动态代理

所谓动态代理，即通过代理类Proxy的代理接口和实现类之间可以不直接发生联系，而可以在运行期实现动态关联
代理类要实现InvocationHandler接口的invoke方法

1、被代理类接口

public interface Student {
    public String study();
}

2、被代理类

public class Scholar implements Student {
    @Override
    public String study() {
        System.out.println("学习java");
        return "项目有所进展";
    }
}

3、代理类

public class MyInvocationHandler implements InvocationHandler {
    Scholar scholar;
    public MyInvocationHandler(Scholar scholar) {
        super();
        this.scholar = scholar;
    }

    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        Object invoke = method.invoke(scholar, args);
        return invoke;
    }
}

4、测试类

public class Teacher {
    public static void main(String[] args) {
        Scholar scholar = new Scholar();
        InvocationHandler invocationHandler = new MyInvocationHandler(scholar);
        Student s = (Student)Proxy.newProxyInstance(Scholar.class.getClassLoader(),
                Scholar.class.getInterfaces(), invocationHandler);
        System.out.println(s.study());
    }

}