Spring AOP的概念与实现过程详解

<!-- https://mvnrepository测试数据/artifact/org.aspectj/aspectjweaver -->

< dependency >

   < groupId >org.aspectj</ groupId >

   < artifactId >aspectjweaver</ artifactId >

   < version >1.9.7</ version >

   < scope >runtime</ scope >

</ dependency >

<? xml version = "1.0" encoding = "UTF-8" ?>

< beans xmlns = "http://HdhCmsTestspringframework.org/schema/beans"

        xmlns:xsi = "http://HdhCmsTestw3.org/2001/XMLSchema-instance"

xmlns:aop = "http://HdhCmsTestspringframework.org/schema/aop"

xsi:schemaLocation = "http://HdhCmsTestspringframework.org/schema/beans      https://HdhCmsTestspringframework.org/schema/beans/spring-beans.xsd                     http://HdhCmsTestspringframework.org/schema/aop                  https://HdhCmsTestspringframework.org/schema/aop/spring-aop.xsd" >

   < bean id = "userServiceImpl" class = "com.mount.service.UserServiceImpl" />

   < bean id = "log" class = "com.mount.log.log" />

   < bean id = "afterLog" class = "com.mount.log.AfterLog" />

   <!--  配置AOP  -->

   < aop:config >

     <!-- 切入点 expression表达式  表示从哪里开始执行   -->

     < aop:pointcut id = "pointcut" expression = "execution(* com.mount.service.UserServiceImpl.*(..))" />

     <!--      执行环绕增强  -->

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

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

   </ aop:config >

</ beans >

// 执行前  实现spring内置接口MethodBeforeAdvice

public class log implements MethodBeforeAdvice {

     public void before(Method method, Object[] args, Object target) throws Throwable {

         System.out.println(target.getClass().getName()+ "执行了" +method.getName()+ "方法" );

     }

}

// 执行后 实现AfterReturningAdvice

public class AfterLog implements AfterReturningAdvice {

   public void afterReturning(Object returnValue, Method method, Object[] args, Object target) throws Throwable {

     System.out.println(target.getClass().getName()+ "调用了" +method.getName()+ "方法" + "返回的结果为" +returnValue);

   }

}

@Test

public void test01(){

   ApplicationContext context = new ClassPathXmlApplicationContext( "applicationContext.xml" );

   UserService bean = context.getBean( "userServiceImpl" , UserService. class );

   bean.insert();

}

<!--  配置AOP 方式二  -->

< bean id = "diy" class = "com.mount.diyLog.diyLogImpl" />

< aop:config >

   <!--     自定义切面 ref引入的类   -->

   < aop:aspect ref = "diy" >

     < aop:pointcut id = "pointcut" expression = "execution(* com.mount.service.UserServiceImpl.*(..))" />

     < aop:before method = "before" pointcut-ref = "pointcut" />

     < aop:after method = "after" pointcut-ref = "pointcut" />

   </ aop:aspect >

</ aop:config >

public class diyLog {

   public void before(){

     System.out.println( "===before方法执行===" );

   }

   public void after(){

     System.out.println( "===after方法执行===" );

   }

}

<!-- SpringAop开启注解支持 -->

< aop:aspectj-autoproxy />

<!-- 映射自定义注解实现log类 -->

< bean id = "annoLog" class = "com.mount.annoLog.annoLogImpl" />

// Aspect标注该类是一个切面

@Aspect

public class annoLogImpl {

   // 前置增强

   @Before ( "execution(* com.mount.service.UserServiceImpl.*(..))" )

   public void before(){

     System.out.println( "---方法执行前---" );

   }

   // 后置增强

   @After ( "execution(* com.mount.service.UserServiceImpl.*(..))" )

   public void after(){

     System.out.println( "---方法执行后---" );

   }

   // 环绕增强

   @Around ( "execution(* com.yuqu.dao.UserMapperImpl.*(..))" )

     public Object around(ProceedingJoinPoint pjp) throws Throwable {

         System.out.println( "环绕前" );

         Object proceed = pjp.proceed();

         System.out.println( "环绕后" );

         System.out.println( "执行信息：" +pjp.getSignature());

         return proceed;

     }

}