实例讲解DispatchAction和LookupDispatchAction

< %@ taglib  uri ="http://struts.apache.org/tags-logic"  prefix ="logic"% > 
< %@taglib  prefix ="c"  uri ="http://java.sun.com/jsp/jstl/core"% > 
< html > 
   < head > 
     < title >DispatchAction Example - viralpatel.net </title> 
   </head> 
   < body > 
     < h2 > 
      User Management (DispatchAction Example) 
     </h2> 
     < font  color ="black" > < h3 > 
        用struts标签的方法 
       </h3>  </font> 
     < html:form  action ="/user"  method ="post" > 
       < html:text  property ="userName"  /> 
       < html:submit  property ="method"  value ="create"  /> 
       < html:submit  property ="method"  value ="delete"  /> 
     </html:form> 
     < font  color ="black" > < h3 > 
        不用struts标签的方法 
       </h3>  </font> 
     < form  action ="/struts_action_test/user.do"  method ="post" > 
       < input  type ="text"  name ="userName" /> 
       < input  type ="submit"  name ="method"  value ="create" /> 
       < input  type ="submit"  name ="method"  value ="delete" /> 
     </form> 
     < font  color ="blue" > < h3 > 
        ${message } 
       </h3>  </font> 现有以下用户： 
     < c:forEach  var ="numArray"  items ="${num}" > 
       < table > 
         < tr > 
           < td > 
             < c:out  value ="${numArray}"  /> 
           </td> 
         </tr> 
       </table> 
     </c:forEach> 
   </body> 
</html>

package com.zgxr.struts; 

import java.lang.reflect.Array; 
import java.util.ArrayList; 
import java.util.List; 

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

import org.apache.struts.action.ActionForm; 
import org.apache.struts.action.ActionForward; 
import org.apache.struts.action.ActionMapping; 
import org.apache.struts.actions.DispatchAction; 

public  class UserManagementAction  extends DispatchAction { 
   // 用于存放添加的用户 
  List list =  new ArrayList(); 
   public ActionForward create(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response) 
       throws Exception { 
    LoginActionForm loginActionForm = (LoginActionForm) form; 
     // 将新添加的用户放入list 
    list.add(loginActionForm.getUserName()); 
    request.setAttribute( "message",  "User created successfully" +  ":" 
        +  "当前用户数量为:" + list.size()); 
     
    request.setAttribute( "num", list); 
     return mapping.findForward( "success"); 
  } 

   public ActionForward delete(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response) 
       throws Exception { 
    LoginActionForm loginActionForm = (LoginActionForm) form; 
     //将提交上来的用户从List中删除 
    list.remove(loginActionForm.getUserName()); 
    request.setAttribute( "message",  "User deleted successfully" +  ":" 
        +  "当前用户数量为:" + list.size()); 
    request.setAttribute( "num", list); 
     return mapping.findForward( "success"); 
  } 

}

package com.zgxr.struts; 

import org.apache.struts.action.ActionForm; 

public  class LoginActionForm  extends ActionForm { 
   // 定义两个变量，这两个值与页面上的html:text的property的值相对应 
   private  int numOne; 
   private  int numTwo; 
   private String userName; 

   public String getUserName() { 
     return userName; 
  } 

   public  void setUserName(String userName) { 
     this.userName = userName; 
  } 

   public  int getNumOne() { 
     return numOne; 
  } 

   public  void setNumOne( int numOne) { 
     this.numOne = numOne; 
  } 

   public  int getNumTwo() { 
     return numTwo; 
  } 

   public  void setNumTwo( int numTwo) { 
     this.numTwo = numTwo; 
  } 

}

<? 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 > 
   < form-beans > 
     < form-bean  name ="loginActionForm" 
       type ="com.zgxr.struts.LoginActionForm" > 
     </ form-bean > 
   </ form-beans > 
   < action-mappings > 
     < action  path ="/user"  parameter ="method"  name ="loginActionForm" 
       type ="com.zgxr.struts.UserManagementAction" > 
       < forward  name ="success"  path ="/UserManagement.jsp"  /> 
       < forward  name ="failure"  path ="/UserManagement.jsp"  /> 
     </ action > 

     < action  path ="/test"  name ="loginActionForm"  scope ="request" 
       parameter ="action"  type ="com.zgxr.struts.TestAction" 
       input ="/operation.jsp" > 
       < forward  name ="success"  path ="/operation.jsp"  /> 
       < forward  name ="failure"  path ="/operation.jsp"  /> 
     </ action > 
   </ action-mappings > 
   < message-resources  parameter ="ApplicationResources"  /> 
</ struts-config >

%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> 
< %@ taglib  uri ="http://struts.apache.org/tags-html"  prefix ="html"% > 
< %@ taglib  prefix ="bean"  uri ="http://struts.apache.org/tags-bean"% > 

