array containing {@code Method} objects reflecting all the
         * public methods of the class or interface represented by this {@code
         * Class} object, including those declared by the class or interface and
         * those inherited from superclasses and superinterfaces.
         *
         * <p> If this {@code Class} object represents a type that has multiple
         * public methods with the same name and parameter types, but different
         * return types, then the returned array has a {@code Method} object for
         * each such method.
         *
         * <p> If this {@code Class} object represents a type with a class
         * initialization method {@code <clinit>}, then the returned array does
         * <em>not</em> have a corresponding {@code Method} object.
         *
         * <p> If this {@code Class} object represents an array type, then the
         * returned array has a {@code Method} object for each of the public
         * methods inherited by the array type from {@code Object}. It does not
         * contain a {@code Method} object for {@code clone()}.
         *
         * <p> If this {@code Class} object represents an interface then the
         * returned array does not contain any implicitly declared methods from
         * {@code Object}. Therefore, if no methods are explicitly declared in
         * this interface or any of its superinterfaces then the returned array
         * has length 0. (Note that a {@code Class} object which represents a class
         * always has public methods, inherited from {@code Object}.)
         *
         * <p> If this {@code Class} object represents a primitive type or void,
         * then the returned array has length 0.
         *
         * <p> Static methods declared in superinterfaces of the class or interface
         * represented by this {@code Class} object are not considered members of
         * the class or interface.
         *
         * <p> The elements in the returned array are not sorted and are not in any
         * particular order.
         *
         * @return the array of {@code Method} objects representing the
         *         public methods of this class
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @jls 8.2 Class Members
         * @jls 8.4 Method Declarations
         * @since JDK1.1
         */
        @CallerSensitive
        public Method[] getMethods() throws SecurityException {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
            return copyMethods(privateGetPublicMethods());
        }
    
    
        /**
         * Returns an array containing {@code Constructor} objects reflecting
         * all the public constructors of the class represented by this
         * {@code Class} object.  An array of length 0 is returned if the
         * class has no public constructors, or if the class is an array class, or
         * if the class reflects a primitive type or void.
         *
         * Note that while this method returns an array of {@code
         * Constructor<T>} objects (that is an array of constructors from
         * this class), the return type of this method is {@code
         * Constructor<?>[]} and <em>not</em> {@code Constructor<T>[]} as
         * might be expected.  This less informative return type is
         * necessary since after being returned from this method, the
         * array could be modified to hold {@code Constructor} objects for
         * different classes, which would violate the type guarantees of
         * {@code Constructor<T>[]}.
         *
         * @return the array of {@code Constructor} objects representing the
         *         public constructors of this class
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @since JDK1.1
         */
        @CallerSensitive
        public Constructor<?>[] getConstructors() throws SecurityException {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
            return copyConstructors(privateGetDeclaredConstructors(true));
        }
    
    
        /**
         * Returns a {@code Field} object that reflects the specified public member
         * field of the class or interface represented by this {@code Class}
         * object. The {@code name} parameter is a {@code String} specifying the
         * simple name of the desired field.
         *
         * <p> The field to be reflected is determined by the algorithm that
         * follows.  Let C be the class or interface represented by this object:
         *
         * <OL>
         * <LI> If C declares a public field with the name specified, that is the
         *      field to be reflected.</LI>
         * <LI> If no field was found in step 1 above, this algorithm is applied
         *      recursively to each direct superinterface of C. The direct
         *      superinterfaces are searched in the order they were declared.</LI>
         * <LI> If no field was found in steps 1 and 2 above, and C has a
         *      superclass S, then this algorithm is invoked recursively upon S.
         *      If C has no superclass, then a {@code NoSuchFieldException}
         *      is thrown.</LI>
         * </OL>
         *
         * <p> If this {@code Class} object represents an array type, then this
         * method does not find the {@code length} field of the array type.
         *
         * @param name the field name
         * @return the {@code Field} object of this class specified by
         *         {@code name}
         * @throws NoSuchFieldException if a field with the specified name is
         *         not found.
         * @throws NullPointerException if {@code name} is {@code null}
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @since JDK1.1
         * @jls 8.2 Class Members
         * @jls 8.3 Field Declarations
         */
        @CallerSensitive
        public Field getField(String name)
            throws NoSuchFieldException, SecurityException {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
            Field field = getField0(name);
            if (field == null) {
                throw new NoSuchFieldException(name);
            }
            return field;
        }
    
    
        /**
         * Returns a {@code Method} object that reflects the specified public
         * member method of the class or interface represented by this
         * {@code Class} object. The {@code name} parameter is a
         * {@code String} specifying the simple name of the desired method. The
         * {@code parameterTypes} parameter is an array of {@code Class}
         * objects that identify the method's formal parameter types, in declared
         * order. If {@code parameterTypes} is {@code null}, it is
         * treated as if it were an empty array.
         *
         * <p> If the {@code name} is "{@code <init>}" or "{@code <clinit>}" a
         * {@code NoSuchMethodException} is raised. Otherwise, the method to
         * be reflected is determined by the algorithm that follows.  Let C be the
         * class or interface represented by this object:
         * <OL>
         * <LI> C is searched for a <I>matching method</I>, as defined below. If a
         *      matching method is found, it is reflected.</LI>
         * <LI> If no matching method is found by step 1 then:
         *   <OL TYPE="a">
         *   <LI> If C is a class other than {@code Object}, then this algorithm is
         *        invoked recursively on the superclass of C.</LI>
         *   <LI> If C is the class {@code Object}, or if C is an interface, then
         *        the superinterfaces of C (if any) are searched for a matching
         *        method. If any such method is found, it is reflected.</LI>
         *   </OL></LI>
         * </OL>
         *
         * <p> To find a matching method in a class or interface C:&nbsp; If C
         * declares exactly one public method with the specified name and exactly
         * the same formal parameter types, that is the method reflected. If more
         * than one such method is found in C, and one of these methods has a
         * return type that is more specific than any of the others, that method is
         * reflected; otherwise one of the methods is chosen arbitrarily.
         *
         * <p>Note that there may be more than one matching method in a
         * class because while the Java language forbids a class to
         * declare multiple methods with the same signature but different
         * return types, the Java virtual machine does not.  This
         * increased flexibility in the virtual machine can be used to
         * implement various language features.  For example, covariant
         * returns can be implemented with {@linkplain
         * java.lang.reflect.Method#isBridge bridge methods}; the bridge
         * method and the method being overridden would have the same
         * signature but different return types.
         *
         * <p> If this {@code Class} object represents an array type, then this
         * method does not find the {@code clone()} method.
         *
         * <p> Static methods declared in superinterfaces of the class or interface
         * represented by this {@code Class} object are not considered members of
         * the class or interface.
         *
         * @param name the name of the method
         * @param parameterTypes the list of parameters
         * @return the {@code Method} object that matches the specified
         *         {@code name} and {@code parameterTypes}
         * @throws NoSuchMethodException if a matching method is not found
         *         or if the name is "&lt;init&gt;"or "&lt;clinit&gt;".
         * @throws NullPointerException if {@code name} is {@code null}
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @jls 8.2 Class Members
         * @jls 8.4 Method Declarations
         * @since JDK1.1
         */
        @CallerSensitive
        public Method getMethod(String name, Class<?>... parameterTypes)
            throws NoSuchMethodException, SecurityException {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
            Method method = getMethod0(name, parameterTypes, true);
            if (method == null) {
                throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
            }
            return method;
        }
    
    
        /**
         * Returns a {@code Constructor} object that reflects the specified
         * public constructor of the class represented by this {@code Class}
         * object. The {@code parameterTypes} parameter is an array of
         * {@code Class} objects that identify the constructor's formal
         * parameter types, in declared order.
         *
         * If this {@code Class} object represents an inner class
         * declared in a non-static context, the formal parameter types
         * include the explicit enclosing instance as the first parameter.
         *
         * <p> The constructor to reflect is the public constructor of the class
         * represented by this {@code Class} object whose formal parameter
         * types match those specified by {@code parameterTypes}.
         *
         * @param parameterTypes the parameter array
         * @return the {@code Constructor} object of the public constructor that
         *         matches the specified {@code parameterTypes}
         * @throws NoSuchMethodException if a matching method is not found.
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and
         *         the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class.
         *
         * @since JDK1.1
         */
        @CallerSensitive
        public Constructor<T> getConstructor(Class<?>... parameterTypes)
            throws NoSuchMethodException, SecurityException {
            checkMemberAccess(Member.PUBLIC, Reflection.getCallerClass(), true);
            return getConstructor0(parameterTypes, Member.PUBLIC);
        }
    
    
        /**
         * Returns an array of {@code Class} objects reflecting all the
         * classes and interfaces declared as members of the class represented by
         * this {@code Class} object. This includes public, protected, default
         * (package) access, and private classes and interfaces declared by the
         * class, but excludes inherited classes and interfaces.  This method
         * returns an array of length 0 if the class declares no classes or
         * interfaces as members, or if this {@code Class} object represents a
         * primitive type, an array class, or void.
         *
         * @return the array of {@code Class} objects representing all the
         *         declared members of this class
         * @throws SecurityException
         *         If a security manager, <i>s</i>, is present and any of the
         *         following conditions is met:
         *
         *         <ul>
         *
         *         <li> the caller's class loader is not the same as the
         *         class loader of this class and invocation of
         *         {@link SecurityManager#checkPermission
         *         s.checkPermission} method with
         *         {@code RuntimePermission("accessDeclaredMembers")}
         *         denies access to the declared classes within this class
         *
         *         <li> the caller's class loader is not the same as or an
         *         ancestor of the class loader for the current class and
         *         invocation of {@link SecurityManager#checkPackageAccess
         *         s.checkPackageAccess()} denies access to the package
         *         of this class
         *
         *         </ul>
         *
         * @since JDK1.1
         */
        @CallerSensitive
        public Class<?>[] getDeclaredClasses() throws SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), false);
            return getDeclaredClasses0();
        }
    
