我們?cè)诩蒘pring和struts的時(shí)候，往往習(xí)慣于使用spring提供的ActionSupport,然后使用getWebApplicationContext()方法獲得spring的bean,這樣固然方便，但有一個(gè)弊端，就是我們的struts action依賴了spring的api，增加了耦合，現(xiàn)在什么都流行高內(nèi)聚，低耦合，spring為我們提供了代理的Struts action,這樣，我們?cè)趕truts-config.xml不再為path設(shè)置真正的action,而是設(shè)計(jì)spring的代理Action,然后由spring的代理action,去尋找在spring bean 容器中的真正的action,這樣，我們的action是一個(gè)完全沒(méi)有依賴于spring的action?，具體實(shí)現(xiàn)請(qǐng)看以下代碼：

?

Action:

?

/**/ /*
?*?Generated?by?MyEclipse?Struts
?*?Template?path:?templates/java/JavaClass.vtl
? */
package ?action;

import ?javax.servlet.http.HttpServletRequest;
import ?javax.servlet.http.HttpServletResponse;

import ?org.apache.struts.action.Action;
import ?org.apache.struts.action.ActionForm;
import ?org.apache.struts.action.ActionForward;
import ?org.apache.struts.action.ActionMapping;

import ?Service.StudentService;


public ? class ?ListStudentActionAction? extends ?Action? ... {
???? private ?StudentService?studentService;
???? public ?ActionForward?execute(ActionMapping?mapping,?ActionForm?form,
????????????HttpServletRequest?request,?HttpServletResponse?response)? ... {

????????System.out.println( this .studentService.getStudent().getName() + " -- " + this .studentService.getStudent().getSex());
???????? return ? null ;
????}
???? // 通過(guò)spring注入service
???? public ? void ?setStudentService(StudentService?studentService)? ... {
???????? this .studentService? = ?studentService;
????}
????
????
}

?

Service：

?

package?Service;

import?Model.Student;

public?class?StudentService?{

??public?Student?getStudent(){
?????return?new?Student("name","sex");??
??}
}

?

applicationContext.xml

配置真正的strutsAction,并把service類注入

<? xml?version="1.0"?encoding="UTF-8" ?>
< beans
???? xmlns ="http://www.springframework.org/schema/beans"
????xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"
????xsi:schemaLocation ="http://www.springframework.org/schema/beans?http://www.springframework.org/schema/beans/spring-beans-2.0.xsd" >

< bean? name ="/listStudentAction" ?class ="action.ListStudentActionAction" >
?? < property? name ="studentService" >
???? < bean? class ="Service.StudentService" />
?? </ property >
</ bean >
</ beans >

?

struts-config.xml

?

<? xml?version="1.0"?encoding="UTF-8" ?>
<! DOCTYPE?struts-config?PUBLIC?"-//Apache?Software?Foundation//DTD?Struts?Configuration?1.2//EN"?"http://struts.apache.org/dtds/struts-config_1_2.dtd" >

< struts-config >
?? < data-sources? />
?? < form-beans? />
?? < global-exceptions? />
?? < global-forwards? />
?? < action-mappings? >
??? <!-- ?不再真正的action,而注冊(cè)spring的代理action
????<action?path="/listStudentAction"?type="action.ListStudentActionAction"?/>
?????? -->
???? < action? path ="/listStudentAction" ?type ="org.springframework.web.struts.DelegatingActionProxy" ? />


?? </ action-mappings >

??? < message-resources? parameter ="ApplicationResources" ? />


?

??? < plug-in? className ="org.springframework.web.struts.ContextLoaderPlugIn" >
???????? < set-property? property ="contextConfigLocation"
????????????value ="/WEB-INF/classes/applicationContext-service.xml" />
???? </ plug-in >
</ struts-config >

需要說(shuō)明的是，由于spring dtd規(guī)定id不能有"/",所以我們用name定義path,并且，spring bean的name要和struts-config.xml中的path一致

使用DelegatingActionProxy的好處就在于你可以用不用任何spring特定的類編寫Struts Action,這個(gè)方法也有不足之處，就是不太直觀，因?yàn)樗新窂蕉加成涞酵粋€(gè)類了

對(duì)于這種情況，spring也有解決方法，就是使用請(qǐng)求委托

首先，為struts-config.xml增加controller

?

?? <!-- ?使用請(qǐng)求委托? -->
? < controller? processorClass ="org.springframework.web.struts.DelegatingRequestProcessor" >
? </ controller >

?

然后，修改我們的path定義位 <action path="/listStudentAction" type="action.ListStudentActionAction"/>

這樣，又和我們單獨(dú)使用struts的時(shí)候一樣了，但內(nèi)部還是讓spring取代理我們的真正的action

需要說(shuō)明的是，這里的type其實(shí)是個(gè)擺設(shè)，完全可以使用 <action path="/listStudentAction"/>，寫上是為了解決我們上面提到的“不夠直觀的”的問(wèn)題

低耦合的Struts集成Spring的實(shí)例