Spring’s AOP with Struts

Using Spring’s AOP with your Struts Application:

To tackle cross-cutting you can use Spring interceptors
To use Spring’s AOP in your Struts Applications you need to :

1. Create the interceptor.
2. Registor the interceptor.
3. Delclare interceptors.

For example
A sample logging interceptor

  
package net.champ.example1.employee.interceptors;

import org.springframework.aop.MethodBeforeAdvice;
import java.lang.reflect.Method;

public class LoggingInterceptor implements MethodBeforeAdvice {

   public void beforeMethod(Method method, Object[] objects, Object o) throws Throwable {
        System.out.println("logging before intersection");
    }
}

This interceptor will execute the beforeMethod() before every intersection (We are using MethodBeforeAdvice). Here we are just printing a line but we can use it for anything we like. Next let us register the interceptor.
Registering the interceptor in the Spring config file

  
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE beans PUBLIC "-//SPRING//DTD BEAN//EN"
  "http://www.springframework.org/dtd/spring-beans.dtd">

<beans>
  <bean id="empSearchService" class="net.champ.example1.employee.business.EmpSearchServiceImpl">
  <bean name="/submitSearch"
        class="net.champ.example1.employee.actions.SubmitSearch">
     <property name="empSearchService">
        <ref bean="empSearchService">
     </property>
  </bean>

  <!--  Interceptors -->
  <bean name="logger"   
    class="net.champ.example1.employee.interceptors.LoggingInterceptor"/>
  <!-- AutoProxies -->
  <bean name="loggingAutoProxy"
        class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator">
    <property name="beanNames">
          <value>/submitSearch>/values>
    </property>
    <property name="interceptorNames">
        <list>
          <value>logger>/value>
        </list>
    </property>
   </bean>

</beans>

Explanation:
First we have to register the interceptor:

 
<bean name="logger"   
    class="net.champ.example1.employee.interceptors.LoggingInterceptor"/>

Now we need to define the intersections, we will use autoproxy:

 <bean name="loggingAutoProxy"
        class="org.springframework.aop.framework.autoproxy.BeanNameAutoProxyCreator">

Now we have to register the Struts action’s that will be intercepted.

<property name="beanNames">
          <value>/submitSearch>/values>
//        <value>/otherBeans>/values>          
    </property>

Apply interceptors to the beanNames:

    <property name="interceptorNames">
        <list>
          <value>logger>/value>
        </list>
    </property>