Spring Framework Notes (23)--Configuring AOP based on configuration files

When we configure the IOC functionality, we implement the configuration file XML and annotations in two ways. There are two ways we can use it when implementing AOP functionality. Earlier, we described the implementation of AOP based on annotations, which I will use in the configuration file-based approach to the configuration of the original object bean, slice bean, tangent, and notification.

Declaring slices with an XML-based configuration

In addition to using AspectJ annotations to declare facets, Spring also supports declaring facets in a Bean configuration file. This declaration is done through the XML elements in the AOP schema.

Under normal circumstances, annotation-based declarations take precedence over XML-based declarations. With AspectJ annotations, facets can be compatible with AspectJ, whereas XML-based configuration is Spring proprietary. Because AspectJ is supported by an increasing number of AOP frameworks, facets written in annotation style will have more opportunities for reuse.

Well, let's talk about it in an example. We re-build a package that builds core business classes and slicing classes:

Core class: Subtraction Computing

Slice 1: Data validation

Tangent 2: Output log

package com.happbks.spring.aopbasic.aop2;public  class AtithmeticCalculateImpl implements AtithmeticCalculate {public int  Add (Int a, int b)  {int result=a+b;return result;} Public int sub (Int a, int b)  {int result=a-b;return result;} Public int mul (Int a, int b)  {int result=a*b;return result;} Public int div (Int a, int b)  {int result=a/b;return result;}} 

package com.happbks.spring.aopbasic.aop2;public  class AtithmeticCalculateImpl implements AtithmeticCalculate {public int  Add (Int a, int b)  {int result=a+b;return result;} Public int sub (Int a, int b)  {int result=a-b;return result;} Public int mul (Int a, int b)  {int result=a*b;return result;} Public int div (Int a, int b)  {int result=a/b;return result;}} 

package com.happbks.spring.aopbasic.aop2;import  java.util.arrays;import java.util.list;import org.aspectj.lang.joinpoint;public class  datavalidateaspect {public boolean beforemethod (Joinpoint joinpoint) {String  Methodname=joinpoint.getsignature (). GetName (); List<object> args=arrays.aslist (Joinpoint.getargs ()); System.out.println ("Data validate---begin to " +methodname+ " with " +args "); if ((Integer) (Args.get (0)) >0&& (Integer) (Args.get (1)) >0) {System.out.println ("Data is ok"); return  true;} Else{system.out.println ("Data is bad"); return false;}} 

Package com.happbks.spring.aopbasic.aop2;import java.util.arrays;import java.util.list;import  org.aspectj.lang.JoinPoint;import org.aspectj.lang.ProceedingJoinPoint;public class  loggingaspect {/* *  executes before each method of each implementation class of the Com.happBKs.spring.aopbasic.aop1.AtithmeticCalculate interface starts  */public void beforemethod (joinpoint joinpoint) {string methodname= Joinpoint.getsignature (). GetName (); List<object> args=arrays.aslist (Joinpoint.getargs ()); System.out.println ("begin to " +methodname+ " with " +args);} /* *  after the target method executes (whether or not an exception occurs), execute the notification  */public void aftermethod (joinpoint joinpoint) { String methodname=joinpoint.getsignature (). GetName (); System.out.println ("end to " +methodname); /* *  Code  *  return notification that executes after the target method has been executed normally is  */public void afterreturning that can access the return value of the target method ( Joinpoint joinpoint, object resultparam) {STRING&NBSP;METHODNAME=JOINPOint.getsignature (). GetName (); System.out.println ("after " +methodname+ " with returning result " +resultparam);} /* *  code  *  can access the exception object when an exception occurs in the target method, and can specify that code is executed at a specific exception  */public void  Afterthrowing (joinpoint joinpoint, exception exthrowing) {string methodname= Joinpoint.getsignature (). GetName (); System.out.println ("after exception of " +methodname+ " we find the exception  is  "+exthrowing);} /* *  loopback notifications need to carry Proceedingjoinpoint type parameters  *  Loopback notifications are similar to the whole process of dynamic agents: Parameters of the Proceedingjoinpoint type can determine whether to execute the target method  *  and the loopback notification must have a return value, which is the return value of the target method  */public  Object roundingmethod (PROCEEDINGJOINPOINT&NBSP;PJP) {object result=null; String methodname=pjp.getsignature (). GetName () try {//Pre-notification System.out.println ("Around: begin  method "+methodname+"  executed with  "+arrays.aslist (Pjp.getargs ()));result=  Pjp.proceed ();//Return Notification System.out.println ("ArOund: return method "+methodname+"   with result "+result);}  catch  (throwable e)  {// TODO Auto-generated catch  Blocke.printstacktrace ();//Exception Notification System.out.println ("around: exception in " +methodname+ ":" +e  );} Post-Notification System.out.println ("Around: end method" +methodname); return 100;}}

