在WebWork中實現自己的Result Type

飛雲小俠 2005-7-27  http://www.jscud.com 轉載請註明作者

我在項目中經常用到這樣的功能:例如添加完一個文章,我通常會提示使用者"操作完成",然後轉向到文章列表頁面或者文章詳情頁面.以前的做法是使用WebWork本身的dispatcher結果類型,設定結果頁面為資訊提示頁面,在程式中設定目標頁面和提示資訊.這樣雖然也可以完成我的目標,但是目標頁面是在程式裡面寫死的,無法放在配置裡.

這幾天研究了一下WebWork的Result Type,發現寫一個新的Result Type很容易,於是誕生了我的一個新的Result Type:

功能:資訊提示並轉向到目標頁面
流程:在Action中設定提示資訊(當然也可以改到設定檔裡,但是配置起來略麻煩,所以還是寫在程式裡了),然後使用我的結果類型msgto,在設定檔裡面配置目標頁面.

代碼如下

1.頁面資訊提示類(包含頁面提示資訊和目標頁面,停留時間)

 

package com.jscud.www.support.web;      /*   * Created Date  2004-11-23   *   */    /**   * 用於頁面提示的資訊類.   *   * @author scud   *    */  public class PageMessage  {      /**標題*/      private String msgTitle;        /**內容體*/      private String msgContent;        /**要轉向到的網址*/      private String msgToURL;        /**停留時間*/      private int msgToTime = 1 ;             public String getMsgContent()      {          return msgContent;      }        public void setMsgContent(String msgContent)      {          this.msgContent = msgContent;      }        public String getMsgTitle()      {          return msgTitle;      }        public void setMsgTitle(String msgTitle)      {          this.msgTitle = msgTitle;      }        public int getMsgToTime()      {                   return msgToTime;      }        public void setMsgToTime(int msgToTime)      {          this.msgToTime = msgToTime;      }        public String getMsgToURL()      {          return msgToURL;      }        public void setMsgToURL(String msgToURL)      {          this.msgToURL = msgToURL;      }  }

 
 
 
2."msgto" Result Type ,借鑒了WebWork本身的幾個ResultType,部分代碼是copy過來的

 

package com.jscud.www.support.web;    //import com.jscud.util.LogMan;  import com.opensymphony.webwork.config.Configuration;  import com.opensymphony.webwork.dispatcher.ServletDispatcher;  import com.opensymphony.webwork.dispatcher.WebWorkResultSupport;    import com.opensymphony.webwork.ServletActionContext;  import com.opensymphony.xwork.ActionContext;  import com.opensymphony.xwork.ActionInvocation;  import com.opensymphony.xwork.util.OgnlValueStack;    import javax.servlet.RequestDispatcher;  import javax.servlet.http.HttpServletRequest;  import javax.servlet.http.HttpServletResponse;    /*   * Created on 2005-7-26   *   */    /**   * WebWork Result Type for "msgto".   *   * Message Hint to User then Refresh to another Page.   *   * @author scud.   *   */  public class ServletMessageToResult extends WebWorkResultSupport  {        //~ Static fields/initializers /////////////////////////////////////////////        private static final String DefaultMessagePage = "/WEB-INF/public/page/msgto.jsp";        protected String messagePage;           protected boolean prependServletContext = true;          //~ Methods ////////////////////////////////////////////////////////////////        public void setMessagePage(String sPagePath)      {          this.messagePage = sPagePath;      }        public String getMessagePage()      {          if (null == messagePage)          {              if (Configuration.isSet("jscud.page.messageto"))              {                  this.messagePage = Configuration.getString("jscud.page.messageto");              }              else              {                  this.messagePage = DefaultMessagePage;              }          }            return messagePage;      }             /**       * Sets whether or not to prepend the servlet context path to the redirected URL.       *       * @param prependServletContext <tt>true</tt> to prepend the location with the servlet context path,       *                              <tt>false</tt> otherwise.       */      public void setPrependServletContext(boolean prependServletContext) {          this.prependServletContext = prependServletContext;      }           /**       * Dispatches to the Message Page. Does its forward via a RequestDispatcher. If the       * dispatch fails a 404 error will be sent back in the http response.       *       * @param finalLocation the location to dispatch to.       * @param invocation    the execution state of the action       * @throws Exception if an error occurs. If the dispatch fails the error will go back via the       *                   HTTP request.       */      public void doExecute(String finalLocation, ActionInvocation invocation)              throws Exception      {          String messageLocation = getMessagePage();            HttpServletRequest request = ServletActionContext.getRequest();          HttpServletResponse response = ServletActionContext.getResponse();            RequestDispatcher dispatcher = request.getRequestDispatcher(messageLocation);            // if the view doesn't exist, let's do a 404          if (dispatcher == null)          {              response.sendError(404, "message page '" + messageLocation + "' not found");                return;          }            request.setAttribute("webwork.view_uri", messageLocation);          request.setAttribute("webwork.request_uri", request.getRequestURI());            //set refresh target url          if (isPathUrl(finalLocation))          {              if (!finalLocation.startsWith("/"))              {                  String actionPath = request.getServletPath();                  String namespace = ServletDispatcher                          .getNamespaceFromServletPath(actionPath);                    if ((namespace != null) && (namespace.length() > 0))                  {                      finalLocation = namespace + "/" + finalLocation;                  }                  else                  {                      finalLocation = "/" + finalLocation;                  }              }                // if the URL's are relative to the servlet context, append the servlet context path              if (prependServletContext && (request.getContextPath() != null)                      && (request.getContextPath().length() > 0))              {                  finalLocation = request.getContextPath() + finalLocation;              }                finalLocation = response.encodeRedirectURL(finalLocation);          }            //LogMan.debug("Refreshing to finalLocation " + finalLocation);                   //設定屬性          OgnlValueStack stack = ActionContext.getContext().getValueStack();                   PageMessage aPageMessage = (PageMessage)stack.findValue("pagemessage",PageMessage.class);                   if(null!=aPageMessage)          {              aPageMessage.setMsgToURL(finalLocation);          }                   dispatcher.forward(request, response);      }        //copy from ServletRedirectResult      private static boolean isPathUrl(String url)      {          // filter out "http:", "https:", "mailto:", "file:", "ftp:"          // since the only valid places for : in URL's is before the path specification          // either before the port, or after the protocol          return (url.indexOf(':') == -1);      }   }

