Spring进阶之路(10)-Advice简介以及通过cglib生成AOP代理对象

Advice简介

通过cglib生成AOP代理对象

package com.siti.spring20160315;

public class User {

	private String userName;
	private String password;
	
	public User(){}
	
	public User(String userName, String password) {
		super();
		this.userName = userName;
		this.password = password;
	}
	
	public String getUserName() {
		return userName;
	}
	public void setUserName(String userName) {
		this.userName = userName;
	}
	public String getPassword() {
		return password;
	}
	public void setPassword(String password) {
		this.password = password;
	}

	public void saySth() {
		System.out.println("hello!");
	}
}

package com.siti.spring20160315;

import java.lang.reflect.Method;
import org.springframework.cglib.proxy.Enhancer;
import org.springframework.cglib.proxy.InvocationHandler;

public class MyProxy4AOPObject implements InvocationHandler{

	private Object targetObj;
	
	public Object getProxyObject(Object targetObj){
		this.targetObj = targetObj;
		
		Enhancer enhance = new Enhancer();
		// 将目标类设置为代理对象的父类，产生目标类的子类，这个子类覆盖所有父类的非final修饰的方法
		enhance.setSuperclass(this.targetObj.getClass());
		// 设置回调，可以单独建立一个类实现InvocationHandler接口实现里面的invoke方法
		enhance.setCallback(this);
		
		return enhance.create();
	}

	@Override
	public Object invoke(Object proxy, Method method, Object[] args)
			throws Throwable {
		
		User user = (User)this.targetObj;
		Object result = null;
		try{
			// 拦截，符合要求的才允许运行
			if(user.getUserName() != null && user.getUserName() != ""){
				// -->Before
				result = method.invoke(this.targetObj, args);
				// -->AfterReturning
			}
		}catch (Exception e) {
			// -->AfterThrowing
		}finally{
			// -->After
		}
		
		return result;
	}

}

package com.siti.spring20160315;

public class MainTest {

	public static void main(String[] args) {
		User user = new User("wy", "wy");
		MyProxy4AOPObject myProxy4AOPObject = new MyProxy4AOPObject();
		User us = (User) myProxy4AOPObject.getProxyObject(user);
		us.saySth();
	}
}