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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:
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:
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:
单测方法:
@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:
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
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