从代理对象中获取原始对象

使用JDK动态代理时，有时需要获取原始对象，那怎么通过代理对象获取原始对象呢？

接口

public interface Person {
    void doWork();

}

实现类

public class PersonImpl implements Person {
    public void doWork() {
        System.out.println("testssttt");
    }
}

代理类

public class PersonProxy implements InvocationHandler {

    private Person target;

    public Object getInstance(Person person){
        this.target = person;
        return Proxy.newProxyInstance(person.getClass().getClassLoader(),person.getClass().getInterfaces(),this);
    }

    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        method.invoke(target,null);
        return null;
    }
}

测试方法：

/**
     * 从代理对象中获取原始对象
     * @throws Exception
     */
    @Test
    public void testProxy() throws Exception {
        Person person = (Person) new PersonProxy().getInstance(new PersonImpl());
//        person.doWork();
        System.out.println(person.getClass());

        System.out.println(getTarget(person));

    }

    public Object getTarget(Object proxy) throws Exception {
        Field field = proxy.getClass().getSuperclass().getDeclaredField("h");
        field.setAccessible(true);
        //获取指定对象中此字段的值
        PersonProxy personProxy = (PersonProxy) field.get(proxy); //获取Proxy对象中的此字段的值
        Field person = personProxy.getClass().getDeclaredField("target");
        person.setAccessible(true);
        return person.get(personProxy);
    }

测试结果如图，成功获取原始对象