如何在Struts中实现分页显示数据

如何在Struts中实现分页显示数据

PageData类代码：

  1import java.util.Collection;
  2
  3/**//**
  4 * <p>Title: </p>
  5 * <p>Description: </p>
  6 * <p>Copyright: Copyright (c) 2003</p>
  7 * <p>Company: </p>
  8 * @author George Hill
  9 * @version 1.0
 10 */
 11
 12public class PageData {
 13
 14  /**//**
 15   * 每页显示的数据行数
 16   */
 17  public final static int NUMBER_PER_PAGE = 15;
 18
 19  /**//**
 20   * 保存页面显示的数据集合
 21   */
 22  protected Collection list;
 23
 24  /**//**
 25   * 当前页数
 26   */
 27  protected int page;
 28
 29  /**//**
 30   * 最大页数
 31   */
 32  protected int maxPage;
 33
 34  /**//**
 35   * 无参构造方法
 36   */
 37  public PageData() {}
 38
 39  /**//**
 40   * 构造方法
 41   * @param list 数据集
 42   * @param page 当前页数
 43   * @param maxPage 最大页数
 44   */
 45  public PageData(Collection list, int page, int maxPage) {
 46    this.list = list;
 47    this.page = page;
 48    this.maxPage = maxPage;
 49  }
 50
 51  /**//**
 52   * 获得数据集合
 53   * @return 数据集合
 54   */
 55  public Collection getList() {
 56    return this.list;
 57  }
 58
 59  /**//**
 60   * 设置数据集合
 61   * @param list 新的数据集合
 62   */
 63  public void setList(Collection list) {
 64    this.list = list;
 65  }
 66
 67  /**//**
 68   * 获得当前页数
 69   * @return 当前页数
 70   */
 71  public int getPage() {
 72    return this.page;
 73  }
 74
 75  /**//**
 76   * 获得上页页数
 77   * @return 上页页数
 78   */
 79  public int getPrePage() {
 80    int prePage = page - 1;
 81
 82    if (prePage <= 0)
 83      prePage = 1;
 84
 85    return prePage;
 86  }
 87
 88  /**//**
 89   * 获得下页页数
 90   * @return 下页页数
 91   */
 92  public int getNextPage() {
 93    int next = page + 1;
 94
 95    if (next > maxPage)
 96      next = maxPage;
 97
 98    return next;
 99  }
100
101  /**//**
102   * 设置当前页数
103   * @param page 当前页数新值
104   */
105  public void setPage(int page) {
106    this.page = page;
107  }
108
109  /**//**
110   * 获得最大页数
111   * @return 最大页数
112   */
113  public int getMaxPage() {
114    return this.maxPage;
115  }
116
117  /**//**
118   * 设置最大页数
119   * @param maxPage 最大页数新值
120   */
121  public void setMaxPage(int maxPage) {
122    this.maxPage = maxPage;
123  }
124
125  /**//**
126   * 获得首页标识
127   * @return 首页标识
128   */
129  public boolean isFirstPage() {
130    if (this.page <= 1)
131      return true;
132
133    return false;
134  }
135
136  /**//**
137   * 获得末页标识
138   * @return 末页标识
139   */
140  public boolean isLastPage() {
141    if (this.page >= this.maxPage)
142      return true;
143
144    return false;
145  }
146}
147
      TurnPageForm类代码：

