Spring AOP基於XML的After Throwing Advice

after-throwing是一種通知型別，只有在方法通過丟擲異常退出時才能確保方法執行後才能執行通知。以下是after-throwing通知的語法：

語法

<aop:config>
   <aop:aspect id="log" ref="logging">
      <aop:pointcut id="pointcut-id" expression="execution( expression )"/>    
      <aop:after-throwing pointcut-ref="pointcut-id" throwing="ex" method="methodName"/>
   </aop:aspect>
   </aop:config>

在上面組態中，

pointcut-id - 切入點的id。
ex - 要被被丟擲例外。
methodName - 在呼叫函式之前呼叫的函式的方法名稱。

要了解上述與之後丟擲通知(After Throwing Advice)相關的概念，寫一個在實現之後丟擲通知(After Throwing Advice)的範例。為了簡單，可直接複製之前上一篇文章中的例子，開啟並使用Eclipse IDE，並按照以下步驟建立一個Spring應用程式：

更新在Spring AOP應用範例中建立過的Student專案。
更新bean組態並執行應用程式，如下所述。

整個專案的目錄結構如下所示 -

下面是Logging.java檔案的內容。這實際上是一個Aspect模組的樣本，它定義了在各個點被呼叫的方法。

package com.yiibai;

public class Logging {
    /**
    * This is the method which I would like to execute
    * if there is an exception raised.
    */
   public void afterThrowingAdvice(IllegalArgumentException ex){
      System.out.println("[afterThrowingAdvice] There has been an exception: " + ex.toString());   
   } 
}

以下是Student.java檔案的內容：

package com.yiibai;

public class Student {
   private Integer age;
   private String name;

   public void setAge(Integer age) {
      this.age = age;
   }
   public Integer getAge() {
      System.out.println("Age : " + age );
      System.out.println("Exception raised");
      throw new IllegalArgumentException();
      return age;
   }

   public void setName(String name) {
      this.name = name;
   }
   public String getName() {
      System.out.println("Name : " + name );
      return name;
   }

   public void printThrowException(){
       System.out.println("Exception raised");
       throw new IllegalArgumentException();
   }
}

以下是MainApp.java檔案的內容：

package com.yiibai;

import org.springframework.context.ApplicationContext;
import org.springframework.context.support.ClassPathXmlApplicationContext;

public class MainApp {
   public static void main(String[] args) {
      ApplicationContext context = 
             new ClassPathXmlApplicationContext("Beans.xml");

      Student student = (Student) context.getBean("student");

      student.printThrowException();     
   }
}

以下是組態檔案Beans.xml檔案的內容：

<?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-3.0.xsd 
    http://www.springframework.org/schema/aop 
    http://www.springframework.org/schema/aop/spring-aop-3.0.xsd ">

   <aop:config>
      <aop:aspect id="log" ref="logging">
         <aop:pointcut id="selectAll" 
         expression="execution(* com.yiibai.*.*(..))"/>
         <aop:after-throwing pointcut-ref="selectAll" throwing="ex" method="afterThrowingAdvice"/>         
      </aop:aspect>
   </aop:config>

   <!-- Definition for student bean -->
   <bean id="student" class="com.yiibai.Student">
        <property name="name" value="maxsu" />
        <property name="age" value="25" />
    </bean>

   <!-- Definition for logging aspect -->
   <bean id="logging" class="com.yiibai.Logging"/> 

</beans>

執行專案

完成建立原始碼和組態檔案後，執行應用程式。右鍵單擊應用程式中的MainApp.java，並使用執行方式作為Java應用程式命令。如果您的應用程式一切正常，這將列印以下訊息：

Exception raised
[afterThrowingAdvice] There has been an exception: java.lang.IllegalArgumentException
Exception in thread "main" java.lang.IllegalArgumentException
    at com.yiibai.Student.printThrowException(Student.java:27)
    at com.yiibai.Student$$FastClassBySpringCGLIB$$e9280b4b.invoke(<generated>)
    at org.springframework.cglib.proxy.MethodProxy.invoke(MethodProxy.java:204)
    at org.springframework.aop.framework.CglibAopProxy$CglibMethodInvocation.invokeJoinpoint(CglibAopProxy.java:717)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:157)
    at org.springframework.aop.aspectj.AspectJAfterThrowingAdvice.invoke(AspectJAfterThrowingAdvice.java:58)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:92)
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:179)
    at org.springframework.aop.framework.CglibAopProxy$DynamicAdvisedInterceptor.intercept(CglibAopProxy.java:653)
    at com.yiibai.Student$$EnhancerBySpringCGLIB$$47620070.printThrowException(<generated>)
    at com.yiibai.MainApp.main(MainApp.java:13)