    
        /**
         * Returns an array of {@code Field} objects reflecting all the fields
         * declared by the class or interface represented by this
         * {@code Class} object. This includes public, protected, default
         * (package) access, and private fields, but excludes inherited fields.
         *
         * <p> If this {@code Class} object represents a class or interface with no
         * declared fields, then this method returns an array of length 0.
         *
         * <p> If this {@code Class} object represents an array type, a primitive
         * type, or void, then this method returns an array of length 0.
         *
         * <p> The elements in the returned array are not sorted and are not in any
         * particular order.
         *
         * @return  the array of {@code Field} objects representing all the
         *          declared fields of this class
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and any of the
         *          following conditions is met:
         *
         *          <ul>
         *
         *          <li> the caller's class loader is not the same as the
         *          class loader of this class and invocation of
         *          {@link SecurityManager#checkPermission
         *          s.checkPermission} method with
         *          {@code RuntimePermission("accessDeclaredMembers")}
         *          denies access to the declared fields within this class
         *
         *          <li> the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class
         *
         *          </ul>
         *
         * @since JDK1.1
         * @jls 8.2 Class Members
         * @jls 8.3 Field Declarations
         */
        @CallerSensitive
        public Field[] getDeclaredFields() throws SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
            return copyFields(privateGetDeclaredFields(false));
        }
    
    
        /**
         *
         * Returns an array containing {@code Method} objects reflecting all the
         * declared methods of the class or interface represented by this {@code
         * Class} object, including public, protected, default (package)
         * access, and private methods, but excluding inherited methods.
         *
         * <p> If this {@code Class} object represents a type that has multiple
         * declared methods with the same name and parameter types, but different
         * return types, then the returned array has a {@code Method} object for
         * each such method.
         *
         * <p> If this {@code Class} object represents a type that has a class
         * initialization method {@code <clinit>}, then the returned array does
         * <em>not</em> have a corresponding {@code Method} object.
         *
         * <p> If this {@code Class} object represents a class or interface with no
         * declared methods, then the returned array has length 0.
         *
         * <p> If this {@code Class} object represents an array type, a primitive
         * type, or void, then the returned array has length 0.
         *
         * <p> The elements in the returned array are not sorted and are not in any
         * particular order.
         *
         * @return  the array of {@code Method} objects representing all the
         *          declared methods of this class
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and any of the
         *          following conditions is met:
         *
         *          <ul>
         *
         *          <li> the caller's class loader is not the same as the
         *          class loader of this class and invocation of
         *          {@link SecurityManager#checkPermission
         *          s.checkPermission} method with
         *          {@code RuntimePermission("accessDeclaredMembers")}
         *          denies access to the declared methods within this class
         *
         *          <li> the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class
         *
         *          </ul>
         *
         * @jls 8.2 Class Members
         * @jls 8.4 Method Declarations
         * @since JDK1.1
         */
        @CallerSensitive
        public Method[] getDeclaredMethods() throws SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
            return copyMethods(privateGetDeclaredMethods(false));
        }
    
    
        /**
         * Returns an array of {@code Constructor} objects reflecting all the
         * constructors declared by the class represented by this
         * {@code Class} object. These are public, protected, default
         * (package) access, and private constructors.  The elements in the array
         * returned are not sorted and are not in any particular order.  If the
         * class has a default constructor, it is included in the returned array.
         * This method returns an array of length 0 if this {@code Class}
         * object represents an interface, a primitive type, an array class, or
         * void.
         *
         * <p> See <em>The Java Language Specification</em>, section 8.2.
         *
         * @return  the array of {@code Constructor} objects representing all the
         *          declared constructors of this class
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and any of the
         *          following conditions is met:
         *
         *          <ul>
         *
         *          <li> the caller's class loader is not the same as the
         *          class loader of this class and invocation of
         *          {@link SecurityManager#checkPermission
         *          s.checkPermission} method with
         *          {@code RuntimePermission("accessDeclaredMembers")}
         *          denies access to the declared constructors within this class
         *
         *          <li> the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class
         *
         *          </ul>
         *
         * @since JDK1.1
         */
        @CallerSensitive
        public Constructor<?>[] getDeclaredConstructors() throws SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
            return copyConstructors(privateGetDeclaredConstructors(false));
        }
    
    
        /**
         * Returns a {@code Field} object that reflects the specified declared
         * field of the class or interface represented by this {@code Class}
         * object. The {@code name} parameter is a {@code String} that specifies
         * the simple name of the desired field.
         *
         * <p> If this {@code Class} object represents an array type, then this
         * method does not find the {@code length} field of the array type.
         *
         * @param name the name of the field
         * @return  the {@code Field} object for the specified field in this
         *          class
         * @throws  NoSuchFieldException if a field with the specified name is
         *          not found.
         * @throws  NullPointerException if {@code name} is {@code null}
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and any of the
         *          following conditions is met:
         *
         *          <ul>
         *
         *          <li> the caller's class loader is not the same as the
         *          class loader of this class and invocation of
         *          {@link SecurityManager#checkPermission
         *          s.checkPermission} method with
         *          {@code RuntimePermission("accessDeclaredMembers")}
         *          denies access to the declared field
         *
         *          <li> the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class
         *
         *          </ul>
         *
         * @since JDK1.1
         * @jls 8.2 Class Members
         * @jls 8.3 Field Declarations
         */
        @CallerSensitive
        public Field getDeclaredField(String name)
            throws NoSuchFieldException, SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
            Field field = searchFields(privateGetDeclaredFields(false), name);
            if (field == null) {
                throw new NoSuchFieldException(name);
            }
            return field;
        }
    
    
        /**
         * Returns a {@code Method} object that reflects the specified
         * declared method of the class or interface represented by this
         * {@code Class} object. The {@code name} parameter is a
         * {@code String} that specifies the simple name of the desired
         * method, and the {@code parameterTypes} parameter is an array of
         * {@code Class} objects that identify the method's formal parameter
         * types, in declared order.  If more than one method with the same
         * parameter types is declared in a class, and one of these methods has a
         * return type that is more specific than any of the others, that method is
         * returned; otherwise one of the methods is chosen arbitrarily.  If the
         * name is "&lt;init&gt;"or "&lt;clinit&gt;" a {@code NoSuchMethodException}
         * is raised.
         *
         * <p> If this {@code Class} object represents an array type, then this
         * method does not find the {@code clone()} method.
         *
         * @param name the name of the method
         * @param parameterTypes the parameter array
         * @return  the {@code Method} object for the method of this class
         *          matching the specified name and parameters
         * @throws  NoSuchMethodException if a matching method is not found.
         * @throws  NullPointerException if {@code name} is {@code null}
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and any of the
         *          following conditions is met:
         *
         *          <ul>
         *
         *          <li> the caller's class loader is not the same as the
         *          class loader of this class and invocation of
         *          {@link SecurityManager#checkPermission
         *          s.checkPermission} method with
         *          {@code RuntimePermission("accessDeclaredMembers")}
         *          denies access to the declared method
         *
         *          <li> the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class
         *
         *          </ul>
         *
         * @jls 8.2 Class Members
         * @jls 8.4 Method Declarations
         * @since JDK1.1
         */
        @CallerSensitive
        public Method getDeclaredMethod(String name, Class<?>... parameterTypes)
            throws NoSuchMethodException, SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
            Method method = searchMethods(privateGetDeclaredMethods(false), name, parameterTypes);
            if (method == null) {
                throw new NoSuchMethodException(getName() + "." + name + argumentTypesToString(parameterTypes));
            }
            return method;
        }
    
    
        /**
         * Returns a {@code Constructor} object that reflects the specified
         * constructor of the class or interface represented by this
         * {@code Class} object.  The {@code parameterTypes} parameter is
         * an array of {@code Class} objects that identify the constructor's
         * formal parameter types, in declared order.
         *
         * If this {@code Class} object represents an inner class
         * declared in a non-static context, the formal parameter types
         * include the explicit enclosing instance as the first parameter.
         *
         * @param parameterTypes the parameter array
         * @return  The {@code Constructor} object for the constructor with the
         *          specified parameter list
         * @throws  NoSuchMethodException if a matching method is not found.
         * @throws  SecurityException
         *          If a security manager, <i>s</i>, is present and any of the
         *          following conditions is met:
         *
         *          <ul>
         *
         *          <li> the caller's class loader is not the same as the
         *          class loader of this class and invocation of
         *          {@link SecurityManager#checkPermission
         *          s.checkPermission} method with
         *          {@code RuntimePermission("accessDeclaredMembers")}
         *          denies access to the declared constructor
         *
         *          <li> the caller's class loader is not the same as or an
         *          ancestor of the class loader for the current class and
         *          invocation of {@link SecurityManager#checkPackageAccess
         *          s.checkPackageAccess()} denies access to the package
         *          of this class
         *
         *          </ul>
         *
         * @since JDK1.1
         */
        @CallerSensitive
        public Constructor<T> getDeclaredConstructor(Class<?>... parameterTypes)
            throws NoSuchMethodException, SecurityException {
            checkMemberAccess(Member.DECLARED, Reflection.getCallerClass(), true);
            return getConstructor0(parameterTypes, Member.DECLARED);
        }
    