< !DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" > 
< html > 
   < head > 
     < title >LookupDispatchAction Example - viralpatel.net </title> 
   </head> 
   < body > 
     < h2 > 
      User Management (LookupDispatch Action Example) 
     </h2> 
                            用struts标签的方法 
     < html:form  action ="/test"  method ="post" > 
       < html:text  property ="numOne" /> 
       < html:text  property ="numTwo" /> 
       < html:submit  property ="action" > 
         < bean:message     key ="button.sum" /> 
       </html:submit> 
       < html:submit  property ="action" > 
         < bean:message  key ="button.minus" /> 
       </html:submit> 
       < html:submit  property ="action" > 
         < bean:message  key ="button.multiply" /> 
       </html:submit> 
       < html:submit  property ="action" > 
         < bean:message  key ="button.divide" /> 
       </html:submit> 
     </html:form> 
                             不用struts标签的方法 
                             < form  name ="loginActionForm"  method ="post" action="/struts_action_test/test.do > 
       < input  type ="text"  name ="numOne" /> 
       < input  type ="text"  name ="numTwo" /> 
       < input  type ="submit"  name ="action"  value ="sum" /> 
       < input  type ="submit"  name ="action"  value ="minus" > 
       < input  type ="submit"  name ="action"  value ="multiply" /> 
       < input  type ="submit"  name ="action"  value ="divide" /> 
     </form> 
   </body> 
</html>

package com.zgxr.struts; 

import java.util.HashMap; 
import java.util.Map; 

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

import org.apache.struts.action.ActionForm; 
import org.apache.struts.action.ActionForward; 
import org.apache.struts.action.ActionMapping; 
import org.apache.struts.actions.LookupDispatchAction; 

public  class TestAction  extends LookupDispatchAction { 

  @Override 
   //用于关联按键和方法 
   protected Map getKeyMethodMap() { 
    Map map =  new HashMap(); 
     //如果按钮标题的key为button.sum. 则提交该按钮时对应sum方法 
    map.put( "button.sum",  "sum"); 
     //如果按钮标题的key为button.minus. 则提交该按钮时对应minus方法 
    map.put( "button.minus",  "minus"); 
     //如果按钮标题的key为button.multiply. 则提交该按钮时对应multiply方法 
    map.put( "button.multiply",  "multiply"); 
     //如果按钮标题的key为button.divide. 则提交该按钮时对应divide方法 
    map.put( "button.divide",  "divide"); 
     return map; 
  } 

   public ActionForward sum(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response) 
       throws Exception { 
     //将form转变成提交时用到的loginActonForm 
    LoginActionForm loginActionForm = (LoginActionForm) form; 
     //计算加法 
     int num = loginActionForm.getNumOne() + loginActionForm.getNumTwo(); 
    request.setAttribute( "action", num); 
     return mapping.findForward( "success"); 
  } 

   public ActionForward minus(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response) 
       throws Exception { 
     //将form转变成提交时用到的loginActonForm 
    LoginActionForm loginActionForm = (LoginActionForm) form; 
     //计算减法 
     int num = loginActionForm.getNumOne() - loginActionForm.getNumTwo(); 
    request.setAttribute( "action", num); 
     return mapping.findForward( "success"); 
  } 

   public ActionForward multiply(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response) 
       throws Exception { 
     //将form转变成提交时用到的loginActonForm 
    LoginActionForm loginActionForm = (LoginActionForm) form; 
     //计算乘法 
     int num = loginActionForm.getNumOne() * loginActionForm.getNumTwo(); 
    request.setAttribute( "action", num); 
     return mapping.findForward( "success"); 
  } 

   public ActionForward divide(ActionMapping mapping, ActionForm form, 
      HttpServletRequest request, HttpServletResponse response) 
       throws Exception { 
     //将form转变成提交时用到的loginActonForm 
    LoginActionForm loginActionForm = (LoginActionForm) form; 
     //计算除法 
     int num = loginActionForm.getNumOne() / loginActionForm.getNumTwo(); 
    request.setAttribute( "action", num); 
     return mapping.findForward( "success"); 
  } 
}

button.sum=sum 
button.minus=minus 
button.multiply=multiply 
button.divide=divide

<? xml  version ="1.0"  encoding ="UTF-8" ?> 
< web-app  xmlns ="http://java.sun.com/xml/ns/javaee" 
   xmlns:xsi ="http://www.w3.org/2001/XMLSchema-instance"  version ="2.5" 
   xsi:schemaLocation ="http://java.sun.com/xml/ns/javaee     http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" > 
   < servlet > 
     < servlet-name >action </ servlet-name > 
     < servlet-class > 
      org.apache.struts.action.ActionServlet 
     </ servlet-class > 
     < init-param > 
       < param-name >application </ param-name > 
       < param-value >ApplicationResources </ param-value > 
     </ init-param > 
     < init-param > 
       < param-name >config </ param-name > 
       < param-value >/WEB-INF/struts-config.xml </ param-value > 
     </ init-param > 
     < init-param > 
       < param-name >debug </ param-name > 
       < param-value >3 </ param-value > 
     </ init-param > 
     < init-param > 
       < param-name >detail </ param-name > 
       < param-value >3 </ param-value > 
     </ init-param > 
     < load-on-startup >0 </ load-on-startup > 
   </ servlet > 
   < servlet-mapping > 
     < servlet-name >action </ servlet-name > 
     < url-pattern >*.do </ url-pattern > 
   </ servlet-mapping > 
   < welcome-file-list > 
     < welcome-file >/UserManagement.jsp </ welcome-file > 
   </ welcome-file-list > 
</ web-app >