AOP面向切面编程思想:横向重复代码,纵向抽取
动态代理:1.通过动态代理可以提现 aop思想
2.对目标对象中的方法进行增强
Spring Aop开发:Spring 封装了动态代理代码,不需要手动写代理代码,并且还封装了cglib代理
1、xml配置
1.1 导包
springsource.org.aopalliance-1.0.0.jar
springsource.org.apache.commons.logging-1.1.1.jar
springsource.org.apache.log4j-1.2.15.jar
springsource.org.aspectj.weaver-1.6.8.RELEASE.jar
spring-aop-4.2.4.RELEASE.jar
spring-aspects-4.2.4.RELEASE.jar
spring-beans-4.2.4.RELEASE.jar
spring-context-4.2.4.RELEASE.jar
spring-core-4.2.4.RELEASE.jar
spring-expression-4.2.4.RELEASE.jar
spring-test-4.2.4.RELEASE.jar
1.2 准备目标对象
UserService接口
package com.hciot.service; public interface UserService { void save(); void delete(); void update(); void find(); }UserSeviceImpl实现UseService接口
package com.hciot.service; public class UserServiceImpl implements UserService { @Override public void save() { System.out.println("保存用户"); } @Override public void delete() { System.out.println("删除用户"); } @Override public void update() { System.out.println("更新用户"); } @Override public void find() { System.out.println("查找用户"); } }
1.3 准备通知
通知类型:
a.前置通知—目标方法运行之前调用
b.后置通知(出现异常不会调用)—目标方法运行之后调用
c.环绕通知—目标方法运行之前和运行之后都调用
d. 异常拦截通知—如果出现异常就会调用
e.后置通知(无论是否出现异常都会调用)—目标方法运行之后调用
package com.hciot.d_springaop; import org.aspectj.lang.ProceedingJoinPoint; public class MyAdvice { public void before(){ System.out.println("这是前置通知"); } public void afterReturning(){ System.out.println("这是后置通知(出现异常不会调用)"); } public Object around(ProceedingJoinPoint pjp) throws Throwable{ System.out.println("这是环绕通知之前部分"); Object proceed = pjp.proceed(); System.out.println("这是环绕通知之后部分"); return proceed; } public void afterException(){ System.out.println("出现异常"); } public void after(){ System.out.println("这是后置通知,出现异常也会调用"); } }
1.4 配置进行织入,将通知织入目标对象中
<?xml version="1.0" encoding="UTF-8"?> <beans xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://www.springframework.org/schema/beans" xmlns:aop="http://www.springframework.org/schema/aop" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans-4.2.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop-4.2.xsd "> <!--准备工作:导入aop命名空间 --> <!-- 1.配置目标对象 --> <bean name="userService" class="com.hciot.service.UserServiceImpl"></bean> <!-- 2.配置通知对象 --> <bean name="myAdvice" class="com.hciot.d_springaop.MyAdvice"></bean> <!-- 3.配置将通知织入目标对象 --> <aop:config> <!-- 1.配置切入点 public void com.hciot.service.UserServiceImp.save() void com.hciot.service.UserServiceImp.save() * com.hciot.service.UserServiceImp.save() * com.hciot.service.UserServiceImp.*() * com.hciot.service.UserServiceImp.*(..) * com.hciot.service.*ServiceImp.*(..) --> <aop:pointcut expression="execution(* com.hciot.service.*ServiceImpl.*(..))" id="pc"/> <aop:aspect ref="myAdvice"> <!-- 指定名为before方法作为前置 通知--> <aop:before method="before" pointcut-ref="pc"/> <!-- 后置 --> <aop:after-returning method="afterReturning" pointcut-ref="pc"/> <!-- 环绕 通知--> <aop:around method="around" pointcut-ref="pc"/> <!-- 异常拦截通知--> <aop:after-throwing method="afterException" pointcut-ref="pc"/> <!-- 后置--> <aop:after method="after" pointcut-ref="pc"/> </aop:aspect> </aop:config> </beans>1.5 测试代码
package com.hciot.d_springaop; import javax.annotation.Resource; import org.junit.Test; import org.junit.runner.RunWith; import org.springframework.test.context.ContextConfiguration; import org.springframework.test.context.junit4.SpringJUnit4ClassRunner; import com.hciot.service.UserService;
@RunWith(SpringJUnit4ClassRunner.class) //帮我们创建容器 @ContextConfiguration("classpath:com/hciot/d_springaop/applicationContext.xml")
public class Demo { @Resource(name="userService") private UserService us; @Test public void fun(){ us.save(); } }2、注解配置
package com.hciot.e_annotationaop; import org.aspectj.lang.ProceedingJoinPoint; import org.aspectj.lang.annotation.After; import org.aspectj.lang.annotation.AfterReturning; import org.aspectj.lang.annotation.AfterThrowing; import org.aspectj.lang.annotation.Around; import org.aspectj.lang.annotation.Aspect; import org.aspectj.lang.annotation.Before; import org.aspectj.lang.annotation.Pointcut; @Aspect //表示该类是通知类 public class MyAdvice { @Pointcut("execution(* com.hciot.service.*ServiceImpl.*(..))") public void pc(){} //指定该方法是前置通知,并指定切入点 @Before("MyAdvice.pc()") public void before(){ System.out.println("这是前置通知"); } @AfterReturning("MyAdvice.pc()") public void afterReturning(){ System.out.println("这是后置通知(出现异常不会调用)"); } @Around("MyAdvice.pc()") public Object around(ProceedingJoinPoint pjp) throws Throwable{ System.out.println("这是环绕通知之前部分"); Object proceed = pjp.proceed(); System.out.println("这是环绕通知之后部分"); return proceed; } @AfterThrowing("MyAdvice.pc()") public void afterException(){ System.out.println("出现异常"); } @After("MyAdvice.pc()") public void after(){ System.out.println("这是后置通知,出现异常也会调用"); } }