Java学习路线-57：静态代理和动态代理

抽象角色 接口或者抽象类
真实角色 被代理的角色
代理角色 代理真实角色，一般会做一些附属操作
客户角色 使用代理角色进行一些操作
AbstractObject
    - RealObject
    - Proxy
Client

package com.pengshiyu.proxy;
// 租借接口
public interface IRent {
    void rent();
}

package com.pengshiyu.proxy;
public class Host implements IRent{
    @Override
    public void rent() {
        System.out.println("房东租房");
    }
}

package com.pengshiyu.proxy;
// 中介
public class Proxy implements IRent{
    private Host host;
    public Proxy(Host host){
        this.host = host;
    }
    @Override
    public void rent() {
        this.beforeRent();
        this.host.rent();
        this.afterRent();
    }
    private void beforeRent(){
        System.out.println("中介带看房");
    }
    private void afterRent(){
        System.out.println("签订合同");
    }
}

package com.pengshiyu.proxy;
// 客户
public class Client {
    public static void main(String[] args) {
        Host host = new Host();
        Proxy proxy = new Proxy(host);
        proxy.rent();
    }
}

package com.pengshiyu.proxy;
public interface IVehicle {
    void run();
}

package com.pengshiyu.proxy;
public class Car implements IVehicle {
    public void run() {
        System.out.println("Car会跑");
    }
}

package com.pengshiyu.proxy;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
public class VehicleInvocationHandler implements InvocationHandler {
    private Object target;
    public VehicleInvocationHandler(Object target){
        this.target = target;
    }
    @Override
    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
        System.out.println("---------before-------");
        Object result = method.invoke(target, args);
        System.out.println("---------after-------");
        return result;
    }
}

package com.pengshiyu.proxy;
import java.lang.reflect.Proxy;
// 客户
public class Client {
    public static void main(String[] args) {
        IVehicle car = new Car();
        IVehicle carProxy = (IVehicle)Proxy.newProxyInstance(
                car.getClass().getClassLoader(),
                car.getClass().getInterfaces(),
                new VehicleInvocationHandler(car)
        );
        carProxy.run();
    }
}