 
3.資訊提示頁面

 預設為/WEB-INF/public/page/msgto.jsp,可以在webwork.properties裡面配置"jscud.page.messageto",還可以通過設定檔配置.
 
 可以根據自己需要更改頁面內容.
 
 

<%@ page contentType="text/html; charset=GBK" %>  <%@ taglib uri="webwork" prefix="ww" %>    <html>  <head>  <meta http-equiv="pragma" content="no-cache">  <meta http-equiv="Cache-Control" content="no-cache, must-revalidate">  <meta http-equiv="expires" content="0">    <meta http-equiv="Content-Type" content="text/html; charset=GBK">    <meta http-equiv="refresh" content="<ww:property value="pagemessage.msgToTime" />;URL=<ww:property value="pagemessage.msgToURL" />">    <title><ww:property value="pagemessage.msgTitle" /></title>  </head>  <body >  <div align=center>  <table width=90% border="0" cellspacing="0" cellpadding="0" align="center" bgcolor=#ffffff>    <tr valign="top">      <td width="2">       　      </td>      <td width="5"></td>      <td colspan="3">  <center><br><br>  <table align="center" border="0" cellpadding="5" cellspacing="0" width="100%">  <tbody>  <tr>  <td><ww:property value="pagemessage.msgTitle" />  <hr noshade size="1" color="#808000">  </td>  </tr>  <tr>  <td><ww:property value="pagemessage.msgContent" /><br><br><br>  請稍後......<br>  </td>  </tr>  </tbody>  </table>  </center>        </td>    </tr>  </table>    </div>  </body>  </html>

 
 
 
4.配置樣本

  

<result-types>    <result-type name="msgto" class="com.jscud.www.support.web.ServletMessageToResult" />   </result-types>   <action name="doAddCata" class="catagoryAction" method="doSet">    <result name="input" type="dispatcher">     <param name="location">/WEB-INF/jsp/news/catagory_add.jsp</param>    </result>    <result name="success" type="msgto">     <param name="location">/news/admin/admin.jspa</param>    </result>   </action>

   

5.Action中的程式碼範例

 

/**      * 增加/編輯類別      *      * @return 結果      */     public String doSet()     {         //輸入介面         if (null == catagory)         {             return INPUT;         }         catagoryManager.updateCatagory(getCatagory(), getWork());             //return goException("設定分類時發生了錯誤",ex);         setPageMessageProp("操作成功", "操作成功");         return SUCCESS;     }

 
 
 
 以下代碼放在基礎Action裡:(自己要做適當修改)
 

/**      * 設定資訊提示的內容.      *      * @param sTitle      * @param sHintMsg      */     protected void setPageMessageProp(String sTitle, String sHintMsg)     {         PageMessage apm = new PageMessage();         if ((null == sTitle) || (sTitle.equals("")))         {             sTitle = getText("core.errorhint.title.default");         }         apm.setMsgTitle(sTitle);         apm.setMsgContent(sHintMsg);         setPagemessage(apm);     }     /**      * 設定資訊提示的參數.(轉向)      *      * @param sTitle      * @param sHintMsg      * @param toURL      * @param nToTime      */     protected void setPageMessageProp(String sTitle, String sHintMsg,int nToTime)     {         PageMessage apm = new PageMessage();         if ((null == sTitle) || (sTitle.equals("")))         {             sTitle = getText("core.errorhint.title.default");         }         apm.setMsgTitle(sTitle);         apm.setMsgContent(sHintMsg);         //apm.setMsgToURL(toURL);         apm.setMsgToTime(nToTime);         setPagemessage(apm);     }     public PageMessage getPagemessage()     {         return pagemessage;     }     public void setPagemessage(PageMessage pagemessage)     {         this.pagemessage = pagemessage;     }

 

 
 
ok,很簡單,不是嗎?