Above these classes, we no longer need to add a variety of annotations, all facets, notifications, pointcuts, etc. we are configured in the configuration file:

New configuration file Applicationcontext-xml.xml. (Join beans and AOP namespaces)

<?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.xsdhttp://www.springframework.org/schema/aop http://www.springframework.org/ Schema/aop/spring-aop-4.1.xsd "><!--  Configure bean --><bean id=" Atithmeticcalculate "class=" Com.happBKs.spring.aopbasic.aop2.AtithmeticCalculateImpl "></bean><!--  configuration facets bean --> <bean id= "Datavalidateaspect"  class= "Com.happBKs.spring.aopbasic.aop2.DataValidateAspect" >< /bean><bean id= "Loggingaspect"  class= "Com.happBKs.spring.aopbasic.aop2.LoggingAspect" ></ bean><!--  Configure aop --><aop:config><!--  Configure pointcut Expressions  --><aop:pointcut  Id= "Pointcutdata" expression= "Execution (* com.happbks.spring.aopbasic.aop2.atithmeticcalculateimpl.* (..))"  /><!--  Configuration facets and notifications  --><aop:aspect ref= "Datavalidateaspect"  order= "2" >< Aop:before method= "Beforemethod"  pointcut-ref= "Pointcutdata" &NBSP;/&GT;&LT;/AOP:ASPECT&GT;&LT;AOP: aspect ref= "Loggingaspect"  order= "1" ><aop:before method= "Beforemethod"  pointcut-ref= "Pointcutdata"  /><aop:after method= "Aftermethod"  pointcut-ref= "PointCutData"/&GT;&LT;AOP: After-throwing method= "afterthrowing"  pointcut-ref= "Pointcutdata"  throwing= "exThrowing"/> <aop:after-returning method= "afterreturning"  pointcut-ref= "Pointcutdata"  returning= " Resultparam "/><aop:around method=" Roundingmethod " pointcut-ref=" PointCutData " /></ Aop:aspect></aop:config></beans>

Here are the steps:

1, first configure all the original object's beans.

2, then configure all the slice beans, configure the bean ID of the slice to map the slice class.

3, configuring AOP

(1) Configure tangency point: A notification that relates to which methods are executed when the relevant facets are called. The tangent is configured first, and a reference is kept for a while.

(2) Configure each facet:

A. Configures the mapping of the slice Bean's ID to the order plane priority, and the individual notifications within the slice.

B. Configures the mapping of notifications and pointcuts within individual facets, and the pointcut is given as a reference.

Test code:

package com.happbks.spring.aopbasic;import org.junit.test;import  org.springframework.context.applicationcontext;import  org.springframework.context.support.classpathxmlapplicationcontext;import  com.happbks.spring.aopbasic.aop2.atithmeticcalculate;public class testspringaop2 {@Testpublic  VOID TESTSPRINGAOP () {//1.  Create a spring   IOC  container applicationcontext ac=new  Classpathxmlapplicationcontext ("Applicationcontext-xml.xml");//2.  gets the bean instance from the IOC container atithmeticcalculate  atithmeticcalculate =  (atithmeticcalculate) Ac.getbean (atithmeticcalculate.class);// Examine whether the proxy object generates SYSTEM.OUT.PRINTLN (Atithmeticcalculate.getclass (). GetName ());//3.  use BeanSystem.out.println (" Example 1: "); Int result=atithmeticcalculate.add (10, 5); SYSTEM.OUT.PRINTLN (result); System.out.println ("\r\nexample 2:"); Int result2=atithmeticcalculate.div (10, 0); System.out.println (RESULT2);}}

Operation Result:

Com.sun.proxy. $Proxy 4

Example 1:

Begin to add with [10, 5]

Around:begin Methodadd executed with [10, 5]

Data Validate---Begin to add with [10, 5]

Data is OK

Around:return Methodadd with result15

Around:end Methodadd

After add with returning result 100

End to add

100

Example 2:

Begin to Div with [10, 0]

Around:begin Methoddiv executed with [10, 0]

Data Validate---Begin to div with [10, 0]

