SSM-Spring-11：Spring中使用代理工厂Bean实现aop的四种增强
------------吾亦无他,唯手熟尔，谦卑若愚，好学若饥-------------
说说那四种增强：前置增强，后置增强，环绕增强，异常增强
那什么是代理工厂bean呢？
org.springframework.aop.framework.ProxyFactoryBean
就是这个东西，他可以实现对方法的增强
@No.1:前置增强：
需要前置增强的类SomeServiceImpl
package cn.dawn.day11aop01; /** * Created by Dawn on 2018/3/8. */ public class SomeServiceImpl { public void doSome() { System.out.println("do something"); } }
前置增强的内容的类，可以说实现前置增强接口的类LoggerBefore
package cn.dawn.day11aop01; import org.springframework.aop.MethodBeforeAdvice; import java.lang.reflect.Method; /** * Created by Dawn on 2018/3/5. */ /*前置增强*/ public class LoggerBefore implements MethodBeforeAdvice { public void before(Method method, Object[] objects, Object o) throws Throwable { System.out.println("日志记录"); } }
配置文件中：
<?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" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" 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 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!--要增强的对象--> <bean id="service" class="cn.dawn.day11aop01.SomeServiceImpl"></bean> <!--增强的内容--> <bean id="before" class="cn.dawn.day11aop01.LoggerBefore"></bean> <!--代理工厂bean--> <bean id="proxyfactory" class="org.springframework.aop.framework.ProxyFactoryBean"> <!--要增强的对象--> <property name="target" ref="service"></property> <!--增强的内容--> <property name="interceptorNames" value="before"></property> </bean> </beans>
单测方法：
package cn.dawn.day11aop01; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; /** * Created by Dawn on 2018/3/3. */ public class test20180305 { @Test /*aop代理工厂bean前置增强*/ public void t01(){ ApplicationContext context=new ClassPathXmlApplicationContext("ApplicationContext-day11aop01.xml"); SomeServiceImpl service = (SomeServiceImpl) context.getBean("proxyfactory"); service.doSome(); } }
@No.2:后置增强：
需要后置增强的类：SomeServiceImpl（此类和前置那个写在不同包下，一会的配置文件也不同，往后都是如此）
package cn.dawn.day12aop02; /** * Created by Dawn on 2018/3/8. */ public class SomeServiceImpl { public void doSome() { System.out.println("do something"); } }
后置增强的内容的的类，他与前置增强的那个实现的接口不同：LoggerAfter
package cn.dawn.day12aop02; import org.springframework.aop.AfterReturningAdvice; import java.lang.reflect.Method; /** * Created by Dawn on 2018/3/5. */ /*后置增强*/ public class LoggerAfter implements AfterReturningAdvice { public void afterReturning(Object o, Method method, Object[] objects, Object o1) throws Throwable { System.out.println("===============after=================="); } }
配置文件中：
<?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" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" 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 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!--要增强的对象--> <bean id="service" class="cn.dawn.day12aop02.SomeServiceImpl"></bean> <!--增强的内容--> <bean id="afteradvice" class="cn.dawn.day12aop02.LoggerAfter"></bean> <!--代理工厂bean--> <bean id="proxyfactory" class="org.springframework.aop.framework.ProxyFactoryBean"> <!--要增强的对象--> <property name="target" ref="service"></property> <!--增强的内容--> <property name="interceptorNames" value="afteradvice"></property> </bean> </beans>
单测方法：
package cn.dawn.day12aop02; import cn.dawn.day12aop02.SomeServiceImpl; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; /** * Created by Dawn on 2018/3/3. */ public class test20180305 { @Test /*aop代理工厂bean后置增强*/ public void t01(){ ApplicationContext context=new ClassPathXmlApplicationContext("ApplicationContext-day12aop02.xml"); SomeServiceImpl service = (SomeServiceImpl) context.getBean("proxyfactory"); service.doSome(); } }
@No.3:环绕增强：
需要环绕增强的类：SomeServiceImpl
package cn.dawn.day13aop03; /** * Created by Dawn on 2018/3/8. */ public class SomeServiceImpl { public void doSome() { System.out.println("do something"); } }
环绕增强内容的：
