1.创建一个接口

package Mydynamicproxy1;

public interface Star {

    public abstract String sing(String str);
    public abstract void dance(String str);
}

2.创建一个BigStar类，要实现Star这个接口

package Mydynamicproxy1;

public class BigStar implements Star{

    private String num;

    @Override
    public String sing(String song){
        System.out.println("正在唱歌"+song);
        return "唱完了谢谢";
    }
    @Override
    public void dance(String dan){
        System.out.println("正在跳舞"+dan);
    }


    public BigStar() {
    }

    public BigStar(String num) {
        this.num = num;
    }

    /**
     * 获取
     * @return num
     */
    public String getNum() {
        return num;
    }

    /**
     * 设置
     * @param num
     */
    public void setNum(String num) {
        this.num = num;
    }

    public String toString() {
        return "BigStar{num = " + num + "}";
    }
}

 3.代理的类

package Mydynamicproxy1;

import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;

public class ProxyUtil {
    public static Star createStar(BigStar bigstar) {

        Star star = (Star)Proxy.newProxyInstance(
                ProxyUtil.class.getClassLoader(),
                new Class[]{Star.class},
                new InvocationHandler() {
                    @Override
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {

                        if("sing".equals(method.getName())){
                            System.out.println("准备话筒，收钱");
                        }else{
                            System.out.println("准备场地，收钱");
                        }
                        return method.invoke(bigstar, args);
                    }
                }


        );


        return star;
    }

}

4.Test类

package Mydynamicproxy1;

public class Test {
    public static void main(String[] args) {

        BigStar bigStar=new BigStar("cxk");
        Star proxy=ProxyUtil.createStar(bigStar);

        System.out.println(proxy.sing("aaa"));

    }
}