【Spring】AOP

添加Maven依赖：

    <!-- aspectj包的依赖 -->
    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjrt</artifactId>
      <version>1.9.1</version>
    </dependency>
    <!-- aspectjrtweaver包的依赖 -->
    <dependency>
      <groupId>org.aspectj</groupId>
      <artifactId>aspectjweaver</artifactId>
      <version>1.9.6</version>
    </dependency>

方法一：配置文件设置切面切点

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:context="http://www.springframework.org/schema/context"
       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">
    <!-- 注册bean -->
    <bean name="userDao" class="com.xiaobiti.dao.impl.UserDaoImpl"/>
    <bean name="xmlAdvice" class="com.xiaobiti.demo.xmlAdvice"/>
    <!-- 配置Spring AOP -->
    <aop:config>
        <!-- 指定切入点 -->
        <aop:pointcut id="pointcut" expression="execution(* com.xiaobiti.dao.impl.UserDaoImpl.*(..))"/>
        <!-- 指定切面 -->
        <aop:aspect ref="xmlAdvice">
            <!-- 前置通知 -->
            <aop:before method="before" pointcut-ref="pointcut"/>
            <!-- 返回通知 -->
            <aop:after-returning method="afterReturning" pointcut-ref="pointcut"/>
            <!-- 环绕通知 -->
            <aop:around method="around" pointcut-ref="pointcut"/>
            <!-- 异常通知 -->
            <aop:after-throwing method="afterException" pointcut-ref="pointcut"/>
            <!-- 后置通知 -->
            <aop:after method="after" pointcut-ref="pointcut"/>
        </aop:aspect>
    </aop:config>
</beans>

 UserDao.java

package com.xiaobiti.dao;

public interface UserDao {
    public boolean login(String username,String password);
    public void save();
    public void insert();
    public void delete();
    public void update();
    public void select();
}

UserDaoImpl.java

package com.xiaobiti.dao.impl;

import com.xiaobiti.dao.UserDao;
import com.xiaobiti.entity.User;
import org.springframework.stereotype.Repository;

import javax.annotation.Resource;

@Repository("userDao")
public class UserDaoImpl implements UserDao {
    @Resource(name = "user")
    private User user;
    @Override
    public boolean login(String username, String password) {
        if (username.equals("admin") && password.equals("1234")){
            return true;
        }
        return false;
    }

    @Override
    public void save() {
        System.out.println("执行dao中的方法");
        System.out.println(user);
    }

    @Override
    public void insert() {
        System.out.println("添加用户信息");
    }

    @Override
    public void delete() {
        System.out.println("删除用户信息");
    }

    @Override
    public void update() {
        System.out.println("修改用户信息");
    }

    @Override
    public void select() {
        System.out.println("查询用户信息");
    }
}

xmlAdvice.java

package com.xiaobiti.demo;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;

public class xmlAdvice {
    //前置通知
    public void before(JoinPoint joinpoint){
        System.out.println("这是前置通知...");
        System.out.println("目标类是："+joinpoint.getTarget());
        System.out.println(",被织入增强的目标的方法："+joinpoint.getSignature().getName());
    }
    //返回通知
    public void afterReturning(JoinPoint joinpoint){
        System.out.println("这是返回通知(不出现异常时候调用)...");
        System.out.println(",被织入增强的目标的方法："+joinpoint.getSignature().getName());
    }
    //环绕通知
    public Object around(ProceedingJoinPoint point) throws Throwable {
        System.out.println("这是环绕通知之前的部分...");
        //调用目标方法
        Object object = point.proceed();
        System.out.println("这是环绕通知之后的部分...");
        return object;
    }
    //异常通知
    public void afterException(JoinPoint joinpoint){
        System.out.println("这是异常通知...");
    }
    //后置通知
    public void after(JoinPoint joinpoint){
        System.out.println("这是后置通知...");
    }
}

运行测试代码：

public static void main(String[] args) {
        ApplicationContext  applicationContext = new ClassPathXmlApplicationContext("applicationContext.xml");
        UserDao userDao =  applicationContext.getBean("userDao",UserDao.class);
        userDao.delete();
        System.out.println("======================================");
        userDao.insert();
        System.out.println("======================================");
        userDao.update();
        System.out.println("======================================");
        userDao.select();
    }

运行结果：

方法二：注解自动配置

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:context="http://www.springframework.org/schema/context"
       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">
    <!--使用context命名空间，开启注解处理器-->
    <context:component-scan base-package="com.niuzhuang"/>
    <bean id="userDao" class="com.niuzhuang.dao.impl.UserDaoImpl"/>
    <bean id="xmlAdvice" class="com.niuzhuang.demo.XmlAdvice"/>
    <!--开启自动代理支持-->
    <aop:aspectj-autoproxy/>
</beans>

XmlAdvice.java

package com.niuzhuang.demo;

import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
import org.aspectj.lang.annotation.*;

@Aspect//切面
public class XmlAdvice {
    //切点
    @Pointcut("execution(* com.niuzhuang.dao.impl.UserDaoImpl.*(..))")
    public void poincut(){
    }
    //前置通知
    @Before("poincut()")
    public void before(JoinPoint joinPoint){
        System.out.println("这是前置通知....");
        System.out.println("目标类是："+joinPoint.getTarget()+",目标方法为："+joinPoint.getSignature().getName());
    }
    //返回通知
    @AfterReturning("poincut()")
    public void afterReturning(JoinPoint joinPoint){
        System.out.println("这是返回通知....");
        System.out.println("目标类是："+joinPoint.getTarget()+",目标方法为："+joinPoint.getSignature().getName());
    }
    //环绕通知
    @Around("poincut()")
    public Object around(ProceedingJoinPoint point) throws Throwable {
        System.out.println("这是返环绕通知之前....");
        //调用目标方法
       Object obj = point.proceed();
        System.out.println("这是返环绕通知之后....");
       return obj;
    }
    //异常通知
    @AfterThrowing("poincut()")
    public void afterException(JoinPoint joinPoint){
        System.out.println("这是异常通知....");
    }
    //后置通知
    @After("poincut()")
    public void after(JoinPoint joinPoint){
        System.out.println("这是后置通知....");
    }
}