spring4中文技術(shù)手冊

spring4spring4中文技術(shù)手冊在《靜態(tài)代理和動態(tài)代理》中提到了面對方面編程，主要就是基于動態(tài)代理。單獨抽象出非業(yè)務(wù)的功能，效勞于某些業(yè)務(wù)方法。SpringAdvice，分別為：BeforeAdvice,AfterReturningAdvice,AroundAdvice,AfterthrowingAdvice。都是方法級別的，就是在某個方法執(zhí)行前后插入一些非業(yè)務(wù)的操作，如打日志或者推斷權(quán)限等。advice的實現(xiàn)，springxmlannotation(注釋)。BeforeAdviceAfterAdviceAroundAdvice則可以在目標(biāo)方法執(zhí)行前后同時加上相關(guān)效勞；ThrowAdvice是在特別發(fā)生后執(zhí)行某些操作。1.AdviceAspectSpring接口。BeforeAdviceorg.springframework.aop.MethodBeforeAdvice接口：1. 1. /**2.*Adviceinvokedbeforeamethodisinvoked.Suchadvicescannot3.*preventthemethodcallproceeding,unlesstheythrowaThrowable.4.*/5. publicinterfaceMethodBeforeAdviceextendsBeforeAdvice{6.7./**8.*Callbackbeforeagivenmethodisinvoked.9.*@parammethodmethodbeinginvoked10.*@paramargsargumentstothemethod11.*@paramtargettargetofthemethodinvocation.Maybe<code>null</code>.12.*@throwsThrowableifthisobjectwishestoabortthecall.13.*Anyexceptionthrownwillbereturnedtothecallerifit”s14.*allowedbythemethodsignature.Otherwisetheexception15.*willbewrappedasaruntimeexception.16.*/17.voidbefore(Methodmethod,Object[]args,Objecttarget)throwsThrowable;18.}AfterAfterAdviceorg.springframework.aop.AfterReturningAdvice接口：1. /**2.2.*Afterreturningadviceisinvokedonlyonnormalmethodreturn,notifan3.*exceptionisthrown.Suchadvicecanseethereturnvalue,butcannotchangeit.4.*/5. publicinterfaceAfterReturningAdviceextendsAfterAdvice{6./**7.*Callbackafteragivenmethodsuccessfullyreturned.8.*@paramreturnValuethevaluereturnedbythemethod,ifany9.*@parammethodmethodbeinginvoked10.*@paramargsargumentstothemethod11.*@paramtargettargetofthemethodinvocation.Maybe<code>null</code>.12.*@throwsThrowableifthisobjectwishestoabortthecall.13.*Anyexceptionthrownwillbereturnedtothecallerifit”s14.*allowedbythemethodsignature.Otherwisetheexception15.*willbewrappedasaruntimeexception.16.*/17.voidafterReturning(ObjectreturnValue,Methodmethod,Object[]args,Objecttarget)throwsThrowable;18.}AroundAroundAercept.MethodInterceptor接口：1. /**2.*<p>Theusershouldimplementthe{@link#invoke(MethodInvocation)}3.*methodtomodifytheoriginalbehavior.E.g.thefollowingclass4.*implementsatracinginterceptor(tracesallthecallsonthe5.*interceptedmethod(s)):6.*7.*<preclass=code>8.*classTracingInterceptorimplementsMethodInterceptor{9.* Objectinvoke(MethodInvocationi)throwsThrowable{10. *System.out.println(“method“+i.getMethod+“iscalledon“+11. *i.getThis+“withargs“+i.getArguments);12. *Objectret=ceed;13. *System.out.println(“method“+i.getMethod+“returns“+ret);14. *returnret;15. 15. * }16. *}17. *</pre>*/18.publicinterfaceMethodInterceptorextendsInterceptor{19.20./**21.*Implementthismethodtoperformextratreatmentsbeforeand22.*aftertheinvocation.Politeimplementationswouldcertainly23.*liketoinvoke{@linkJoinpoint#proceed}.24.*25.*@paraminvocationthemethodinvocationjoinpoint26.*@returntheresultofthecallto{@link27.*Joinpoint#proceed},mightbeinterceptedbythe28.*interceptor.29.*30.*@throwsThrowableiftheinterceptorsorthe31.*target-objectthrowsanexception.*/32.Objectinvoke(MethodInvocationinvocation)throwsThrowable;33.}類前面的注釋說明白該方法的使用，就是要在類前面的注釋說明白該方法的使用，就是要在invoke方法中調(diào)用MethodIceed，將執(zhí)行傳給下一個Interceptor，最終執(zhí)行目標(biāo)方法。在proceed方法前后加操作，到達(dá)Aroudadvice的作用。Aspectbeanorg.springframework.aop.framework.ProxyFactoryBeanAspect。如下：1. <beanid=“helloProxy“class=“org.springframework.aop.framework.ProxyFactoryBean“>2.業(yè)務(wù)接口-->3.<propertyname=“proxyInterfaces“value=“spring.advice.IHello“/>4.實現(xiàn)該接口的目標(biāo)類-->5.<propertyname=“target“ref=“helloSpeaker“/>6.Aspect7.<propertyname=“interceptorNames“>8.<list>9.<value>throwAdvice</value>10.還可以連續(xù)加,如11.<value>logBeforeAdvice</value>-->12.12.</list>13.</property>14.</bean>補充下，其中的目標(biāo)類、解釋器(Aspect)Bean定義文件中先進(jìn)展定義，然后才可以引用的。我們使用時，代碼如下：IHelloIHellohelloProxy=(IHello)context.getBean(“helloProxy“);helloProxy.hello;BeanBeanAspectjoinPoint應(yīng)用到目標(biāo)方法上。補：IHellohello方法，HelloSpeakerIHello接口。hello方法前后參與日志記錄。1. publicclassAroundAdviceimplementsMethodInterceptor{2.privateLoggerlogger=3.4.@Override5.publicObjectinvoke(MethodInvocationmethodInvocation)throwsThrowable{6.7.logger.log(Level.INFO,“methodstarts...“+methodInvocation.getMethod);8.result=methodIceed;9.ends...“+methodInvocation.getMethod);10.11.returnresult;12.}13.}配置：<?xml<?xmlversion=“1.0“encoding=“UTF-8“?>3.4.>5.<beanid=“helloSpeaker“class=“spring.advice.HelloSpeaker“/>IHelloIHellohelloProxy=(IHello)context.getBean(“helloProxy“);helloProxy.hello(“前后加日志“);就會消滅如下結(jié)果：6.<beanid=“aroundAdvice“class=“spring.advice.AroundAdvice“/>7.8.<beanid=“helloProxy“class=“org.springframework.aop.framework.ProxyFact