        /**
         * Finds a resource with a given name.  The rules for searching resources
         * associated with a given class are implemented by the defining
         * {@linkplain ClassLoader class loader} of the class.  This method
         * delegates to this object's class loader.  If this object was loaded by
         * the bootstrap class loader, the method delegates to {@link
         * ClassLoader#getSystemResourceAsStream}.
         *
         * <p> Before delegation, an absolute resource name is constructed from the
         * given resource name using this algorithm:
         *
         * <ul>
         *
         * <li> If the {@code name} begins with a {@code '/'}
         * (<tt>'&#92;u002f'</tt>), then the absolute name of the resource is the
         * portion of the {@code name} following the {@code '/'}.
         *
         * <li> Otherwise, the absolute name is of the following form:
         *
         * <blockquote>
         *   {@code modified_package_name/name}
         * </blockquote>
         *
         * <p> Where the {@code modified_package_name} is the package name of this
         * object with {@code '/'} substituted for {@code '.'}
         * (<tt>'&#92;u002e'</tt>).
         *
         * </ul>
         *
         * @param  name name of the desired resource
         * @return      A {@link java.io.InputStream} object or {@code null} if
         *              no resource with this name is found
         * @throws  NullPointerException If {@code name} is {@code null}
         * @since  JDK1.1
         */
         public InputStream getResourceAsStream(String name) {
            name = resolveName(name);
            ClassLoader cl = getClassLoader0();
            if (cl==null) {
                // A system class.
                return ClassLoader.getSystemResourceAsStream(name);
            }
            return cl.getResourceAsStream(name);
        }
    
        /**
         * Finds a resource with a given name.  The rules for searching resources
         * associated with a given class are implemented by the defining
         * {@linkplain ClassLoader class loader} of the class.  This method
         * delegates to this object's class loader.  If this object was loaded by
         * the bootstrap class loader, the method delegates to {@link
         * ClassLoader#getSystemResource}.
         *
         * <p> Before delegation, an absolute resource name is constructed from the
         * given resource name using this algorithm:
         *
         * <ul>
         *
         * <li> If the {@code name} begins with a {@code '/'}
         * (<tt>'&#92;u002f'</tt>), then the absolute name of the resource is the
         * portion of the {@code name} following the {@code '/'}.
         *
         * <li> Otherwise, the absolute name is of the following form:
         *
         * <blockquote>
         *   {@code modified_package_name/name}
         * </blockquote>
         *
         * <p> Where the {@code modified_package_name} is the package name of this
         * object with {@code '/'} substituted for {@code '.'}
         * (<tt>'&#92;u002e'</tt>).
         *
         * </ul>
         *
         * @param  name name of the desired resource
         * @return      A  {@link java.net.URL} object or {@code null} if no
         *              resource with this name is found
         * @since  JDK1.1
         */
        public java.net.URL getResource(String name) {
            name = resolveName(name);
            ClassLoader cl = getClassLoader0();
            if (cl==null) {
                // A system class.
                return ClassLoader.getSystemResource(name);
            }
            return cl.getResource(name);
        }
    
    
    
        /** protection domain returned when the internal domain is null */
        private static java.security.ProtectionDomain allPermDomain;
    
    
        /**
         * Returns the {@code ProtectionDomain} of this class.  If there is a
         * security manager installed, this method first calls the security
         * manager's {@code checkPermission} method with a
         * {@code RuntimePermission("getProtectionDomain")} permission to
         * ensure it's ok to get the
         * {@code ProtectionDomain}.
         *
         * @return the ProtectionDomain of this class
         *
         * @throws SecurityException
         *        if a security manager exists and its
         *        {@code checkPermission} method doesn't allow
         *        getting the ProtectionDomain.
         *
         * @see java.security.ProtectionDomain
         * @see SecurityManager#checkPermission
         * @see java.lang.RuntimePermission
         * @since 1.2
         */
        public java.security.ProtectionDomain getProtectionDomain() {
            SecurityManager sm = System.getSecurityManager();
            if (sm != null) {
                sm.checkPermission(SecurityConstants.GET_PD_PERMISSION);
            }
            java.security.ProtectionDomain pd = getProtectionDomain0();
            if (pd == null) {
                if (allPermDomain == null) {
                    java.security.Permissions perms =
                        new java.security.Permissions();
                    perms.add(SecurityConstants.ALL_PERMISSION);
                    allPermDomain =
                        new java.security.ProtectionDomain(null, perms);
                }
                pd = allPermDomain;
            }
            return pd;
        }
    
    
        /**
         * Returns the ProtectionDomain of this class.
         */
        private native java.security.ProtectionDomain getProtectionDomain0();
    
        /*
         * Return the Virtual Machine's Class object for the named
         * primitive type.
         */
        static native Class<?> getPrimitiveClass(String name);
    
        /*
         * Check if client is allowed to access members.  If access is denied,
         * throw a SecurityException.
         *
         * This method also enforces package access.
         *
         * <p> Default policy: allow all clients access with normal Java access
         * control.
         */
        private void checkMemberAccess(int which, Class<?> caller, boolean checkProxyInterfaces) {
            final SecurityManager s = System.getSecurityManager();
            if (s != null) {
                /* Default policy allows access to all {@link Member#PUBLIC} members,
                 * as well as access to classes that have the same class loader as the caller.
                 * In all other cases, it requires RuntimePermission("accessDeclaredMembers")
                 * permission.
                 */
                final ClassLoader ccl = ClassLoader.getClassLoader(caller);
                final ClassLoader cl = getClassLoader0();
                if (which != Member.PUBLIC) {
                    if (ccl != cl) {
                        s.checkPermission(SecurityConstants.CHECK_MEMBER_ACCESS_PERMISSION);
                    }
                }
                this.checkPackageAccess(ccl, checkProxyInterfaces);
            }
        }
    
        /*
         * Checks if a client loaded in ClassLoader ccl is allowed to access this
         * class under the current package access policy. If access is denied,
         * throw a SecurityException.
         */
        private void checkPackageAccess(final ClassLoader ccl, boolean checkProxyInterfaces) {
            final SecurityManager s = System.getSecurityManager();
            if (s != null) {
                final ClassLoader cl = getClassLoader0();
    
                if (ReflectUtil.needsPackageAccessCheck(ccl, cl)) {
                    String name = this.getName();
                    int i = name.lastIndexOf('.');
                    if (i != -1) {
                        // skip the package access check on a proxy class in default proxy package
                        String pkg = name.substring(0, i);
                        if (!Proxy.isProxyClass(this) || ReflectUtil.isNonPublicProxyClass(this)) {
                            s.checkPackageAccess(pkg);
                        }
                    }
                }
                // check package access on the proxy interfaces
                if (checkProxyInterfaces && Proxy.isProxyClass(this)) {
                    ReflectUtil.checkProxyPackageAccess(ccl, this.getInterfaces());
                }
            }
        }
    
        /**
         * Add a package name prefix if the name is not absolute Remove leading "/"
         * if name is absolute
         */
        private String resolveName(String name) {
            if (name == null) {
                return name;
            }
            if (!name.startsWith("/")) {
                Class<?> c = this;
                while (c.isArray()) {
                    c = c.getComponentType();
                }
                String baseName = c.getName();
                int index = baseName.lastIndexOf('.');
                if (index != -1) {
                    name = baseName.substring(0, index).replace('.', '/')
                        +"/"+name;
                }
            } else {
                name = name.substring(1);
            }
            return name;
        }
    
        /**
         * Atomic operations support.
         */
        private static class Atomic {
            // initialize Unsafe machinery here, since we need to call Class.class instance method
            // and have to avoid calling it in the static initializer of the Class class...
            private static final Unsafe unsafe = Unsafe.getUnsafe();
            // offset of Class.reflectionData instance field
            private static final long reflectionDataOffset;
            // offset of Class.annotationType instance field
            private static final long annotationTypeOffset;
            // offset of Class.annotationData instance field
            private static final long annotationDataOffset;
    
            static {
                Field[] fields = Class.class.getDeclaredFields0(false); // bypass caches
                reflectionDataOffset = objectFieldOffset(fields, "reflectionData");
                annotationTypeOffset = objectFieldOffset(fields, "annotationType");
                annotationDataOffset = objectFieldOffset(fields, "annotationData");
            }
    
            private static long objectFieldOffset(Field[] fields, String fieldName) {
                Field field = searchFields(fields, fieldName);
                if (field == null) {
                    throw new Error("No " + fieldName + " field found in java.lang.Class");
                }
                return unsafe.objectFieldOffset(field);
            }
    
            static <T> boolean casReflectionData(Class<?> clazz,
                                                 SoftReference<ReflectionData<T>> oldData,
                                                 SoftReference<ReflectionData<T>> newData) {
                return unsafe.compareAndSwapObject(clazz, reflectionDataOffset, oldData, newData);
            }
    
            static <T> boolean casAnnotationType(Class<?> clazz,
                                                 AnnotationType oldType,
                                                 AnnotationType newType) {
                return unsafe.compareAndSwapObject(clazz, annotationTypeOffset, oldType, newType);
            }
    
            static <T> boolean casAnnotationData(Class<?> clazz,
                                                 AnnotationData oldData,
                                                 AnnotationData newData) {
                return unsafe.compareAndSwapObject(clazz, annotationDataOffset, oldData, newData);
            }
        }
    
        /**
         * Reflection support.
         */
    
        // Caches for certain reflective results
        private static boolean useCaches = true;
    
        // reflection data that might get invalidated when JVM TI RedefineClasses() is called
        private static class ReflectionData<T> {
            volatile Field[] declaredFields;
            volatile Field[] publicFields;
            volatile Method[] declaredMethods;
            volatile Method[] publicMethods;
            volatile Constructor<T>[] declaredConstructors;
            volatile Constructor<T>[] publicConstructors;
            // Intermediate results for getFields and getMethods
            volatile Field[] declaredPublicFields;
            volatile Method[] declaredPublicMethods;
            volatile Class<?>[] interfaces;
    
            // Value of classRedefinedCount when we created this ReflectionData instance
            final int redefinedCount;
    
            ReflectionData(int redefinedCount) {
                this.redefinedCount = redefinedCount;
            }
        }
    
        private volatile transient SoftReference<ReflectionData<T>> reflectionData;
    