Data is bad

Java.lang.ArithmeticException:/By zero

at Com.happBKs.spring.aopbasic.aop2.AtithmeticCalculateImpl.div (atithmeticcalculateimpl.java:24)

at Sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)

at Sun.reflect.NativeMethodAccessorImpl.invoke (Unknown Source)

at Sun.reflect.DelegatingMethodAccessorImpl.invoke (Unknown Source)

at Java.lang.reflect.Method.invoke (Unknown Source)

at Org.springframework.aop.support.AopUtils.invokeJoinpointUsingReflection (aoputils.java:317)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.invokeJoinpoint ( reflectivemethodinvocation.java:190)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:157)

at Org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke ( METHODBEFOREADVICEINTERCEPTOR.JAVA:52)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.aspectj.MethodInvocationProceedingJoinPoint.proceed ( METHODINVOCATIONPROCEEDINGJOINPOINT.JAVA:85)

at Com.happBKs.spring.aopbasic.aop2.LoggingAspect.roundingMethod (loggingaspect.java:76)

at Sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)

at Sun.reflect.NativeMethodAccessorImpl.invoke (Unknown Source)

at Sun.reflect.DelegatingMethodAccessorImpl.invoke (Unknown Source)

at Java.lang.reflect.Method.invoke (Unknown Source)

at Org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethodWithGivenArgs ( abstractaspectjadvice.java:621)

at Org.springframework.aop.aspectj.AbstractAspectJAdvice.invokeAdviceMethod (Abstractaspectjadvice.java : 610)

at Org.springframework.aop.aspectj.AspectJAroundAdvice.invoke (aspectjaroundadvice.java:68)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.framework.adapter.AfterReturningAdviceInterceptor.invoke ( AFTERRETURNINGADVICEINTERCEPTOR.JAVA:52)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke (Aspectjafterthrowingadvice.java : 58)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.aspectj.AspectJAfterAdvice.invoke (aspectjafteradvice.java:43)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.framework.adapter.MethodBeforeAdviceInterceptor.invoke ( METHODBEFOREADVICEINTERCEPTOR.JAVA:52)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke ( exposeinvocationinterceptor.java:92)

at Org.springframework.aop.framework.ReflectiveMethodInvocation.proceed ( reflectivemethodinvocation.java:179)

at Org.springframework.aop.framework.JdkDynamicAopProxy.invoke (jdkdynamicaopproxy.java:207)

at Com.sun.proxy. $Proxy 4.div (Unknown Source)

at Com.happBKs.spring.aopbasic.TestSpringAOP2.testSpringAOP (testspringaop2.java:24)

at Sun.reflect.NativeMethodAccessorImpl.invoke0 (Native Method)

at Sun.reflect.NativeMethodAccessorImpl.invoke (Unknown Source)

at Sun.reflect.DelegatingMethodAccessorImpl.invoke (Unknown Source)

at Java.lang.reflect.Method.invoke (Unknown Source)

at Org.junit.runners.model.frameworkmethod$1.runreflectivecall (frameworkmethod.java:45)

at Org.junit.internal.runners.model.ReflectiveCallable.run (reflectivecallable.java:15)

at org.junit.runners.model.FrameworkMethod.invokeExplosively (frameworkmethod.java:42)

at Org.junit.internal.runners.statements.InvokeMethod.evaluate (invokemethod.java:20)

at Org.junit.runners.ParentRunner.runLeaf (parentrunner.java:263)

at Org.junit.runners.BlockJUnit4ClassRunner.runChild (blockjunit4classrunner.java:68)

at Org.junit.runners.BlockJUnit4ClassRunner.runChild (blockjunit4classrunner.java:47)

at Org.junit.runners.parentrunner$3.run (parentrunner.java:231)

at Org.junit.runners.parentrunner$1.schedule (parentrunner.java:60)

at Org.junit.runners.ParentRunner.runChildren (parentrunner.java:229)

at org.junit.runners.parentrunner.access$000 (parentrunner.java:50)

at Org.junit.runners.parentrunner$2.evaluate (parentrunner.java:222)

at Org.junit.runners.ParentRunner.run (parentrunner.java:300)

at Org.eclipse.jdt.internal.junit4.runner.JUnit4TestReference.run (junit4testreference.java:50)

at Org.eclipse.jdt.internal.junit.runner.TestExecution.run (testexecution.java:38)

at Org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests (remotetestrunner.java:459)

at Org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.runTests (remotetestrunner.java:675)

at Org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.run (remotetestrunner.java:382)

at Org.eclipse.jdt.internal.junit.runner.RemoteTestRunner.main (remotetestrunner.java:192)

Around:exception in Div:java.lang.ArithmeticException:/by zero

Around:end Methoddiv

After div with returning result 100

End to Div

100

Spring Framework Notes (23)--Configuring AOP based on configuration files