Spring4面向切面AOP
阿新 • • 發佈：2019-02-05
面向切面程式設計(也叫面向方面程式設計)：Aspect Oriented Programming(AOP)，是軟體開發中的一個熱點，也是Spring
框架中的一個重要內容。利用AOP 可以對業務邏輯的各個部分進行隔離，從而使得業務邏輯各部分之間的耦合度降低，提高程式的可重用性，同時提高了開發的效率。
主要的功能是：日誌記錄，效能統計，安全控制，事務處理，異常處理等等。
1，前置通知；
2，後置通知；
3，環繞通知；
4，返回通知；
5，異常通知；
寫一個service介面和 serviceImpl實現類
【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" xsi:schemaLocation="http://www.springframework.org/schema/beans http://www.springframework.org/schema/beans/spring-beans.xsd"> <!-- 父類引用指向子類例項 --> <bean id="employeeService" class="com.zhiqi.service.impl.EmployeeServiceImpl"> </bean> </beans>
【介面】
package com.zhiqi.service;
public interface EmployeeService {
public void doSomething();
}【實現類】
package com.zhiqi.service.impl; import com.zhiqi.service.EmployeeService; public class EmployeeServiceImpl implements EmployeeService { @Override public void doSomething() { // TODO Auto-generated method stub System.out.println("準備工作"); System.out.println("業務邏輯實現"); System.out.println("收尾工作"); } }
【測試】
package com.zhiqi.test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; import com.zhiqi.service.EmployeeService; public class MyTest { public static void main(String[] args) { ApplicationContext ac=new ClassPathXmlApplicationContext("beans.xml"); EmployeeService employeeService=(EmployeeService) ac.getBean("employeeService"); employeeService.doSomething(); } }
執行：
Spring提供了很好的解耦合機制
首先引入jar包：
然後從官方xml配置複製一下配置資訊：
即是：
<?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
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd">
</beans>然後定義前置通知
package com.zhiqi.advice;
import org.aspectj.lang.JoinPoint;
public class EmployeeServiceAspect {
//前置通知
public void doBefore(JoinPoint jp){
System.out.println("準備工作");
}
}
<?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
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd">
<bean id="employeeServiceAspect" class="com.zhiqi.advice.EmployeeServiceAspect"></bean>
<!-- 父類引用指向子類例項 -->
<bean id="employeeService" class="com.zhiqi.service.impl.EmployeeServiceImpl">
</bean>
<aop:config>
<aop:aspect id="employeeServiceAspect" ref="employeeServiceAspect">
<aop:pointcut expression="execution(* com.zhiqi.service.*.*(..))" id="businessService"/>
<aop:before method="doBefore" pointcut-ref="businessService"/>
</aop:aspect>
</aop:config>
</beans>執行如圖：
前置、後置、環繞、返回、異常----配置示例
<?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
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
http://www.springframework.org/schema/aop/spring-aop.xsd">
<bean id="employeeServiceAspect" class="com.zhiqi.advice.EmployeeServiceAspect"></bean>
<!-- 父類引用指向子類例項 -->
<bean id="employeeService" class="com.zhiqi.service.impl.EmployeeServiceImpl">
</bean>
<aop:config>
<aop:aspect id="employeeServiceAspect" ref="employeeServiceAspect">
<aop:pointcut expression="execution(* com.zhiqi.service.*.*(..))" id="businessService"/>
<!--aop:before method="doBefore" pointcut-ref="businessService"/>
<aop:after method="doAfter" pointcut-ref="businessService"/-->
<aop:around method="doAround" pointcut-ref="businessService"/>
<aop:after-returning method="doAfterReturning" pointcut-ref="businessService"/>
<aop:after-throwing method="doAfterThrowing" pointcut-ref="businessService" throwing="ex"/>
</aop:aspect>
</aop:config>
</beans>package com.zhiqi.advice;
import org.aspectj.lang.JoinPoint;
import org.aspectj.lang.ProceedingJoinPoint;
public class EmployeeServiceAspect {
// //前置通知
// public void doBefore(JoinPoint jp){
// System.out.println("類名："+jp.getTarget().getClass().getName());
// System.out.println("準備工作："+" "+jp.getArgs()[0]);
// }
// //後置通知
// public void doAfter(JoinPoint jp){
// System.out.println("類名："+jp.getTarget().getClass().getName());
// System.out.println("收尾工作："+" "+jp.getArgs()[0]);
// }
//環繞通知
public Object doAround(ProceedingJoinPoint pjp) throws Throwable{
System.out.println("環繞通知-前");
Object retValue=pjp.proceed();
System.out.println("環繞通知-後");
return retValue;
}
//返回通知
public void doAfterReturning(JoinPoint jp){
System.out.println("返回通知");
}
public void doAfterThrowing(JoinPoint jp,Throwable ex){
System.out.println("異常通知"+" "+"異常資訊-"+ex.getMessage());
}
}