        // Incremented by the VM on each call to JVM TI RedefineClasses()
        // that redefines this class or a superclass.
        private volatile transient int classRedefinedCount = 0;
    
        // Lazily create and cache ReflectionData
        private ReflectionData<T> reflectionData() {
            SoftReference<ReflectionData<T>> reflectionData = this.reflectionData;
            int classRedefinedCount = this.classRedefinedCount;
            ReflectionData<T> rd;
            if (useCaches &&
                reflectionData != null &&
                (rd = reflectionData.get()) != null &&
                rd.redefinedCount == classRedefinedCount) {
                return rd;
            }
            // else no SoftReference or cleared SoftReference or stale ReflectionData
            // -> create and replace new instance
            return newReflectionData(reflectionData, classRedefinedCount);
        }
    
        private ReflectionData<T> newReflectionData(SoftReference<ReflectionData<T>> oldReflectionData,
                                                    int classRedefinedCount) {
            if (!useCaches) return null;
    
            while (true) {
                ReflectionData<T> rd = new ReflectionData<>(classRedefinedCount);
                // try to CAS it...
                if (Atomic.casReflectionData(this, oldReflectionData, new SoftReference<>(rd))) {
                    return rd;
                }
                // else retry
                oldReflectionData = this.reflectionData;
                classRedefinedCount = this.classRedefinedCount;
                if (oldReflectionData != null &&
                    (rd = oldReflectionData.get()) != null &&
                    rd.redefinedCount == classRedefinedCount) {
                    return rd;
                }
            }
        }
    
        // Generic signature handling
        private native String getGenericSignature0();
    
        // Generic info repository; lazily initialized
        private volatile transient ClassRepository genericInfo;
    
        // accessor for factory
        private GenericsFactory getFactory() {
            // create scope and factory
            return CoreReflectionFactory.make(this, ClassScope.make(this));
        }
    
        // accessor for generic info repository;
        // generic info is lazily initialized
        private ClassRepository getGenericInfo() {
            ClassRepository genericInfo = this.genericInfo;
            if (genericInfo == null) {
                String signature = getGenericSignature0();
                if (signature == null) {
                    genericInfo = ClassRepository.NONE;
                } else {
                    genericInfo = ClassRepository.make(signature, getFactory());
                }
                this.genericInfo = genericInfo;
            }
            return (genericInfo != ClassRepository.NONE) ? genericInfo : null;
        }
    
        // Annotations handling
        native byte[] getRawAnnotations();
        // Since 1.8
        native byte[] getRawTypeAnnotations();
        static byte[] getExecutableTypeAnnotationBytes(Executable ex) {
            return getReflectionFactory().getExecutableTypeAnnotationBytes(ex);
        }
    
        native ConstantPool getConstantPool();
    
        //
        //
        // java.lang.reflect.Field handling
        //
        //
    
        // Returns an array of "root" fields. These Field objects must NOT
        // be propagated to the outside world, but must instead be copied
        // via ReflectionFactory.copyField.
        private Field[] privateGetDeclaredFields(boolean publicOnly) {
            checkInitted();
            Field[] res;
            ReflectionData<T> rd = reflectionData();
            if (rd != null) {
                res = publicOnly ? rd.declaredPublicFields : rd.declaredFields;
                if (res != null) return res;
            }
            // No cached value available; request value from VM
            res = Reflection.filterFields(this, getDeclaredFields0(publicOnly));
            if (rd != null) {
                if (publicOnly) {
                    rd.declaredPublicFields = res;
                } else {
                    rd.declaredFields = res;
                }
            }
            return res;
        }
    
        // Returns an array of "root" fields. These Field objects must NOT
        // be propagated to the outside world, but must instead be copied
        // via ReflectionFactory.copyField.
        private Field[] privateGetPublicFields(Set<Class<?>> traversedInterfaces) {
            checkInitted();
            Field[] res;
            ReflectionData<T> rd = reflectionData();
            if (rd != null) {
                res = rd.publicFields;
                if (res != null) return res;
            }
    
            // No cached value available; compute value recursively.
            // Traverse in correct order for getField().
            List<Field> fields = new ArrayList<>();
            if (traversedInterfaces == null) {
                traversedInterfaces = new HashSet<>();
            }
    
            // Local fields
            Field[] tmp = privateGetDeclaredFields(true);
            addAll(fields, tmp);
    
            // Direct superinterfaces, recursively
            for (Class<?> c : getInterfaces()) {
                if (!traversedInterfaces.contains(c)) {
                    traversedInterfaces.add(c);
                    addAll(fields, c.privateGetPublicFields(traversedInterfaces));
                }
            }
    
            // Direct superclass, recursively
            if (!isInterface()) {
                Class<?> c = getSuperclass();
                if (c != null) {
                    addAll(fields, c.privateGetPublicFields(traversedInterfaces));
                }
            }
    
            res = new Field[fields.size()];
            fields.toArray(res);
            if (rd != null) {
                rd.publicFields = res;
            }
            return res;
        }
    
        private static void addAll(Collection<Field> c, Field[] o) {
            for (int i = 0; i < o.length; i++) {
                c.add(o[i]);
            }
        }
    
    
        //
        //
        // java.lang.reflect.Constructor handling
        //
        //
    
        // Returns an array of "root" constructors. These Constructor
        // objects must NOT be propagated to the outside world, but must
        // instead be copied via ReflectionFactory.copyConstructor.
        private Constructor<T>[] privateGetDeclaredConstructors(boolean publicOnly) {
            checkInitted();
            Constructor<T>[] res;
            ReflectionData<T> rd = reflectionData();
            if (rd != null) {
                res = publicOnly ? rd.publicConstructors : rd.declaredConstructors;
                if (res != null) return res;
            }
            // No cached value available; request value from VM
            if (isInterface()) {
                @SuppressWarnings("unchecked")
                Constructor<T>[] temporaryRes = (Constructor<T>[]) new Constructor<?>[0];
                res = temporaryRes;
            } else {
                res = getDeclaredConstructors0(publicOnly);
            }
            if (rd != null) {
                if (publicOnly) {
                    rd.publicConstructors = res;
                } else {
                    rd.declaredConstructors = res;
                }
            }
            return res;
        }
    
        //
        //
        // java.lang.reflect.Method handling
        //
        //
    
        // Returns an array of "root" methods. These Method objects must NOT
        // be propagated to the outside world, but must instead be copied
        // via ReflectionFactory.copyMethod.
        private Method[] privateGetDeclaredMethods(boolean publicOnly) {
            checkInitted();
            Method[] res;
            ReflectionData<T> rd = reflectionData();
            if (rd != null) {
                res = publicOnly ? rd.declaredPublicMethods : rd.declaredMethods;
                if (res != null) return res;
            }
            // No cached value available; request value from VM
            res = Reflection.filterMethods(this, getDeclaredMethods0(publicOnly));
            if (rd != null) {
                if (publicOnly) {
                    rd.declaredPublicMethods = res;
                } else {
                    rd.declaredMethods = res;
                }
            }
            return res;
        }
    
        static class MethodArray {
            // Don't add or remove methods except by add() or remove() calls.
            private Method[] methods;
            private int length;
            private int defaults;
    
            MethodArray() {
                this(20);
            }
    
            MethodArray(int initialSize) {
                if (initialSize < 2)
                    throw new IllegalArgumentException("Size should be 2 or more");
    
                methods = new Method[initialSize];
                length = 0;
                defaults = 0;
            }
    
            boolean hasDefaults() {
                return defaults != 0;
            }
    
            void add(Method m) {
                if (length == methods.length) {
                    methods = Arrays.copyOf(methods, 2 * methods.length);
                }
                methods[length++] = m;
    
                if (m != null && m.isDefault())
                    defaults++;
            }
    
            void addAll(Method[] ma) {
                for (int i = 0; i < ma.length; i++) {
                    add(ma[i]);
                }
            }
    
            void addAll(MethodArray ma) {
                for (int i = 0; i < ma.length(); i++) {
                    add(ma.get(i));
                }
            }
    
            void addIfNotPresent(Method newMethod) {
                for (int i = 0; i < length; i++) {
                    Method m = methods[i];
                    if (m == newMethod || (m != null && m.equals(newMethod))) {
                        return;
                    }
                }
                add(newMethod);
            }
    
            void addAllIfNotPresent(MethodArray newMethods) {
                for (int i = 0; i < newMethods.length(); i++) {
                    Method m = newMethods.get(i);
                    if (m != null) {
                        addIfNotPresent(m);
                    }
                }
            }
    
            /* Add Methods declared in an interface to this MethodArray.
             * Static methods declared in interfaces are not inherited.
             */
            void addInterfaceMethods(Method[] methods) {
                for (Method candidate : methods) {
                    if (!Modifier.isStatic(candidate.getModifiers())) {
                        add(candidate);
                    }
                }
            }
    
            int length() {
                return length;
            }
    
            Method get(int i) {
                return methods[i];
            }
    
            Method getFirst() {
                for (Method m : methods)
                    if (m != null)
                        return m;
                return null;
            }
    
            void removeByNameAndDescriptor(Method toRemove) {
                for (int i = 0; i < length; i++) {
                    Method m = methods[i];
                    if (m != null && matchesNameAndDescriptor(m, toRemove)) {
                        remove(i);
                    }
                }
            }
    
            private void remove(int i) {
                if (methods[i] != null && methods[i].isDefault())
                    defaults--;
                methods[i] = null;
            }
    
            private boolean matchesNameAndDescriptor(Method m1, Method m2) {
                return m1.getReturnType() == m2.getReturnType() &&
                       m1.getName() == m2.getName() && // name is guaranteed to be interned
                       arrayContentsEq(m1.getParameterTypes(),
                               m2.getParameterTypes());
            }
    
            void compactAndTrim() {
                int newPos = 0;
                // Get rid of null slots
                for (int pos = 0; pos < length; pos++) {
                    Method m = methods[pos];
                    if (m != null) {
                        if (pos != newPos) {
                            methods[newPos] = m;
                        }
                        newPos++;
                    }
                }
                if (newPos != methods.length) {
                    methods = Arrays.copyOf(methods, newPos);
                }
            }
    
