Spring视频学习（六）JDK和cglib实现AOP

一、JDK的AOP实现--基于接口的代理模式

package cn.itcast.aop;

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

import cn.itcast.service.impl.PersonServiceBean;

public class JDKProxyFactory implements InvocationHandler{
	private Object targetObject;
	
	public Object createProxyIntance(Object targetObject){
		this.targetObject = targetObject;
		return Proxy.newProxyInstance(this.targetObject.getClass().getClassLoader(), 
				this.targetObject.getClass().getInterfaces(), this);
	}

	public Object invoke(Object proxy, Method method, Object[] args)
			throws Throwable {//环绕通知
		PersonServiceBean bean = (PersonServiceBean) this.targetObject;
		Object result = null; 
		if(bean.getUser()!=null){
			//..... advice()-->前置通知
			System.out.println("before");
			try {
				result = method.invoke(targetObject, args);
				// afteradvice() -->后置通知
				System.out.println("after");
			} catch (RuntimeException e) {
				//exceptionadvice()--> 例外通知
			}finally{
				//finallyadvice(); -->最终通知
			}
		}else{
			System.out.println("无权调用");
		}
		return result;
	}

}

二、cglib的AOP实现--基于继承的代理模式

package cn.itcast.aop;

import java.lang.reflect.Method;

import cn.itcast.service.impl.PersonServiceBean;

import net.sf.cglib.proxy.Enhancer;
import net.sf.cglib.proxy.MethodInterceptor;
import net.sf.cglib.proxy.MethodProxy;

public class CGlibProxyFactory implements MethodInterceptor{
	private Object targetObject;
	
	public Object createProxyIntance(Object targetObject){
		this.targetObject = targetObject;
		Enhancer enhancer = new Enhancer();
		enhancer.setSuperclass(this.targetObject.getClass());//非final
		enhancer.setCallback(this);
		return enhancer.create();
	}

	public Object intercept(Object proxy, Method method, Object[] args,
			MethodProxy  methodProxy) throws Throwable {
		PersonServiceBean bean = (PersonServiceBean) this.targetObject;
		Object result = null;
		if(bean.getUser()!=null){
			result = methodProxy.invoke(targetObject, args);
		}
		return result;
	}
}

 

三、Junit测试

package junit.test;


import org.junit.BeforeClass;
import org.junit.Test;

import cn.itcast.aop.CGlibProxyFactory;
import cn.itcast.aop.JDKProxyFactory;
import cn.itcast.service.PersonService;
import cn.itcast.service.impl.PersonServiceBean;

public class AOPTest {

	@BeforeClass
	public static void setUpBeforeClass() throws Exception {
	}

	@Test public void proxyTest(){
		JDKProxyFactory factory = new JDKProxyFactory();
		PersonService service = (PersonService) factory.createProxyIntance(new PersonServiceBean());
		service.save("888");
	}
	
	@Test public void proxyTest2(){
		CGlibProxyFactory factory = new CGlibProxyFactory();
		PersonServiceBean service = (PersonServiceBean) factory.createProxyIntance(new PersonServiceBean("xxx"));
		service.save("999");
	}
}