  1import javax.servlet.http.*;
  2import org.apache.struts.action.*;
  3
  4/**//**
  5 * <p>Title: </p>
  6 * <p>Description: </p>
  7 * <p>Copyright: Copyright (c) 2003</p>
  8 * <p>Company: </p>
  9 * @author George Hill
 10 * @version 1.0
 11 */
 12
 13public class TurnPageForm extends ActionForm{
 14
 15  /**//**
 16   * 要跳转的页码
 17   */
 18  protected int page;
 19
 20  /**//**
 21   * 跳转按钮
 22   */
 23  protected String turn;
 24
 25  /**//**
 26   * 首页按钮
 27   */
 28  protected String first;
 29
 30  /**//**
 31   * 上一页按钮
 32   */
 33  protected String preview;
 34
 35  /**//**
 36   * 下一页按钮
 37   */
 38  protected String next;
 39
 40  /**//**
 41   * 末页按钮
 42   */
 43  protected String last;
 44
 45  /**//**
 46   * 跳转地址
 47   */
 48  protected String url;
 49
 50  /**//**
 51   * 当前页码
 52   */
 53  protected int currentPage;
 54
 55  /**//**
 56   * 最大页码
 57   */
 58  protected int maxPage;
 59
 60  /**//**
 61   * 获得跳转页码
 62   * @return 跳转页码
 63   */
 64  public int getPage() {
 65    return this.page;
 66  }
 67
 68  /**//**
 69   * 设置跳转页码
 70   * @param page 跳转页码值
 71   */
 72  public void setPage(int page) {
 73    this.page = page;
 74  }
 75
 76  /**//**
 77   * 获得跳转按钮值
 78   * @return 跳转按钮值
 79   */
 80  public String getTurn() {
 81    return this.turn;
 82  }
 83
 84  /**//**
 85   * 设置跳转按钮值
 86   * @param turn 跳转按钮值
 87   */
 88  public void setTurn(String turn) {
 89    this.turn = turn;
 90  }
 91
 92  /**//**
 93   * 获得首页按钮值
 94   * @return 首页按钮值
 95   */
 96  public String getFirst() {
 97    return this.first;
 98  }
 99
100  /**//**
101   * 设置首页按钮值
102   * @param first 首页按钮值
103   */
104  public void setFirst(String first) {
105    this.first = first;
106  }
107
108  /**//**
109   * 获得上一页按钮值
110   * @return 上一页按钮值
111   */
112  public String getPreview() {
113    return this.preview;
114  }
115
116  /**//**
117   * 设置上一页按钮值
118   * @param preview 上一页按钮值
119   */
120  public void setPreview(String preview) {
121    this.preview = preview;
122  }
123
124  /**//**
125   * 获得下一页按钮值
126   * @return 下一页按钮值
127   */
128  public String getNext() {
129    return this.next;
130  }
131
132  /**//**
133   * 设置下一页按钮值
134   * @param next 下一页按钮值
135   */
136  public void setNext(String next) {
137    this.next = next;
138  }
139
140  /**//**
141   * 获得末页按钮值
142   * @return 末页按钮值
143   */
144  public String getLast() {
145    return this.last;
146  }
147
148  /**//**
149   * 设置末页按钮值
150   * @param last 末页按钮值
151   */
152  public void setLast(String last) {
153    this.last = last;
154  }
155
156  /**//**
157   * 获得跳转地址
158   * @return 跳转地址
159   */
160  public String getUrl() {
161    return this.url;
162  }
163
164  /**//**
165   * 设置跳转地址
166   * @param url 跳转地址
167   */
168  public void setUrl(String url) {
169    this.url = url;
170  }
171
172  /**//**
173   * 获得当前页码
174   * @return 当前页码
175   */
176  public int getCurrentPage() {
177    return this.currentPage;
178  }
179
180  /**//**
181   * 设置当前页码
182   * @param page 当前页码值
183   */
184  public void setCurrentPage(int page) {
185    this.currentPage = page;
186  }
187
188  /**//**
189   * 获得最大页码
190   * @return 最大页码
191   */
192  public int getMaxPage() {
193    return this.maxPage;
194  }
195
196  /**//**
197   * 设置最大页码
198   * @param page 最大页码
199   */
200  public void setMaxPage(int page) {
201    this.maxPage = page;
202  }
203
204  /**//**
205   * 重置属性
206   * @param mapping action映射
207   * @param request HTTP请求
208   */
209  public void reset(ActionMapping mapping, HttpServletRequest request) {
210    this.page = 0;
211    this.turn = null;
212    this.first = null;
213    this.preview = null;
214    this.next = null;
215    this.last = null;
216    this.url = null;
217    this.currentPage = 0;
218    this.maxPage = 0;
219  }
220
221}
222
      TurnPageAction代码：

 1import java.io.*;
 2import javax.servlet.*;
 3import javax.servlet.http.*;
 4
 5import org.apache.struts.action.*;
 6
 7import xxx.TurnPageForm;
 8
 9/**//**
10 * <p>Title: </p>
11 * <p>Description: </p>
12 * <p>Copyright: Copyright (c) 2003</p>
13 * <p>Company: </p>
14 * @author George Hill
15 * @version 1.0
16 */
17
18public class TurnPageAction extends Action {
19
20  /**//**
21   * 执行用户的跳转页面请求
22   * @param mapping 转发映射表
23   * @param form 请求的ActionForm Bean
24   * @param request 用户请求
25   * @param response 用户应答
26   * @return 成功或者失败的转发
27   * @throws IOException IO例外
28   * @throws ServletException Servlet例外
29   */
30  public ActionForward execute(ActionMapping mapping, ActionForm form,
31                               HttpServletRequest request,
32                               HttpServletResponse response) throws IOException,
33      ServletException {
34    if (form instanceof TurnPageForm) {
35      TurnPageForm tform = (TurnPageForm) form;
36      int page = 0;
37      String url = null;
38
39      if (tform.getTurn() != null) {
40        page = tform.getPage();
41      } else if (tform.getFirst() != null) {
42        page = 1;
43      } else if (tform.getPreview() != null) {
44        page = tform.getCurrentPage() - 1;
45      } else if (tform.getNext() != null) {
46        page = tform.getCurrentPage() + 1;
47      } else if (tform.getLast() != null) {
48        page = tform.getMaxPage();
49      }
50
51      if (page < 1) {
52        page = 1;
53      } else if (page > tform.getMaxPage()) {
54        page = tform.getMaxPage();
55      }
56      if (tform.getUrl().indexOf("?") == -1) {
57        url = tform.getUrl() + "?page=" + page;
58      } else {
59        url = tform.getUrl() + "&page=" + page;
60      }
61      return new ActionForward(url);
62    }
63
64    return mapping.findForward("error");
65  }
66}
67
      struts-config.xml的相关片断：