            /* Removes all Methods from this MethodArray that have a more specific
             * default Method in this MethodArray.
             *
             * Users of MethodArray are responsible for pruning Methods that have
             * a more specific <em>concrete</em> Method.
             */
            void removeLessSpecifics() {
                if (!hasDefaults())
                    return;
    
                for (int i = 0; i < length; i++) {
                    Method m = get(i);
                    if  (m == null || !m.isDefault())
                        continue;
    
                    for (int j  = 0; j < length; j++) {
                        if (i == j)
                            continue;
    
                        Method candidate = get(j);
                        if (candidate == null)
                            continue;
    
                        if (!matchesNameAndDescriptor(m, candidate))
                            continue;
    
                        if (hasMoreSpecificClass(m, candidate))
                            remove(j);
                    }
                }
            }
    
            Method[] getArray() {
                return methods;
            }
    
            // Returns true if m1 is more specific than m2
            static boolean hasMoreSpecificClass(Method m1, Method m2) {
                Class<?> m1Class = m1.getDeclaringClass();
                Class<?> m2Class = m2.getDeclaringClass();
                return m1Class != m2Class && m2Class.isAssignableFrom(m1Class);
            }
        }
    
    
        // Returns an array of "root" methods. These Method objects must NOT
        // be propagated to the outside world, but must instead be copied
        // via ReflectionFactory.copyMethod.
        private Method[] privateGetPublicMethods() {
            checkInitted();
            Method[] res;
            ReflectionData<T> rd = reflectionData();
            if (rd != null) {
                res = rd.publicMethods;
                if (res != null) return res;
            }
    
            // No cached value available; compute value recursively.
            // Start by fetching public declared methods
            MethodArray methods = new MethodArray();
            {
                Method[] tmp = privateGetDeclaredMethods(true);
                methods.addAll(tmp);
            }
            // Now recur over superclass and direct superinterfaces.
            // Go over superinterfaces first so we can more easily filter
            // out concrete implementations inherited from superclasses at
            // the end.
            MethodArray inheritedMethods = new MethodArray();
            for (Class<?> i : getInterfaces()) {
                inheritedMethods.addInterfaceMethods(i.privateGetPublicMethods());
            }
            if (!isInterface()) {
                Class<?> c = getSuperclass();
                if (c != null) {
                    MethodArray supers = new MethodArray();
                    supers.addAll(c.privateGetPublicMethods());
                    // Filter out concrete implementations of any
                    // interface methods
                    for (int i = 0; i < supers.length(); i++) {
                        Method m = supers.get(i);
                        if (m != null &&
                                !Modifier.isAbstract(m.getModifiers()) &&
                                !m.isDefault()) {
                            inheritedMethods.removeByNameAndDescriptor(m);
                        }
                    }
                    // Insert superclass's inherited methods before
                    // superinterfaces' to satisfy getMethod's search
                    // order
                    supers.addAll(inheritedMethods);
                    inheritedMethods = supers;
                }
            }
            // Filter out all local methods from inherited ones
            for (int i = 0; i < methods.length(); i++) {
                Method m = methods.get(i);
                inheritedMethods.removeByNameAndDescriptor(m);
            }
            methods.addAllIfNotPresent(inheritedMethods);
            methods.removeLessSpecifics();
            methods.compactAndTrim();
            res = methods.getArray();
            if (rd != null) {
                rd.publicMethods = res;
            }
            return res;
        }
    
    
        //
        // Helpers for fetchers of one field, method, or constructor
        //
    
        private static Field searchFields(Field[] fields, String name) {
            String internedName = name.intern();
            for (int i = 0; i < fields.length; i++) {
                if (fields[i].getName() == internedName) {
                    return getReflectionFactory().copyField(fields[i]);
                }
            }
            return null;
        }
    
        private Field getField0(String name) throws NoSuchFieldException {
            // Note: the intent is that the search algorithm this routine
            // uses be equivalent to the ordering imposed by
            // privateGetPublicFields(). It fetches only the declared
            // public fields for each class, however, to reduce the number
            // of Field objects which have to be created for the common
            // case where the field being requested is declared in the
            // class which is being queried.
            Field res;
            // Search declared public fields
            if ((res = searchFields(privateGetDeclaredFields(true), name)) != null) {
                return res;
            }
            // Direct superinterfaces, recursively
            Class<?>[] interfaces = getInterfaces();
            for (int i = 0; i < interfaces.length; i++) {
                Class<?> c = interfaces[i];
                if ((res = c.getField0(name)) != null) {
                    return res;
                }
            }
            // Direct superclass, recursively
            if (!isInterface()) {
                Class<?> c = getSuperclass();
                if (c != null) {
                    if ((res = c.getField0(name)) != null) {
                        return res;
                    }
                }
            }
            return null;
        }
    
        private static Method searchMethods(Method[] methods,
                                            String name,
                                            Class<?>[] parameterTypes)
        {
            Method res = null;
            String internedName = name.intern();
            for (int i = 0; i < methods.length; i++) {
                Method m = methods[i];
                if (m.getName() == internedName
                    && arrayContentsEq(parameterTypes, m.getParameterTypes())
                    && (res == null
                        || res.getReturnType().isAssignableFrom(m.getReturnType())))
                    res = m;
            }
    
            return (res == null ? res : getReflectionFactory().copyMethod(res));
        }
    
        private Method getMethod0(String name, Class<?>[] parameterTypes, boolean includeStaticMethods) {
            MethodArray interfaceCandidates = new MethodArray(2);
            Method res =  privateGetMethodRecursive(name, parameterTypes, includeStaticMethods, interfaceCandidates);
            if (res != null)
                return res;
    
            // Not found on class or superclass directly
            interfaceCandidates.removeLessSpecifics();
            return interfaceCandidates.getFirst(); // may be null
        }
    
        private Method privateGetMethodRecursive(String name,
                Class<?>[] parameterTypes,
                boolean includeStaticMethods,
                MethodArray allInterfaceCandidates) {
            // Note: the intent is that the search algorithm this routine
            // uses be equivalent to the ordering imposed by
            // privateGetPublicMethods(). It fetches only the declared
            // public methods for each class, however, to reduce the
            // number of Method objects which have to be created for the
            // common case where the method being requested is declared in
            // the class which is being queried.
            //
            // Due to default methods, unless a method is found on a superclass,
            // methods declared in any superinterface needs to be considered.
            // Collect all candidates declared in superinterfaces in {@code
            // allInterfaceCandidates} and select the most specific if no match on
            // a superclass is found.
    
            // Must _not_ return root methods
            Method res;
            // Search declared public methods
            if ((res = searchMethods(privateGetDeclaredMethods(true),
                                     name,
                                     parameterTypes)) != null) {
                if (includeStaticMethods || !Modifier.isStatic(res.getModifiers()))
                    return res;
            }
            // Search superclass's methods
            if (!isInterface()) {
                Class<? super T> c = getSuperclass();
                if (c != null) {
                    if ((res = c.getMethod0(name, parameterTypes, true)) != null) {
                        return res;
                    }
                }
            }
            // Search superinterfaces' methods
            Class<?>[] interfaces = getInterfaces();
            for (Class<?> c : interfaces)
                if ((res = c.getMethod0(name, parameterTypes, false)) != null)
                    allInterfaceCandidates.add(res);
            // Not found
            return null;
        }
    
        private Constructor<T> getConstructor0(Class<?>[] parameterTypes,
                                            int which) throws NoSuchMethodException
        {
            Constructor<T>[] constructors = privateGetDeclaredConstructors((which == Member.PUBLIC));
            for (Constructor<T> constructor : constructors) {
                if (arrayContentsEq(parameterTypes,
                                    constructor.getParameterTypes())) {
                    return getReflectionFactory().copyConstructor(constructor);
                }
            }
            throw new NoSuchMethodException(getName() + ".<init>" + argumentTypesToString(parameterTypes));
        }
    
        //
        // Other helpers and base implementation
        //
    
        private static boolean arrayContentsEq(Object[] a1, Object[] a2) {
            if (a1 == null) {
                return a2 == null || a2.length == 0;
            }
    
            if (a2 == null) {
                return a1.length == 0;
            }
    
            if (a1.length != a2.length) {
                return false;
            }
    
            for (int i = 0; i < a1.length; i++) {
                if (a1[i] != a2[i]) {
                    return false;
                }
            }
    
            return true;
        }
    
        private static Field[] copyFields(Field[] arg) {
            Field[] out = new Field[arg.length];
            ReflectionFactory fact = getReflectionFactory();
            for (int i = 0; i < arg.length; i++) {
                out[i] = fact.copyField(arg[i]);
            }
            return out;
        }
    
        private static Method[] copyMethods(Method[] arg) {
            Method[] out = new Method[arg.length];
            ReflectionFactory fact = getReflectionFactory();
            for (int i = 0; i < arg.length; i++) {
                out[i] = fact.copyMethod(arg[i]);
            }
            return out;
        }
    
        private static <U> Constructor<U>[] copyConstructors(Constructor<U>[] arg) {
            Constructor<U>[] out = arg.clone();
            ReflectionFactory fact = getReflectionFactory();
            for (int i = 0; i < out.length; i++) {
                out[i] = fact.copyConstructor(out[i]);
            }
            return out;
        }
    
        private native Field[]       getDeclaredFields0(boolean publicOnly);
        private native Method[]      getDeclaredMethods0(boolean publicOnly);
        private native Constructor<T>[] getDeclaredConstructors0(boolean publicOnly);
        private native Class<?>[]   getDeclaredClasses0();
    
        private static String        argumentTypesToString(Class<?>[] argTypes) {
            StringBuilder buf = new StringBuilder();
            buf.append("(");
            if (argTypes != null) {
                for (int i = 0; i < argTypes.length; i++) {
                    if (i > 0) {
                        buf.append(", ");
                    }
                    Class<?> c = argTypes[i];
                    buf.append((c == null) ? "null" : c.getName());
                }
            }
            buf.append(")");
            return buf.toString();
        }
    
