JavaSE：反射机制

1.　　

Package getPackage()	获取所在的包信息
Class<? super T>getSuperclass()	获取继承的父类信息
Class<?>[] getInterfaces()	获取实现的所有接口
Annotation[] getAnnotations()	获取注解信息
Type[] getGenericInterface()	获取泛型信息

2. 代码示例

import java.io.Serializable;

@MyAnnotation
public class Student<T, E> extends Person implements Comparable<String>, Serializable {

    @Override
    public int compareTo(String o) {
        return 0;
    }
}

@Retention(RetentionPolicy.RUNTIME)
public @interface MyAnnotation {
}

public class StudentTest {

    public static void main(String[] args) throws Exception {

        // 获取Student类型的Class对象
        Class c1 = Class.forName("com.lagou.task20.Student");
        System.out.println("获取到的包信息是：" + c1.getPackage());
        System.out.println("获取到的父类信息是：" + c1.getSuperclass());

        System.out.println("-------------------------------------------------");
        System.out.println("获取到的接口信息是：");
        Class[] interfaces = c1.getInterfaces();
        for (Class ct : interfaces) {
            System.out.print(ct + " ");
        }
        System.out.println();

        System.out.println("-------------------------------------------------");
        System.out.println("获取到的注解信息是：");
        Annotation[] annotations = c1.getAnnotations();
        for (Annotation at : annotations) {
            System.out.print(at + " ");
        }
        System.out.println();

        System.out.println("-------------------------------------------------");
        System.out.println("获取到的泛型信息是：");
        Type[] genericInterfaces = c1.getGenericInterfaces();
        for (Type tt : genericInterfaces) {
            System.out.print(tt + " ");
        }
        System.out.println();
    }
}

运行效果

3. 反射机制 - 小结

4.反射机制 - 练习