 1<?xml version="1.0" encoding="UTF-8"?>
 2<!DOCTYPE struts-config PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 1.1//EN" "http://jakarta.apache.org/struts/dtds/struts-config_1_1.dtd">
 3<struts-config>
 4  <form-beans>
 5
 6    <form-bean name="turnPageForm" type="xxx.TurnPageForm" />
 7
 8  </form-bean>
 9  <action-mappings>
10
11    <action name="turnPageForm" path="/turnPage" scope="request" type="xxx.TurnPageAction" />
12  </action-mappings>
13</struts-config>

action类

1import java.util.List;
 2import javax.servlet.http.*;
 3
 4import org.apache.struts.action.*;
 5
 6import xxx.Administrator;
 7import xxx.TurnPageForm;
 8import xxx.PageData;
 9
10/**//**
11 * <p>Title: </p>
12 *
13 * <p>Description: </p>
14 *
15 * <p>Copyright: Copyright (c) 2003</p>
16 *
17 * <p>Company: </p>
18 *
19 * @author George Hill
20 * @version 1.0
21 */
22
23public class AdminListAction extends Action {
24
25  private static final int NUMBER = 15;
26
27  /**//**
28   * 执行管理员列表操作
29   * @param mapping ActionMapping
30   * @param form ActionForm
31   * @param request HttpServletRequest
32   * @param response HttpServletResponse
33   * @throws Exception
34   * @return ActionForward
35   */
36  public ActionForward execute(ActionMapping mapping, ActionForm form,
37                               HttpServletRequest request,
38                               HttpServletResponse response) throws Exception {
39    HttpSession session = request.getSession();
40
41    //获取页码
42    String pageStr = request.getParameter("page");
43    if (pageStr == null)
44      pageStr = String.valueOf(session.getAttribute("page"));
45    else
46      session.setAttribute("page", pageStr);
47    int page = 1;
48    try {
49      page = Integer.parseInt(pageStr);
50    } catch (NumberFormatException nfe) {
51    }
52
53    //获得总记录数
54    int count = Administrator.countAllAdministrators();
55    int maxPage = count / NUMBER;
56    if (count % NUMBER != 0)
57      maxPage++;
58
59    //获得列表
60    List list = Administrator.getAdministrators(NUMBER, (page - 1) * NUMBER);
61
62    if (count != 0 && list == null)
63      list = Administrator.getAdministrators(NUMBER, 0);
64
65    if (list != null) {
66      PageData data = new PageData(list, page, maxPage);
67
68      request.setAttribute("admins", data);
69    }
70
71    //分页部分
72    TurnPageForm tform = new TurnPageForm();
73    tform.setCurrentPage(page);
74    tform.setMaxPage(maxPage);
75    request.setAttribute("turnPageForm", tform);
76
77    return mapping.findForward("list");
78  }
79}
80
jsp显示
1    <logic:present name="admins">
 2      <table width="90%" border="0" align="center" cellpadding="0" cellspacing="1" class="table6">
 3        <tr align="center" class="table4">
 4          <td width="10%" height="18" align="center" nowrap class="head1"><bean:message key="list.index"/></td>
 5          <td width="20%" class="head1" align="center" nowrap><bean:message key="admin.account"/></td>
 6          <td width="30%" class="head1" align="center" nowrap><bean:message key="admin.name"/></td>
 7          <td width="10%" class="head1" align="center" nowrap><bean:message key="admin.status"/></td>
 8          <td width="30%" class="head1" align="center" nowrap><bean:message key="list.action"/></td>
 9        </tr>
10      <logic:iterate name="admins" property="list" id="entry" indexId="index">
11        <tr class="table5" onmouseover="changeColor(this, '#99CCFF')" onmouseout="changeColor(this, '#F2F3F4')">
12          <td align="center" nowrap><bean:write name="index"/></td>
13          <td align="center" nowrap><bean:write name="entry" property="account"/></td>
14          <td align="center" nowrap><bean:write name="entry" property="name"/></td>
15        <logic:equal name="entry" property="status" value="true">
16          <td align="center" nowrap><bean:message key="status.enable"/></td>
17          <td align="center" nowrap>
18            <html:link page="/disableAdmin.do?status=false" paramId="account" paramName="entry" paramProperty="account" onclick="return MM_popupDisableMsg()">
19              <font color="red"><bean:message key="status.disable"/></font>
20            </html:link>
21            <html:link page="/modifyAdmin.do?action=link" paramId="account" paramName="entry" paramProperty="account">
