AOP

 XML配置

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


    <bean id="userService" class="com.ljm.service.UserService_"/>
    <bean id="log" class="com.ljm.log.Log"/>
    <bean id="afterLog" class="com.ljm.log.Afterlog"/>

    <aop:config>


        <aop:pointcut id="pointcut" expression="execution(* com.ljm.service.UserService_.*(..))"/>
        <aop:pointcut id="pointcut1" expression="execution(* com.ljm.service.UserService_.add(..))"/>

        <aop:advisor advice-ref="log" pointcut-ref="pointcut"/>
        <aop:advisor advice-ref="afterLog" pointcut-ref="pointcut1"/>

    aop:config>


beans>

接口(略)

实现类(略)

前置

public class Log implements MethodBeforeAdvice {
    @Override
    //method  需要执行目标对象的方法
    //objects  相关参数  ==args
    //o         目标对象  ==target
    //自动调用
    public void before(Method method, Object[] objects, Object o) throws Throwable {
        System.out.println("前置 "+o.getClass().getName()+" 的 "+method.getName()+" 方法正在运行 ");
    }
}

后置

public class Afterlog implements AfterReturningAdvice {
    @Override
    //returenValue  返回值
    //method  需要执行目标对象的方法
    //objects  相关参数  ==args
    //o         目标对象  ==target
    public void afterReturning(Object returenValue, Method method, Object[] objects, Object o1) throws Throwable {
        System.out.println(" after 执行了"+method.getName()+"方法   返回的结果为"+returenValue);
    }
}

测试

    public static void main(String[] args) {
        ApplicationContext context = new ClassPathXmlApplicationContext("applicationContext.xml");
        //动态代理的是接口  UserService是接口
        UserService userService = (UserService)context.getBean("userService");
        userService.add();
        userService.delete();
    }

方法2:自定义类(视频推荐)

相对简单,但功能有限

public class DiyPointCut {
    public void before(){
        System.out.println("=====前面执行===");
    }
    public void after(){
        System.out.println("=====后面执行===");
    }
}

XML相关

    <bean id="diy" class="com.ljm.diy.DiyPointCut"/>
    <aop:config>


        <aop:aspect ref="diy">

            <aop:pointcut id="point" expression="execution(* com.ljm.service.UserService_.*(..))"/>

            <aop:before method="before" pointcut-ref="point"/>
            <aop:after method="after" pointcut-ref="point"/>
        aop:aspect>
    aop:config>

方法3:使用注解实现(调试代码不变)

在pom中导入依赖

   <dependency>
            <groupId>org.aspectjgroupId>
            <artifactId>aspectjweaverartifactId>
            <version>1.9.4version>
            <scope>runtimescope>
        dependency>
        <dependency>
            <groupId>org.aspectjgroupId>
            <artifactId>aspectjrtartifactId>
            <version>1.9.4version>
        dependency>

自定义相关类

@Aspect
public class AnotationPointCut {

    @Before("execution(* com.ljm.service.UserService_.*(..))")
    public void before(){
        System.out.println("方法执行前-注解实现,Before");
    }
    @After("execution(* com.ljm.service.UserService_.*(..))")
    public void after(){
        System.out.println("方法执行后-注解实现,After");
    }
    //在环绕增强中,可以给个参数,代表获取处理的点
    @Around("execution(* com.ljm.service.UserService_.*(..))")
    public  void around(ProceedingJoinPoint jp){
        System.out.println("环绕前");
//        jp.getSignature();
        System.out.println("签名=执行方法="+jp.getSignature());
        try {
            Object proceed = jp.proceed();  //执行方法
        } catch (Throwable throwable) {
            throwable.printStackTrace();
        }
        System.out.println("环绕后");
    }
}

配置XML中

    <bean id="diy01" class="com.ljm.diy.AnotationPointCut"/>

    <aop:aspectj-autoproxy proxy-target-class="false"/>

 执行顺序