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>

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;
    }
}

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;
    }

}

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);
}

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!");
    }

}

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!");
    }

}

 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>

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();
    }

}

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!