22              <bean:message key="action.modify"/>
23            </html:link>
24            <html:link action="/deleteAdmin" paramId="account" paramName="entry" paramProperty="account" onclick="return MM_popupDelMsg()">
25              <font color="red"><bean:message key="action.delete"/></font>
26            </html:link>
27          </td>
28        </logic:equal>
29        <logic:equal name="entry" property="status" value="false">
30          <td align="center" nowrap><font color="red"><bean:message key="status.disable"/></font></td>
31          <td align="center" nowrap>
32            <html:link page="/enableAdmin.do?status=true" paramId="account" paramName="entry" paramProperty="account">
33              <bean:message key="status.enable"/>
34            </html:link>
35            <html:link page="/modifyAdmin.do?action=link" paramId="account" paramName="entry" paramProperty="account">
36              <bean:message key="action.modify"/>
37            </html:link>
38            <html:link action="/deleteAdmin" paramId="account" paramName="entry" paramProperty="account" onclick="return MM_popupDelMsg()">
39              <font color="red"><bean:message key="action.delete"/></font>
40            </html:link>
41          </td>
42        </logic:equal>
43        </tr>
44      </logic:iterate>
45      </table>
46      <table width="90%" border="0" align="center" cellpadding="3" cellspacing="0">
47        <tr>
48          <td align="left"></td>
49        <html:form action="/turnPage" method="POST">
50          <td align="right" nowrap>
51            <html:hidden property="url" value="/listAdmin.do"/>
52            <html:hidden property="currentPage"/>
53            <html:hidden property="maxPage"/>
54            <bean:message key="page.the"/>
55            <bean:write name="admins" property="page"/>
56            <bean:message key="page.page"/>/
57            <bean:message key="page.all"/><bean:write name="admins" property="maxPage"/><bean:message key="page.page"/>
58            <bean:message key="page.turn"/>
59          <logic:equal name="admins" property="maxPage" value="1">
60            <html:text property="page" styleClass="input_log" styleId="page" size="3" value="" disabled="true"/>
61            <html:submit property="turn" styleClass="t_input" styleId="turn" value="GO" disabled="true"/>
62          </logic:equal>
63          <logic:notEqual name="admins" property="maxPage" value="1">
64            <html:text property="page" styleClass="input_log" styleId="page" size="3" value=""/>
65            <html:submit property="turn" styleClass="t_input" styleId="turn" value="GO"/>
66          </logic:notEqual>
67          <logic:equal name="admins" property="firstPage" value="true">
68            <html:submit property="first" styleClass="t_input" styleId="first" disabled="true"><bean:message key="page.first"/></html:submit>
69            <html:submit property="preview" styleClass="t_input" styleId="preview" disabled="true"><bean:message key="page.previous"/></html:submit>
70          </logic:equal>
71          <logic:notEqual name="admins" property="firstPage" value="true">
72            <html:submit property="first" styleClass="t_input" styleId="first"><bean:message key="page.first"/></html:submit>
73            <html:submit property="preview" styleClass="t_input" styleId="preview"><bean:message key="page.previous"/></html:submit>
74          </logic:notEqual>
75          <logic:equal name="admins" property="lastPage" value="true">
76            <html:submit property="next" styleClass="t_input" styleId="next" disabled="true"><bean:message key="page.next"/></html:submit>
77            <html:submit property="last" styleClass="t_input" styleId="last" disabled="true"><bean:message key="page.last"/></html:submit>
78          </logic:equal>
79          <logic:notEqual name="admins" property="lastPage" value="true">
80            <html:submit property="next" styleClass="t_input" styleId="next"><bean:message key="page.next"/></html:submit>
81            <html:submit property="last" styleClass="t_input" styleId="last"><bean:message key="page.last"/></html:submit>
82          </logic:notEqual>
83          </td>
84        </html:form>
85        </tr>
86      </table>
87    </logic:present>