        /** use serialVersionUID from JDK 1.1 for interoperability */
        private static final long serialVersionUID = 3206093459760846163L;
    
    
        /**
         * Class Class is special cased within the Serialization Stream Protocol.
         *
         * A Class instance is written initially into an ObjectOutputStream in the
         * following format:
         * <pre>
         *      {@code TC_CLASS} ClassDescriptor
         *      A ClassDescriptor is a special cased serialization of
         *      a {@code java.io.ObjectStreamClass} instance.
         * </pre>
         * A new handle is generated for the initial time the class descriptor
         * is written into the stream. Future references to the class descriptor
         * are written as references to the initial class descriptor instance.
         *
         * @see java.io.ObjectStreamClass
         */
        private static final ObjectStreamField[] serialPersistentFields =
            new ObjectStreamField[0];
    
    
        /**
         * Returns the assertion status that would be assigned to this
         * class if it were to be initialized at the time this method is invoked.
         * If this class has had its assertion status set, the most recent
         * setting will be returned; otherwise, if any package default assertion
         * status pertains to this class, the most recent setting for the most
         * specific pertinent package default assertion status is returned;
         * otherwise, if this class is not a system class (i.e., it has a
         * class loader) its class loader's default assertion status is returned;
         * otherwise, the system class default assertion status is returned.
         * <p>
         * Few programmers will have any need for this method; it is provided
         * for the benefit of the JRE itself.  (It allows a class to determine at
         * the time that it is initialized whether assertions should be enabled.)
         * Note that this method is not guaranteed to return the actual
         * assertion status that was (or will be) associated with the specified
         * class when it was (or will be) initialized.
         *
         * @return the desired assertion status of the specified class.
         * @see    java.lang.ClassLoader#setClassAssertionStatus
         * @see    java.lang.ClassLoader#setPackageAssertionStatus
         * @see    java.lang.ClassLoader#setDefaultAssertionStatus
         * @since  1.4
         */
        public boolean desiredAssertionStatus() {
            ClassLoader loader = getClassLoader();
            // If the loader is null this is a system class, so ask the VM
            if (loader == null)
                return desiredAssertionStatus0(this);
    
            // If the classloader has been initialized with the assertion
            // directives, ask it. Otherwise, ask the VM.
            synchronized(loader.assertionLock) {
                if (loader.classAssertionStatus != null) {
                    return loader.desiredAssertionStatus(getName());
                }
            }
            return desiredAssertionStatus0(this);
        }
    
        // Retrieves the desired assertion status of this class from the VM
        private static native boolean desiredAssertionStatus0(Class<?> clazz);
    
        /**
         * Returns true if and only if this class was declared as an enum in the
         * source code.
         *
         * @return true if and only if this class was declared as an enum in the
         *     source code
         * @since 1.5
         */
        public boolean isEnum() {
            // An enum must both directly extend java.lang.Enum and have
            // the ENUM bit set; classes for specialized enum constants
            // don't do the former.
            return (this.getModifiers() & ENUM) != 0 &&
            this.getSuperclass() == java.lang.Enum.class;
        }
    
        // Fetches the factory for reflective objects
        private static ReflectionFactory getReflectionFactory() {
            if (reflectionFactory == null) {
                reflectionFactory =
                    java.security.AccessController.doPrivileged
                        (new sun.reflect.ReflectionFactory.GetReflectionFactoryAction());
            }
            return reflectionFactory;
        }
        private static ReflectionFactory reflectionFactory;
    
        // To be able to query system properties as soon as they're available
        private static boolean initted = false;
        private static void checkInitted() {
            if (initted) return;
            AccessController.doPrivileged(new PrivilegedAction<Void>() {
                    public Void run() {
                        // Tests to ensure the system properties table is fully
                        // initialized. This is needed because reflection code is
                        // called very early in the initialization process (before
                        // command-line arguments have been parsed and therefore
                        // these user-settable properties installed.) We assume that
                        // if System.out is non-null then the System class has been
                        // fully initialized and that the bulk of the startup code
                        // has been run.
    
                        if (System.out == null) {
                            // java.lang.System not yet fully initialized
                            return null;
                        }
    
                        // Doesn't use Boolean.getBoolean to avoid class init.
                        String val =
                            System.getProperty("sun.reflect.noCaches");
                        if (val != null && val.equals("true")) {
                            useCaches = false;
                        }
    
                        initted = true;
                        return null;
                    }
                });
        }
    
        /**
         * Returns the elements of this enum class or null if this
         * Class object does not represent an enum type.
         *
         * @return an array containing the values comprising the enum class
         *     represented by this Class object in the order they're
         *     declared, or null if this Class object does not
         *     represent an enum type
         * @since 1.5
         */
        public T[] getEnumConstants() {
            T[] values = getEnumConstantsShared();
            return (values != null) ? values.clone() : null;
        }
    
        /**
         * Returns the elements of this enum class or null if this
         * Class object does not represent an enum type;
         * identical to getEnumConstants except that the result is
         * uncloned, cached, and shared by all callers.
         */
        T[] getEnumConstantsShared() {
            if (enumConstants == null) {
                if (!isEnum()) return null;
                try {
                    final Method values = getMethod("values");
                    java.security.AccessController.doPrivileged(
                        new java.security.PrivilegedAction<Void>() {
                            public Void run() {
                                    values.setAccessible(true);
                                    return null;
                                }
                            });
                    @SuppressWarnings("unchecked")
                    T[] temporaryConstants = (T[])values.invoke(null);
                    enumConstants = temporaryConstants;
                }
                // These can happen when users concoct enum-like classes
                // that don't comply with the enum spec.
                catch (InvocationTargetException | NoSuchMethodException |
                       IllegalAccessException ex) { return null; }
            }
            return enumConstants;
        }
        private volatile transient T[] enumConstants = null;
    
        /**
         * Returns a map from simple name to enum constant.  This package-private
         * method is used internally by Enum to implement
         * {@code public static <T extends Enum<T>> T valueOf(Class<T>, String)}
         * efficiently.  Note that the map is returned by this method is
         * created lazily on first use.  Typically it won't ever get created.
         */
        Map<String, T> enumConstantDirectory() {
            if (enumConstantDirectory == null) {
                T[] universe = getEnumConstantsShared();
                if (universe == null)
                    throw new IllegalArgumentException(
                        getName() + " is not an enum type");
                Map<String, T> m = new HashMap<>(2 * universe.length);
                for (T constant : universe)
                    m.put(((Enum<?>)constant).name(), constant);
                enumConstantDirectory = m;
            }
            return enumConstantDirectory;
        }
        private volatile transient Map<String, T> enumConstantDirectory = null;
    
        /**
         * Casts an object to the class or interface represented
         * by this {@code Class} object.
         *
         * @param obj the object to be cast
         * @return the object after casting, or null if obj is null
         *
         * @throws ClassCastException if the object is not
         * null and is not assignable to the type T.
         *
         * @since 1.5
         */
        @SuppressWarnings("unchecked")
        public T cast(Object obj) {
            if (obj != null && !isInstance(obj))
                throw new ClassCastException(cannotCastMsg(obj));
            return (T) obj;
        }
    
        private String cannotCastMsg(Object obj) {
            return "Cannot cast " + obj.getClass().getName() + " to " + getName();
        }
    
        /**
         * Casts this {@code Class} object to represent a subclass of the class
         * represented by the specified class object.  Checks that the cast
         * is valid, and throws a {@code ClassCastException} if it is not.  If
         * this method succeeds, it always returns a reference to this class object.
         *
         * <p>This method is useful when a client needs to "narrow" the type of
         * a {@code Class} object to pass it to an API that restricts the
         * {@code Class} objects that it is willing to accept.  A cast would
         * generate a compile-time warning, as the correctness of the cast
         * could not be checked at runtime (because generic types are implemented
         * by erasure).
         *
         * @param <U> the type to cast this class object to
         * @param clazz the class of the type to cast this class object to
         * @return this {@code Class} object, cast to represent a subclass of
         *    the specified class object.
         * @throws ClassCastException if this {@code Class} object does not
         *    represent a subclass of the specified class (here "subclass" includes
         *    the class itself).
         * @since 1.5
         */
        @SuppressWarnings("unchecked")
        public <U> Class<? extends U> asSubclass(Class<U> clazz) {
            if (clazz.isAssignableFrom(this))
                return (Class<? extends U>) this;
            else
                throw new ClassCastException(this.toString());
        }
    
        /**
         * @throws NullPointerException {@inheritDoc}
         * @since 1.5
         */
        @SuppressWarnings("unchecked")
        public <A extends Annotation> A getAnnotation(Class<A> annotationClass) {
            Objects.requireNonNull(annotationClass);
    
            return (A) annotationData().annotations.get(annotationClass);
        }
    
        /**
         * {@inheritDoc}
         * @throws NullPointerException {@inheritDoc}
         * @since 1.5
         */
        @Override
        public boolean isAnnotationPresent(Class<? extends Annotation> annotationClass) {
            return GenericDeclaration.super.isAnnotationPresent(annotationClass);
        }
    
        /**
         * @throws NullPointerException {@inheritDoc}
         * @since 1.8
         */
        @Override
        public <A extends Annotation> A[] getAnnotationsByType(Class<A> annotationClass) {
            Objects.requireNonNull(annotationClass);
    