package cn.dawn.day13aop03; import org.aopalliance.intercept.MethodInterceptor; import org.aopalliance.intercept.MethodInvocation; /** * Created by Dawn on 2018/3/8. */ /*环绕增强需要实现MethodInterceptor这个接口*/ public class MethodAdvice implements MethodInterceptor { public Object invoke(MethodInvocation methodInvocation) throws Throwable { System.out.println("前置增强"); /*它可以使前置增强和后置增强分开，同时实现前置和后置*/ methodInvocation.proceed(); System.out.println("后置增强"); return null; } }
配置文件：
<?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" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" 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 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!--要增强的对象--> <bean id="service" class="cn.dawn.day13aop03.SomeServiceImpl"></bean> <!--增强的内容--> <bean id="methodAdvice" class="cn.dawn.day13aop03.MethodAdvice"></bean> <!--代理工厂bean--> <bean id="proxyfactory" class="org.springframework.aop.framework.ProxyFactoryBean"> <!--要增强的对象--> <property name="target" ref="service"></property> <!--增强的内容--> <property name="interceptorNames" value="methodAdvice"></property> </bean> </beans>
单测方法：
<?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" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" 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 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!--要增强的对象--> <bean id="service" class="cn.dawn.day13aop03.SomeServiceImpl"></bean> <!--增强的内容--> <bean id="methodAdvice" class="cn.dawn.day13aop03.MethodAdvice"></bean> <!--代理工厂bean--> <bean id="proxyfactory" class="org.springframework.aop.framework.ProxyFactoryBean"> <!--要增强的对象--> <property name="target" ref="service"></property> <!--增强的内容--> <property name="interceptorNames" value="methodAdvice"></property> </bean> </beans>
@No.4:异常增强：
异常增强是主要用在他出错的时候，进行记录用的，此处模拟起来简单的就是除0异常和空指针异常
写一个类，它里面的方法存在异常，运行时异常
SomeServiceImpl类
package cn.dawn.day14aop04; /** * Created by Dawn on 2018/3/8. */ public class SomeServiceImpl { public void doSome() { System.out.println("do something"); String abc=null; System.out.println(abc.toString());; } }
此处模拟的是空指针异常，当然异常种类很多，不一一模拟了
实现ThrowsAdvice接口的类
package cn.dawn.day14aop04; import org.springframework.aop.ThrowsAdvice; /** * Created by Dawn on 2018/3/8. */ public class MyThrowsAdvice implements ThrowsAdvice { public void afterThrowing(Exception ex){ System.out.println("网络中断XXXXX-错误号05289"); } }
他这个接口里面没有方法要重写，很是奇怪，那是随便写什么defgabc的都可以吗？不是的，翻他的源码，他在上面的注释里提供了模板，只有按照他模板写的才能读取到，此处我用了他的其中一个模板方法
配置文件中：
<?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" xmlns:p="http://www.springframework.org/schema/p" xmlns:context="http://www.springframework.org/schema/context" 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 http://www.springframework.org/schema/context http://www.springframework.org/schema/context/spring-context.xsd"> <!--要增强的对象--> <bean id="service" class="cn.dawn.day14aop04.SomeServiceImpl"></bean> <!--增强的内容--> <bean id="myThrowsAdvice" class="cn.dawn.day14aop04.MyThrowsAdvice"></bean> <!--代理工厂bean--> <bean id="proxyfactory" class="org.springframework.aop.framework.ProxyFactoryBean"> <!--要增强的对象--> <property name="target" ref="service"></property> <!--增强的内容--> <property name="interceptorNames" value="myThrowsAdvice"></property> </bean> </beans>
单测方法：
package cn.dawn.day14aop04; import cn.dawn.day14aop04.SomeServiceImpl; import org.junit.Test; import org.springframework.context.ApplicationContext; import org.springframework.context.support.ClassPathXmlApplicationContext; /** * Created by Dawn on 2018/3/3. */ public class test20180305 { @Test /*aop代理工厂bean异常增强*/ public void t01(){ ApplicationContext context=new ClassPathXmlApplicationContext("ApplicationContext-day14aop04.xml"); SomeServiceImpl service = (SomeServiceImpl) context.getBean("proxyfactory"); try{ service.doSome(); }catch (Exception ex){ ex.printStackTrace(); } } }
看到这儿的try-catch了吧，他的作用是让单测能通过单元测试，能变成对勾，能执行到结束，不会因为模拟的异常而中断
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基于代理工厂Bean实现aop的四种增强总结完毕
