Spring Annotation注解进行aop的学习

使用Maven管理项目，pom文件为：

 <project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
     xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
     <groupId>com.dzg</groupId>
     <artifactId>spring_study</artifactId>
     <version>0.0.1-SNAPSHOT</version>
     <properties>
         <maven.compiler.source>1.8</maven.compiler.source>
         <maven.compiler.target>1.8</maven.compiler.target>
         <maven.compiler.compilerVersion>1.8</maven.compiler.compilerVersion>
     </properties>

     <dependencies>
         <dependency>
             <groupId>org.springframework</groupId>
             <artifactId>spring-context</artifactId>
             <version>4.3.2.RELEASE</version>
         </dependency>
         <!-- https://mvnrepository.com/artifact/junit/junit -->
         <dependency>
             <groupId>junit</groupId>
             <artifactId>junit</artifactId>
             <version>4.12</version>
         </dependency>
         <!-- https://mvnrepository.com/artifact/org.aspectj/aspectjrt -->
         <dependency>
             <groupId>org.aspectj</groupId>
             <artifactId>aspectjrt</artifactId>
             <version>1.8.9</version>
         </dependency>
         <!-- https://mvnrepository.com/artifact/org.aspectj/aspectjweaver -->
         <dependency>
             <groupId>org.aspectj</groupId>
             <artifactId>aspectjweaver</artifactId>
             <version>1.8.9</version>
         </dependency>
         <!-- https://mvnrepository.com/artifact/aopalliance/aopalliance -->
         <dependency>
             <groupId>aopalliance</groupId>
             <artifactId>aopalliance</artifactId>
             <version>1.0</version>
         </dependency>

     </dependencies>
 </project>

pom.xml

建立User类：

 package com.dzg.spring.model;

 public class User {
     private int id;
     private String password;
     private String username;
     public int getId() {
         return id;
     }
     public String getPassword() {
         return password;
     }
     public String getUsername() {
         return username;
     }
     public void setId(int id) {
         this.id = id;
     }
     public void setPassword(String password) {
         this.password = password;
     }
     public void setUsername(String username) {
         this.username = username;
     }
 }

User.java

建立UserService类：

 package com.dzg.spring.service;

 import javax.annotation.Resource;

 import org.springframework.stereotype.Component;

 import com.dzg.spring.dao.UserDAO;
 import com.dzg.spring.model.User;

 @Component
 public class UserService {

     private UserDAO userDAO;

     public void add(User user) {
         userDAO.save(user);
     }

     public UserDAO getUserDAO() {
         return userDAO;
     }

     public UserService() {

     }

     @Resource(name = "u")
     public void setUserDAO(UserDAO userDAO) {
         this.userDAO = userDAO;
     }

 }

UserService.java

建立UserDAO接口类：

 package com.dzg.spring.dao;

 import com.dzg.spring.model.User;

 public interface UserDAO {
     public void save(User user);
 }

UserDAO.java

建立实现UserDAO接口的实体类UserDAOImpl类：

 package com.dzg.spring.dao.impl;

 import org.springframework.stereotype.Component;

 import com.dzg.spring.dao.UserDAO;
 import com.dzg.spring.model.User;

 @Component("u")
 public class UserDAOImpl implements UserDAO {

     @Override
     public void save(User user) {
         System.out.println("user saved!");
     }

 }

UserDAOImpl.java

建立LogInterceptor类：

 package com.dzg.spring.aop;

 import org.aspectj.lang.annotation.Aspect;
 import org.aspectj.lang.annotation.Before;
 import org.springframework.stereotype.Component;

 @Aspect
 @Component("log")
 public class LogInterceptor {

     @Before("execution(public void com.dzg.spring.dao.impl.UserDAOImpl.save(com.dzg.spring.model.User))")
     public void beforeMethod() {
         System.out.println("save start!");
     }

 }

LogInterceptor.java

beans.xml文件：

 <?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:context="http://www.springframework.org/schema/context"
     xmlns:aop="http://www.springframework.org/schema/aop"
     xsi:schemaLocation="http://www.springframework.org/schema/beans
         http://www.springframework.org/schema/beans/spring-beans.xsd
         http://www.springframework.org/schema/context
         http://www.springframework.org/schema/context/spring-context.xsd
         http://www.springframework.org/schema/aop
         http://www.springframework.org/schema/aop/spring-aop.xsd">

     <context:annotation-config></context:annotation-config>
     <context:component-scan base-package="com.dzg.spring"></context:component-scan>
     <aop:aspectj-autoproxy></aop:aspectj-autoproxy>
     <!-- <bean id="userDAO" class="com.dzg.spring.dao.impl.UserDAOImpl"></bean>
         <bean id="logInterceptor" class="com.dzg.spring.aop.LogInterceptor"></bean>
         <bean id="userService" class="com.dzg.spring.service.UserService"> <property
         name="UserDAO" ref="userDAO" /> </bean> -->
 </beans>

beans.xml

测试代码（使用的是junit测试）

 package com.dzg.spring.service;

 import org.junit.Test;
 import org.springframework.context.support.ClassPathXmlApplicationContext;

 import com.dzg.spring.model.User;

 public class UserServiceTest {

     @Test
     public void testAdd() throws Exception {
         ClassPathXmlApplicationContext ctx = new ClassPathXmlApplicationContext("beans.xml");

         UserService service = (UserService) ctx.getBean("userService");
         System.out.println(service.getClass());
         User u = new User();
         u.setUsername("zhangsan");
         u.setPassword("zhangsan");
         service.add(u);
         ctx.close();
     }

 }

UserServiceTest.java

控制台输出：

class com.dzg.spring.service.UserService$$EnhancerBySpringCGLIB$$21c652e7
Method Around Start!
Method start!
user saved!
Method Around Complete!
Method Complete!