既然我們已經成功完成了第一個ActionForm Bean和與之相關的Action Class；后面的專題中將不再詳細的去寫與他們相關的開發步驟了。
現在我們開始寫留言板的主體部分，即對整個留言就行瀏覽。因為每個post都有一個replyId字段，用來對應其所回復的留言id；如果這個
replyId等于-1的話，即該留言沒有對應的回復。好了還是先從這個JSP頁面寫起。
- display.jsp
1 <%@page contentType="text/html" pageEncoding="UTF-8"%>
2 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"
3 "http://www.w3.org/TR/html4/loose.dtd">
4 <%@taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>
5 <%@taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
6 <%@taglib uri="http://struts.apache.org/tags-logic" prefix="logic" %>
7
8 <html>
9 <head>
10 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
11 <title>留言板</title>
12 </head>
13 <body>
14 <logic:iterate name="ListForm" property="topics" id="topic">
15 <table>
16 <tr>
17 <td>
18 <table>
19 <tr>
20 <td>
21 <bean:write name="topic" property="post.subject"/> 留言者：<bean:write name="topic" property="post.name" /> 留言日：<bean:write name="topic" property="post.date" format="yyyy/MM/dd(E) HH:mm" /> No.<bean:write name="topic" property="post.id" />
22 </td>
23 </tr>
24 </table>
25 <table>
26 <tr>
27 <td>
28 <img src="<bean:write name='topic' property='post.icon'/>" alt=""/>
29 </td>
30 <td>
31 <font color="<bean:write name='topic' property='post.font'/>">
32 <bean:write name="topic" property="post.content" filter="false" />
33 </font>
34 </td>
35 </tr>
36 </table>
37 <logic:iterate name="topic" property="replies" id="reply">
38 <hr>
39 <table>
40 <tr>
41 <td><bean:write name="reply" property="subject"/><bean:write name="reply" property="name"/> - <bean:write name="reply" property="date" format="yyyy /MM/dd(E) HH:mm" /> No.<bean:write name="reply" property="id"/></td>
42 </tr>
43 </table>
44 <table>
45 <tr>
46 <td>
47 <img src="<bean:write name='reply' property='icon' />" alt=""/>
48 </td>
49 <td><font color="<bean:write name='reply' property='font'/>"><bean:write name="reply" property="content" filter="false"/></font></td>
50 </tr>
51 </table>
52 </logic:iterate>
53 <hr>
54 </td>
55 </tr>
56 </table>
57 </logic:iterate>
58 </body>
59 </html>
60
可以注意到在網頁里面，多了一個<logic:iterator>的tag，這個標記是對內部指定的數據就行遍歷(循環)。
- 根據這個jsp網頁，對應的ActionForm bean很簡單
ListForm.java中只需要一個字段，用于收集所有的留言
public class ListForm extends org.apache.struts.action.ActionForm {
private List topics;
public List getTopics() {
return topics;
}
public void setTopics(List topics) {
this.topics = topics;
}
}
- 創建對應的Action class。
1 public class ListAction extends org.apache.struts.action.Action {
2
3 /* forward name="success" path="" */
4 private static final String SUCCESS = "bbs.list";
5
6 /**
7 * This is the action called from the Struts framework.
8 * @param mapping The ActionMapping used to select this instance.
9 * @param form The optional ActionForm bean for this request.
10 * @param request The HTTP Request we are processing.
11 * @param response The HTTP Response we are processing.
12 * @throws java.lang.Exception
13 * @return
14 */
15 @Override
16 public ActionForward execute(ActionMapping mapping, ActionForm form,
17 HttpServletRequest request, HttpServletResponse response) {
18 ListForm f = (ListForm) form;
19 String sql;
20 QueryRunner qr = DbHelper.getQueryRunner();
21 List list = new ArrayList();
22 List posts = null;
23
24 // default replyId = -1 means this post is the topic
25 sql = "select g.id as id, g.name as name,subject,content,email,url,replyId,iconId,i.src as icon,lastReplyTime,date,font from guestbook g, icon i " + " where replyId = -1 and i.id = iconId order by lastReplyTime desc ";
26 try {
27 posts = (List) qr.query(sql, new BeanListHandler(Post.class));
28 } catch (SQLException ex) {
29 Logger.getLogger(ListAction.class.getName()).log(Level.SEVERE, null, ex);
30 }
31 //according to topics.id, querying all related post;
32 for (int i = 0; i < posts.size(); i++) {
33 Post post = (Post) posts.get(i);
34 List replies = null;
35 sql = "select g.id as id, g.name as name, subject,content,email,url,replyId,iconId,i.src as icon,lastReplyTime,date,font from guestbook g, icon i " + " where replyId = " + post.getId() + " and i.id = iconId order by id";
36 try {
37 replies = (List) qr.query(sql, new BeanListHandler(Post.class));
38 } catch (SQLException ex) {
39 Logger.getLogger(ListAction.class.getName()).log(Level.SEVERE, null, ex);
40 }
41 list.add(new Topic(post,replies));
42 }
43 f.setTopics(list);
44 return mapping.findForward(SUCCESS);
45 }
46 }
27行先查詢主題留言，32-42行對每個主題留言查詢與之相關的回復，41行 創建一個topic對象，添加進集合；43行對listForm的topics賦值。
- 相關的struts-config.xml的聲明如下
1 <form-beans>
2 <form-bean name="ListForm" type="com.bbs.struts.form.ListForm"/>
3 <form-bean name="NewForm" type="com.bbs.struts.form.NewForm"/>
4
5 </form-beans>
6
7
8 <global-forwards>
9 <forward name="bbs.post" path="/result.jsp"/>
10 <forward name="bbs.list" path="/display.jsp"/>
11 <forward name="welcome" path="/Welcome.do"/>
12 </global-forwards>
13
14 <action-mappings>
15 <action input="/display.jsp" name="ListForm" path="/list" scope="request" type="com.bbs.struts.action.ListAction" validate="false"/>
16 <action input="/post.jsp" name="NewForm" path="/post" scope="request" type="com.bbs.struts.action.PostAction"/>
17 <action path="/Welcome" forward="/welcomeStruts.jsp"/>
18 </action-mappings>
- 測試
deploy的應用，瀏覽器中輸入http://localhost:8080/BBS/list.do，測試正確（暫時不會有回復出現，下一節我們將討論留言回復的問題）。