java映射

虚拟机通过得到类的字节码文件，从而创建对象。在java代码中可用Class类中的方法进行实现，

package javase;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

public class ReflextDemo {
    
    public static void method2() throws ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {
        
        String name = "test.Person";//把类名的路径存到字符串
        Class clazz = Class.forName(name);//通过路径拿到字节码文件，创建对象
        Constructor<Person> con = clazz.getConstructor(String.class,int.class);//获取构造器
        Object obj = con.newInstance("小强",10);//创建实例
        
    }

    public static void method1() throws ClassNotFoundException, InstantiationException, IllegalAccessException {
        
        String name = "test.Person";//把类名的路径存到字符串
        Class clazz = Class.forName(name);//通过路径拿到字节码文件，创建对象
        Object obj = clazz.newInstance();//创建实例
        
    }
    
    public static void main(String[] args) throws ClassNotFoundException, NoSuchMethodException, SecurityException, InstantiationException, IllegalAccessException, IllegalArgumentException, InvocationTargetException {

        method2();
        
    }

}