springAOP-xml中声明切面

末蓝、 2021-10-19 22:50 464阅读 0赞

1 spring的aop命名空间中,提供了多个元素用来在XML中声明切面,如下所示:

====================================================================================================
    	aop配置元素                         用途
    	<aop:advisor>                       定义AOP通知器
    	<aop:after>                         定义AOP后置通知(不管被通知的方法是否执行成功)
    	<aop:after-returning>               定义aop返回通知
    	<aop:after-throwing>                定义aop异常通知
    	<aop:around>                        定义aop环绕通知
    	<aop:aspect>                        定义一个切面
    	<aop:aspectj-autoproxy>             启用@Aspect注解驱动的切面
    	<aop:before>                        定义一个AOP前置通知
    	<aop:config>                        顶层的AOP配置元素.大多数的<aop:*>元素必须包含在<aop:config>元素内.
    	<aop:declare-parents>               以透明的方式为被通知的对象引入额外的接口
    	<aop:pointcut>                      定义一个切点
    	=====================================================================================================

2 切面目标对象

package com.musi.bean;
    import org.springframework.stereotype.Component;
    @Component
    public class Animal {
    
        public void run(){
            System.out.println("animal is running .....");
        }
    
        public void run(String  name){
            System.out.println(name+" is running ........");
        }
    
        public void run(int times){
            System.out.println("animal running times:"+times);
        }
    }

3 切面

package com.musi.aop.xmlaspect;
    
    import org.springframework.stereotype.Component;
    
    @Component
    public class AnimalXmlAspect {
    
        public void beforeRunning(){
            System.out.println("Xml before running .......");
        }
    
        public void afterRunning(){
            System.out.println("Xml after running .......");
        }
    
        public void afterReturning(){
            System.out.println("Xml afterReturning running .......");
        }
    
        public void afterThrowing(){
            System.out.println("Xml afterThrowing running .......");
        }
    }

4 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:context="http://www.springframework.org/schema/context"
           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/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">
    
        <context:component-scan base-package="com.musi"/>
        
    
        <aop:config>
            <aop:aspect ref="animalXmlAspect">
                <aop:before pointcut="execution(* com.musi.bean.Animal.run(..))" method="beforeRunning"/>
                <aop:after pointcut="execution(* com.musi.bean.Animal.run(..))" method="afterRunning"/>
                <aop:after-returning pointcut="execution(* com.musi.bean.Animal.run(..))" method="afterReturning"/>
                <aop:after-throwing pointcut="execution(* com.musi.bean.Animal.run(..))" method="afterThrowing"/>
            </aop:aspect>
        </aop:config>
    
        <bean id="nimalXmlAspect" class="com.musi.aop.xmlaspect.AnimalXmlAspect" />
        <bean id="animalXmlRoundAspect" class="com.musi.aop.xmlaspect.AnimalXmlRoundAspect" />
        <bean id="animalXmlArgsAspect" class="com.musi.aop.xmlaspect.AnimalXmlArgsAspect" />
        <bean id="xmlEncoreable" class="com.musi.aop.xmlaspect.XmlEncoreableImpl" />
    </beans>

简化写法:

<aop:aspect ref="animalXmlAspect">
                <aop:pointcut id="run" expression="execution(* com.musi.bean.Animal.run(..))"/>
                <aop:before pointcut-ref="run" method="beforeRunning"/>
                <aop:after pointcut-ref="run" method="afterRunning"/>
                <aop:after-returning pointcut-ref="run" method="afterReturning"/>
                <aop:after-throwing pointcut-ref="run" method="afterThrowing"/>
            </aop:aspect>

说明:如果想在多个切面中使用同一个pointcut时,则将aop:pointcut元素放入aop:config中即可

5 声明环绕通知  
1)切面类

package com.musi.aop.xmlaspect;
    import org.aspectj.lang.ProceedingJoinPoint;
    public class AnimalXmlRoundAspect {
        public void aroundRunning(ProceedingJoinPoint pjp){
            try {
                System.out.println("xml around before ....");
                pjp.proceed();
                System.out.println("xml around after ....");
            }catch (Throwable throwable) {
                System.out.println("xml around trowing ....");
                throwable.printStackTrace();
            }
        }
    }

2)xml配置

<aop:aspect ref="animalXmlRoundAspect">
        <aop:pointcut id="run" expression="execution(* com.musi.bean.Animal.run(..))"/>
        <aop:around pointcut-ref="run" method="aroundRunning"/>
    </aop:aspect>

6 未通知传递参数  
1)切面类

package com.musi.aop.xmlaspect;
    
    public class AnimalXmlArgsAspect {
    
        public void beforeRunning(int times){
            System.out.println("xmlArgs before running times:"+times);
        }
    
        public void afterRunning(int times){
            System.out.println("xmlArgs after running times:"+times);
        }
    
        public void afterReturning(int times){
            System.out.println("xmlArgs afterReturning running times:"+times);
        }
    
        public void afterThrowing(int times){
            System.out.println("xmlArgs afterThrowing running times:"+times);
        }
    }

2)xml配置

<aop:aspect ref="animalXmlArgsAspect">
                <aop:pointcut id="run" expression="execution(* com.musi.bean.Animal.run(int)) and args(times)"/>
                <aop:before pointcut-ref="run" method="beforeRunning"/>
                <aop:after pointcut-ref="run" method="afterRunning"/>
                <aop:after-returning pointcut-ref="run" method="afterReturning"/>
                <aop:after-throwing pointcut-ref="run" method="afterThrowing"/>
            </aop:aspect>

7 通过切面引入新的功能  
1)声明一个接口

package com.musi.aop.xmlaspect;
    
    public interface XmlEncoreable {
        void jump();
    }

2)为接口添加一个实现类

package com.musi.aop.xmlaspect;
    public class XmlEncoreableImpl implements XmlEncoreable {
        public void jump() {
            System.out.println("this is XmlEncoreableImpl.....");
        }
    }

3)xml配置

<aop:aspect>
                <aop:declare-parents types-matching="com.musi.bean.Animal"
                                        implement-interface="com.musi.aop.xmlaspect.XmlEncoreable"
                                        delegate-ref="xmlEncoreable" />
            </aop:aspect>

8 测试类

package com.musi.test.bean;
    
    import com.musi.aop.xmlaspect.XmlEncoreable;
    import com.musi.bean.Animal;
    import org.junit.Test;
    import org.junit.runner.RunWith;
    import org.springframework.beans.factory.annotation.Autowired;
    import org.springframework.test.context.ContextConfiguration;
    import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
    
    @RunWith(SpringJUnit4ClassRunner.class)
    @ContextConfiguration({"classpath:application.xml"})
    public class SpringXmlTest {
        @Autowired
        private Animal animal;
    
        @Test
        public void test(){
            animal.run(1);
            XmlEncoreable xmlEncoreable = (XmlEncoreable)animal;
            xmlEncoreable.jump();
        }
    }