            AnnotationData annotationData = annotationData();
            return AnnotationSupport.getAssociatedAnnotations(annotationData.declaredAnnotations,
                                                              this,
                                                              annotationClass);
        }
    
        /**
         * @since 1.5
         */
        public Annotation[] getAnnotations() {
            return AnnotationParser.toArray(annotationData().annotations);
        }
    
        /**
         * @throws NullPointerException {@inheritDoc}
         * @since 1.8
         */
        @Override
        @SuppressWarnings("unchecked")
        public <A extends Annotation> A getDeclaredAnnotation(Class<A> annotationClass) {
            Objects.requireNonNull(annotationClass);
    
            return (A) annotationData().declaredAnnotations.get(annotationClass);
        }
    
        /**
         * @throws NullPointerException {@inheritDoc}
         * @since 1.8
         */
        @Override
        public <A extends Annotation> A[] getDeclaredAnnotationsByType(Class<A> annotationClass) {
            Objects.requireNonNull(annotationClass);
    
            return AnnotationSupport.getDirectlyAndIndirectlyPresent(annotationData().declaredAnnotations,
                                                                     annotationClass);
        }
    
        /**
         * @since 1.5
         */
        public Annotation[] getDeclaredAnnotations()  {
            return AnnotationParser.toArray(annotationData().declaredAnnotations);
        }
    
        // annotation data that might get invalidated when JVM TI RedefineClasses() is called
        private static class AnnotationData {
            final Map<Class<? extends Annotation>, Annotation> annotations;
            final Map<Class<? extends Annotation>, Annotation> declaredAnnotations;
    
            // Value of classRedefinedCount when we created this AnnotationData instance
            final int redefinedCount;
    
            AnnotationData(Map<Class<? extends Annotation>, Annotation> annotations,
                           Map<Class<? extends Annotation>, Annotation> declaredAnnotations,
                           int redefinedCount) {
                this.annotations = annotations;
                this.declaredAnnotations = declaredAnnotations;
                this.redefinedCount = redefinedCount;
            }
        }
    
        // Annotations cache
        @SuppressWarnings("UnusedDeclaration")
        private volatile transient AnnotationData annotationData;
    
        private AnnotationData annotationData() {
            while (true) { // retry loop
                AnnotationData annotationData = this.annotationData;
                int classRedefinedCount = this.classRedefinedCount;
                if (annotationData != null &&
                    annotationData.redefinedCount == classRedefinedCount) {
                    return annotationData;
                }
                // null or stale annotationData -> optimistically create new instance
                AnnotationData newAnnotationData = createAnnotationData(classRedefinedCount);
                // try to install it
                if (Atomic.casAnnotationData(this, annotationData, newAnnotationData)) {
                    // successfully installed new AnnotationData
                    return newAnnotationData;
                }
            }
        }
    
        private AnnotationData createAnnotationData(int classRedefinedCount) {
            Map<Class<? extends Annotation>, Annotation> declaredAnnotations =
                AnnotationParser.parseAnnotations(getRawAnnotations(), getConstantPool(), this);
            Class<?> superClass = getSuperclass();
            Map<Class<? extends Annotation>, Annotation> annotations = null;
            if (superClass != null) {
                Map<Class<? extends Annotation>, Annotation> superAnnotations =
                    superClass.annotationData().annotations;
                for (Map.Entry<Class<? extends Annotation>, Annotation> e : superAnnotations.entrySet()) {
                    Class<? extends Annotation> annotationClass = e.getKey();
                    if (AnnotationType.getInstance(annotationClass).isInherited()) {
                        if (annotations == null) { // lazy construction
                            annotations = new LinkedHashMap<>((Math.max(
                                    declaredAnnotations.size(),
                                    Math.min(12, declaredAnnotations.size() + superAnnotations.size())
                                ) * 4 + 2) / 3
                            );
                        }
                        annotations.put(annotationClass, e.getValue());
                    }
                }
            }
            if (annotations == null) {
                // no inherited annotations -> share the Map with declaredAnnotations
                annotations = declaredAnnotations;
            } else {
                // at least one inherited annotation -> declared may override inherited
                annotations.putAll(declaredAnnotations);
            }
            return new AnnotationData(annotations, declaredAnnotations, classRedefinedCount);
        }
    
        // Annotation types cache their internal (AnnotationType) form
    
        @SuppressWarnings("UnusedDeclaration")
        private volatile transient AnnotationType annotationType;
    
        boolean casAnnotationType(AnnotationType oldType, AnnotationType newType) {
            return Atomic.casAnnotationType(this, oldType, newType);
        }
    
        AnnotationType getAnnotationType() {
            return annotationType;
        }
    
        Map<Class<? extends Annotation>, Annotation> getDeclaredAnnotationMap() {
            return annotationData().declaredAnnotations;
        }
    
        /* Backing store of user-defined values pertaining to this class.
         * Maintained by the ClassValue class.
         */
        transient ClassValue.ClassValueMap classValueMap;
    
        /**
         * Returns an {@code AnnotatedType} object that represents the use of a
         * type to specify the superclass of the entity represented by this {@code
         * Class} object. (The <em>use</em> of type Foo to specify the superclass
         * in '...  extends Foo' is distinct from the <em>declaration</em> of type
         * Foo.)
         *
         * <p> If this {@code Class} object represents a type whose declaration
         * does not explicitly indicate an annotated superclass, then the return
         * value is an {@code AnnotatedType} object representing an element with no
         * annotations.
         *
         * <p> If this {@code Class} represents either the {@code Object} class, an
         * interface type, an array type, a primitive type, or void, the return
         * value is {@code null}.
         *
         * @return an object representing the superclass
         * @since 1.8
         */
        public AnnotatedType getAnnotatedSuperclass() {
            if (this == Object.class ||
                    isInterface() ||
                    isArray() ||
                    isPrimitive() ||
                    this == Void.TYPE) {
                return null;
            }
    
            return TypeAnnotationParser.buildAnnotatedSuperclass(getRawTypeAnnotations(), getConstantPool(), this);
        }
    
        /**
         * Returns an array of {@code AnnotatedType} objects that represent the use
         * of types to specify superinterfaces of the entity represented by this
         * {@code Class} object. (The <em>use</em> of type Foo to specify a
         * superinterface in '... implements Foo' is distinct from the
         * <em>declaration</em> of type Foo.)
         *
         * <p> If this {@code Class} object represents a class, the return value is
         * an array containing objects representing the uses of interface types to
         * specify interfaces implemented by the class. The order of the objects in
         * the array corresponds to the order of the interface types used in the
         * 'implements' clause of the declaration of this {@code Class} object.
         *
         * <p> If this {@code Class} object represents an interface, the return
         * value is an array containing objects representing the uses of interface
         * types to specify interfaces directly extended by the interface. The
         * order of the objects in the array corresponds to the order of the
         * interface types used in the 'extends' clause of the declaration of this
         * {@code Class} object.
         *
         * <p> If this {@code Class} object represents a class or interface whose
         * declaration does not explicitly indicate any annotated superinterfaces,
         * the return value is an array of length 0.
         *
         * <p> If this {@code Class} object represents either the {@code Object}
         * class, an array type, a primitive type, or void, the return value is an
         * array of length 0.
         *
         * @return an array representing the superinterfaces
         * @since 1.8
         */
        public AnnotatedType[] getAnnotatedInterfaces() {
             return TypeAnnotationParser.buildAnnotatedInterfaces(getRawTypeAnnotations(), getConstantPool(), this);
        }
    }
    Class.java

      4.1 获取类名信息

        Class类的成员方法 getSimpleName、getName 可以获取到类名相关的信息

        技巧01:虽然参数类型是Object类型,但是实际上传递过来的实参是哪个类的对象,c就是哪个类的类类型

          例如:传入的 String 的一个实例,那么 c 就是 String 的类类型

        public static void printClassInfo(Object object) {
            // 01 获取类类型
            Class c = object.getClass();
    
            // 02 调用Class实例的相关方法获取类名信息
            System.out.println("类的名称为:" + c.getSimpleName());
            System.out.println("类的全名为:" + c.getName());
        }

      4.2 获取方法信息

        技巧01:所有的方法都是Method的实例

        技巧02:Class类的getMethods获取的是本类以及父类中public修饰的方法;Class类的getDeclaredMethods()获取到的是本类中所有的方法【不包括父类的】

        技巧03:Method类的相关成员方法 

          getReturnType -> 获取方法返回类型 -> 返回值是一个Class实例

          getName -> 获取方法名 -> 返回值是一个String实例

          getParameterTypes -> 获取方法的参数类型列表 -> 返回值是一个 Class实例 组成的数组

        public static void printMethodsInfo(Object object) {
            // 01 获取类类型
            Class c = object.getClass();
            // 技巧01:虽然参数类型是Object类型,但是实际上传递过来的实参是哪个类的对象,c就是哪个类的类类型
            // 例如:传入的 String 的一个实例,那么 c 就是 String 的类类型
    
            // 02 获取所有的方法组成的数组
            // 技巧02:所有的方法都是Method的实例
            // 技巧03:getMethods获取的是本类以及父类中public修饰的方法;getDeclaredMethods()获取到的是本类中所有的方法【不包括父类的】
            Method[] methods = c.getMethods();
            for (Integer i = 0; i < methods.length; i++) {
                // 0201 获取方法返回值类型
                Class returnType = methods[i].getReturnType();
                System.out.println("第" + i + "个方法的返回值类型为:" + returnType.getName());
    
                // 0202 获取方法名称
                String methodName = methods[i].getName();
                System.out.println("第" + i + "个方法的方法名为:" + methodName);
    
                // 0203 获取方法参数
                Class[] paramTypes = methods[i].getParameterTypes();
                for (Integer j = 0; j < paramTypes.length; j++) {
                    System.out.println("第" + i + "个方法的第" + j + "个参数类型为:" + paramTypes[j].getName());
                }
            }
        }
    View Code

