## 一、概述 AOP的實現方法在上兩篇博客中已經用了兩種方法來實現現在的問題來了雖然我們利用AOP，那么客戶端如何信息傳遞？利用JoinPoint接口來實現客戶端給具體實現類的傳遞參數。 ## 二、代碼演示。 目錄結構：  SecurityHandler.java ~~~ package com.tgb.spring; import org.aspectj.lang.JoinPoint; public class SecurityHandler{ private void checkSecurity(JoinPoint joinPoint){ for (int i = 0; i < joinPoint.getArgs().length; i++) { System.out.println(joinPoint.getArgs()[i]); } System.out.println(joinPoint.getSignature().getName()); System.out.println("=====checkSecurity===="); } } ~~~ Client.java ~~~ package com.tgb.spring; import org.springframework.beans.factory.BeanFactory; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.tgb.spring.UserManager; public class Client { public static void main(String[] args) { BeanFactory factory=new ClassPathXmlApplicationContext("applicationContext.xml"); UserManager userManager=(UserManager) factory.getBean("userManager"); userManager.addUser("張三", "123"); //userManager.delUser(1); } } ~~~ UserManager.java ~~~ package com.tgb.spring; public interface UserManager { public void addUser(String username,String password); public void delUser(int userId); public String findUserById(int userId); public void modifyUser(int userId,String username,String password); } ~~~ UserManagerImpl.java ~~~ package com.tgb.spring; public class UserManagerImpl implements UserManager { public void addUser(String username, String password) { //checkSecurity(); System.out.println("===UserManager.addUser==="); } public void delUser(int userId) { //checkSecurity(); System.out.println("===UserManager.delUser==="); } public String findUserById(int userId) { //checkSecurity(); System.out.println("===UserManager.findUserById==="); return "張三"; } public void modifyUser(int userId, String username, String password) { //checkSecurity(); System.out.println("===UserManager.modifyUser==="); } // private void checkSecurity(){ // System.out.println("checkSecurity"); // // } } ~~~ applicationContext.xml ~~~ <?xml version="1.0" encoding="UTF-8"?> <beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:aop="http://www.springframework.org/schema/aop" xmlns:tx="http://www.springframework.org/schema/tx" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-2.0.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-2.0.xsd http://www.springframework.org/schema/tx http://www.springframework.org/schema/tx/spring-tx-2.0.xsd"> <bean id="userManager" class="com.tgb.spring.UserManagerImpl" /> <bean id="securityHandler" class="com.tgb.spring.SecurityHandler"/> <aop:config> <aop:aspect id="securityAspect" ref="securityHandler"> <aop:pointcut id="addAddMethod" expression="execution(* com.tgb.spring.*.*(..))" /> <aop:before method="checkSecurity" pointcut-ref="addAddMethod" /> </aop:aspect> </aop:config> </beans> ~~~ 效果圖：  ## 三、總結。 我們可以通過Advice中添加一個JoinPoint參數，這個值會由spring自動傳入，從JoinPoint中可以取得。