静态代理、动态代理（JDK动态代理，Cglib动态代理）（2）

package com.proxy;
public interface IUserDao {
    public void save();
}

package com.proxy;
public class UserDao implements IUserDao{
    @Override
    public void save() {
        System.out.println("保存数据");
    }
}

package com.proxy;
import java.lang.reflect.InvocationHandler;
import java.lang.reflect.Method;
import java.lang.reflect.Proxy;
public class ProxyFactory {
    private Object target;// 维护一个目标对象
    public ProxyFactory(Object target) {
        this.target = target;
    }
    // 为目标对象生成代理对象
    public Object getProxyInstance() {
        return Proxy.newProxyInstance(target.getClass().getClassLoader(), target.getClass().getInterfaces(),
                new InvocationHandler() {
                    @Override
                    public Object invoke(Object proxy, Method method, Object[] args) throws Throwable {
                        System.out.println("开启事务");
                        // 执行目标对象方法
                        Object returnValue = method.invoke(target, args);
                        System.out.println("提交事务");
                        return null;
                    }
                });
    }
}

package com.proxy;
import org.junit.Test;
public class TestProxy {
    @Test
    public void testDynamicProxy (){
        IUserDao target = new UserDao();
        System.out.println(target.getClass());  //输出目标对象信息
        IUserDao proxy = (IUserDao) new ProxyFactory(target).getProxyInstance();
        System.out.println(proxy.getClass());  //输出代理对象信息
        proxy.save();  //执行代理方法
    }
}

class com.proxy.UserDao
class com.sun.proxy.$Proxy4
开启事务
保存数据
提交事务

<dependency>
    <groupId>cglib</groupId>
    <artifactId>cglib</artifactId>
    <version>3.2.5</version>
</dependency>

package com.cglib;
public class UserDao{
    public void save() {
        System.out.println("保存数据");
    }
}