      4.3 获取属性信息

        技巧01:所有属性都是Filed的实例

        技巧02:Class类的getFields获取public修饰的成员变量,Class类的getDeclaredFields获取本类声明的所有成员

        技巧03:Field类的相关方法

          getType -> 获取属性类型 -> 返回值是一个Class实例

          getName -> 获取属性名称 -> 返回值是一个String实例

        public static void printFieldInfo(Object object) {
            // 01 获取类类型
            Class c = object.getClass();
    
            Field[] fields = c.getFields();
    
            for (Integer i = 0; i < fields.length; i++) {
                String fieldName = fields[i].getName();
                String fieldType = fields[i].getType().getName();
                System.out.println("第" + i + "个成员变量的信息为:字段类型 -> " + fieldType + " 字段名称 -> " + fieldName);
            }
        }
    View Code

      4.4 获取构造器信息

        技巧01:所有的构造器都是Constructor的实例

        技巧02:Class类的 getConstructors 获取本类和父类中有pulbic修饰的构造器,Class类的 getDeclaredConstructors 获取本类中声明的构造器

        技巧03:Constructor类的相关方法

          getName -> 获取构造器名称 -> 返回的是一个String实例

          getParameterTypes -> 获取构造器参数类型列表 -> 返回的是一个Class实例组成的数组

        public static void printConstructorInfo(Object object) {
    
            // 01 获取类类型
            Class c = object.getClass();
    
            Constructor[] constructors = c.getConstructors();
            for (Integer i = 0; i < constructors.length; i++) {
                String constructorName = constructors[i].getName();
                System.out.println("第" + i + "个构造函数逇名称为:" + constructorName);
    
                Class[] paramTypes = constructors[i].getParameterTypes();
                for (Integer j = 0; j < paramTypes.length; j++) {
                    System.out.println("第" + i + "个构造函数的" + "第" + j + "个参数类型为:" + paramTypes[j].getName() );
                }
    
            }
    
        }
    View Code

      4.5 代码汇总

    package demo_test02;
    
    import org.omg.CORBA.OBJECT_NOT_EXIST;
    
    import java.lang.reflect.Constructor;
    import java.lang.reflect.Field;
    import java.lang.reflect.Method;
    import java.util.ArrayList;
    
    /**
     * @author 王杨帅
     * @create 2018-08-06 10:34
     * @desc
     **/
    public class Test01 {
    
        public static void main(String[] args) {
            Integer i = 3;
            ClassUtil.printClassInfo(i);
            System.out.println("============");
    
            ClassUtil.printMethodsInfo(i);
            System.out.println("============");
    
            ClassUtil.printFieldInfo(i);
            System.out.println("============");
    
            ClassUtil.printConstructorInfo(i);
    
        }
    
    }
    
    class ClassUtil {
    
        public static void printClassInfo(Object object) {
            // 01 获取类类型
            Class c = object.getClass();
    
            // 02 调用Class实例的相关方法获取类名信息
            System.out.println("类的名称为:" + c.getSimpleName());
            System.out.println("类的全名为:" + c.getName());
        }
    
        public static void printMethodsInfo(Object object) {
            // 01 获取类类型
            Class c = object.getClass();
            // 技巧01:虽然参数类型是Object类型,但是实际上传递过来的实参是哪个类的对象,c就是哪个类的类类型
            // 例如:传入的 String 的一个实例,那么 c 就是 String 的类类型
    
            // 02 获取所有的方法组成的数组
            // 技巧02:所有的方法都是Method的实例
            // 技巧03:getMethods获取的是本类以及父类中public修饰的方法;getDeclaredMethods()获取到的是本类中所有的方法【不包括父类的】
            Method[] methods = c.getMethods();
            for (Integer i = 0; i < methods.length; i++) {
                // 0201 获取方法返回值类型
                Class returnType = methods[i].getReturnType();
                System.out.println("第" + i + "个方法的返回值类型为:" + returnType.getName());
    
                // 0202 获取方法名称
                String methodName = methods[i].getName();
                System.out.println("第" + i + "个方法的方法名为:" + methodName);
    
                // 0203 获取方法参数
                Class[] paramTypes = methods[i].getParameterTypes();
                for (Integer j = 0; j < paramTypes.length; j++) {
                    System.out.println("第" + i + "个方法的第" + j + "个参数类型为:" + paramTypes[j].getName());
                }
            }
        }
    
        public static void printFieldInfo(Object object) {
            // 01 获取类类型
            Class c = object.getClass();
    
            Field[] fields = c.getFields();
    
            for (Integer i = 0; i < fields.length; i++) {
                String fieldName = fields[i].getName();
                String fieldType = fields[i].getType().getName();
                System.out.println("第" + i + "个成员变量的信息为:字段类型 -> " + fieldType + " 字段名称 -> " + fieldName);
            }
        }
    
        public static void printConstructorInfo(Object object) {
    
            // 01 获取类类型
            Class c = object.getClass();
    
            Constructor[] constructors = c.getConstructors();
            for (Integer i = 0; i < constructors.length; i++) {
                String constructorName = constructors[i].getName();
                System.out.println("第" + i + "个构造函数逇名称为:" + constructorName);
    
                Class[] paramTypes = constructors[i].getParameterTypes();
                for (Integer j = 0; j < paramTypes.length; j++) {
                    System.out.println("第" + i + "个构造函数的" + "第" + j + "个参数类型为:" + paramTypes[j].getName() );
                }
    
            }
    
        }
    
    }
    View Code

    5 方法反射

       Method类的invoke方法可以执行一个实例的方法;

      一个Class实例可以通过getMethod方法获取到单个的Method实例。

      5.1 准备类

    class Foo {
    
        public void print() {
            System.out.println("渝足");
        }
    
        public void print(Integer a, Integer b) {
            System.out.println(a + b);
        }
    
        public void print(String a, String b) {
            System.out.println(a.toUpperCase() + " , " + b.toLowerCase());
        }
    }
    Foo.java

      5.2 获取Method实例并用其调用Foo实例的方法

        》创建一个Foo实例

        》Method实例

    // 根据方法名和方法类型列表获取方法对象
    Method method0 = c.getMethod("print", new Class[]{String.class, String.class});

        》利用Method实例调用Foo实例的方法

                // 执行方法对象
                method0.invoke(foo, new String[]{"hello", "Fury"});

      5.3 代码汇总

    package demo06_reflect.case04_method;
    
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    
    /**
     * @author 王杨帅
     * @create 2018-08-06 9:21
     * @desc 方法反射
     **/
    public class Method_Demo01 {
    
        public static void main(String[] args) {
    
            Foo foo = new Foo();
    //        foo.print(1, 2);
    //        foo.print("hello", "word");
    
            Class c = foo.getClass();
            try {
                // 根据方法名和方法类型列表获取方法对象
                Method method0 = c.getMethod("print", new Class[]{String.class, String.class});
                // 执行方法对象
                method0.invoke(foo, new String[]{"hello", "Fury"});
    //            Method method = c.getMethod("print", String.class, String.class);
    //            method.invoke(foo, "good", "boy");
                System.out.println("====================");
    
                Method method1 = c.getMethod("print", Integer.class, Integer.class);
                method1.invoke(foo, 3, 4);
                Method method2 = c.getMethod("print", new Class[]{Integer.class, Integer.class});
                method2.invoke(foo, new Integer[]{4, 4});
                System.out.println("====================");
    
    //            Method method3 = c.getMethod("print");
    //            method3.invoke(foo);
                Method method4 = c.getMethod("print", new Class[]{});
                method4.invoke(foo, new Object[]{});
                System.out.println("====================");
    
    
            } catch (NoSuchMethodException e) {
                e.printStackTrace();
            } catch (IllegalAccessException e) {
                e.printStackTrace();
            } catch (InvocationTargetException e) {
                e.printStackTrace();
            }
    
        }
    
    }
    
    class Foo {
    
        public void print() {
            System.out.println("渝足");
        }
    
        public void print(Integer a, Integer b) {
            System.out.println(a + b);
        }
    
        public void print(String a, String b) {
            System.out.println(a.toUpperCase() + " , " + b.toLowerCase());
        }
    }
    View Code

      5.4 方法反射的应用

        列表的泛型其实是在编译阶段起作用的;所以在运行阶段可以利用方法反射去掉用List的add方法,从而绕过泛型的限制

    package demo06_reflect.case04_method;
    
    import java.lang.reflect.InvocationTargetException;
    import java.lang.reflect.Method;
    import java.util.ArrayList;
    import java.util.List;
    
    /**
     * @author 王杨帅
     * @create 2018-08-06 9:33
     * @desc 方法反射的应用
     **/
    public class Method_Demo02 {
    
       public static void main(String[] args) {
           List list01 = new ArrayList();
           list01.add(333);
           list01.add("warrior");
           System.out.println(list01);
    
           List<String> list02 = new ArrayList<>();
           list02.add("warrior");
    //       list02.add(333);
           System.out.println(list02);
           System.out.println("===============================");
    
    
           Class c01 = list01.getClass(); // 运行阶段执行
           Class c02 = list02.getClass();
    
           System.out.println(c01 == c02); // 说明列表的泛型只是作用于编译阶段
           System.out.println("===============================");
    
           Class c = list02.getClass();
           try {
               // 获取Method实例
               Method method = c.getMethod("add", Object.class);
               // 利用Method实例调用List的add方法
               method.invoke(list02, 333);
               System.out.println(list02);
           } catch (NoSuchMethodException e) {
               e.printStackTrace();
           } catch (IllegalAccessException e) {
               e.printStackTrace();
           } catch (InvocationTargetException e) {
               e.printStackTrace();
           }
           System.out.println("===============================");
    
       }
    }
    View Code

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  • 原文地址:https://www.cnblogs.com/NeverCtrl-C/p/9416850.html
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