一个实用的JSP分页代码

湛蓝之海

有热心网友回复：
str += " 转到<select name='page' onChange=\"window.location.href='" + fileName + temp + "cur_page='+this.options[this.selectedIndex].value\">";
已经试过了，没问题
1.以下是实现分页的类PageResultSet

package page.bean; 
import java.util.*; 
public class PageResultSet { 
/** 
* 分页数据 
*/ 
private Collection data = null; 
/** 
* 当前页 
*/ 
private int curPage; 
/** 
* 每页显示的记录数 
*/ 
private int pageSize; 
/** 
* 记录行数 
*/ 
private int rowsCount; 
/** 
* 页数 
*/ 
private int pageCount; 
public PageResultSet(Collection data) { 
this.data = data; 
this.curPage = 1; 
this.pageSize = 10; 
this.rowsCount = data.size(); 
this.pageCount = (int) Math.ceil((double) rowsCount / pageSize); 
} 
public PageResultSet(Collection data, int curPage) { 
this.data = data; 
this.curPage = curPage; 
this.pageSize = 10; 
this.rowsCount = data.size(); 
this.pageCount = (int) Math.ceil((double) rowsCount / pageSize); 
} 
public PageResultSet(Collection data, int curPage, int pageSize) { 
this.data = data; 
this.curPage = curPage; 
this.pageSize = pageSize; 
this.rowsCount = data.size(); 
this.pageCount = (int) Math.ceil((double) rowsCount / pageSize); 
} 
/** 
* getCurPage:返回当前的页数 
* 
* @return int 
*/ 
public int getCurPage() { 
return curPage; 
} 
/** 
* getPageSize：返回分页大小 
* 
* @return int 
*/ 
public int getPageSize() { 
return pageSize; 
} 
/** 
* getRowsCount：返回总记录行数 
* 
* @return int 
*/ 
public int getRowsCount() { 
return rowsCount; 
} 
/** 
* getPageCount：返回总页数 
* 
* @return int 
*/ 
public int getPageCount() { 
return pageCount; 
} 
/** 
* 第一页 
* 
* @return int 
*/ 
public int first() { 
return 1; 
} 
/** 
* 最后一页 
* 
* @return int 
*/ 
public int last() { 
return pageCount; 
} 
/** 
* 上一页 
* 
* @return int 
*/ 
public int previous() { 
return (curPage - 1 < 1) ? 1 : curPage - 1; 
} 
/** 
* 下一页 
* 
* @return int 
*/ 
public int next() { 
return (curPage + 1 > pageCount) ? pageCount : curPage + 1; 
} 
/** 
* 第一页 
* 
* @return boolean 
*/ 
public boolean isFirst() { 
return (curPage == 1) ? true : false; 
} 
/** 
* 最后一页 
* 
* @return boolean 
*/ 
public boolean isLast() { 
return (curPage == pageCount) ? true : false; 
} 
/** * 获取当前页数据 
* 
* @return Collection 
*/ 
public Collection getData() { 
Collection curData = null; 
if (data != null) { 
int start = (curPage - 1) * pageSize; 
int end = 0; 
if (start + pageSize > rowsCount) 
end = rowsCount; 
else 
end = start + pageSize; 
ArrayList arrayCurData = new ArrayList(); 
ArrayList arrayData = null; 
Vector vectorCurData = new Vector(); 
Vector vectorData = null; 
boolean isArray = true; 
if (data instanceof ArrayList) { 
arrayData = (ArrayList) data; 
isArray = true; 
} else if (data instanceof Vector) { 
vectorData = (Vector) data; 
isArray = false; 
} 
for (int i = start; i < end; i++) { 
if (isArray) { 
arrayCurData.add(arrayData.get(i)); 
} else { 
vectorData.add(vectorData.elementAt(i)); 
} 
} 
if (isArray) { 
curData = (Collection) arrayCurData; 
} else { 
curData = (Collection) vectorCurData; 
} 
} 
return curData; 
} 
/** 
* 获取工具条 
* 
* @return String 
*/ 
public String getToolBar(String fileName) { 
String temp = ""; 
if (fileName.indexOf("?") == -1) { 
temp = "?"; 
} else { 
temp = "&"; 
} 
String str = "<form method='post' name='frmPage' action='" + fileName + "'>"; 
str += "<p align='center'>"; 
if (isFirst()) 
str += "首页 上一页 "; 
else { 
str += "<a href='" + fileName + temp + "cur_page=1'>首页</a> "; 
str += "<a href='" + fileName + temp + "cur_page=" + (curPage - 1) + "'>上一页</a> "; 
} 
if (isLast()) 
str += "下一页 尾页 "; 
else { 
str += "<a href='" + fileName + temp + "cur_page=" + (curPage + 1) + "'>下一页</a> "; 
str += "<a href='" + fileName + temp + "cur_page=" + pageCount + "'>尾页</a> "; 
} 
str += " 共<b>" + rowsCount + "</b>条记录 "; 
str += " 转到<select name='page' onChange="location='" + fileName 
+ temp + "cur_page='+this.options[this.selectedIndex].value">"; 
for (int i = 1; i <= pageCount; i++) { 
if (i == curPage) 
str += "<option value='" + i + "' selected>第" + i + "页</option>"; 
else 
str += "<option value='" + i + "'>第" + i + "页</option>"; 
} 
str += "</select></p></form>"; 
return str; 
} 
}

2.一下是Action

/* 
* Generated by MyEclipse Struts 
* Template path: templates/java/JavaClass.vtl 
*/ 
package struts.action; 
import java.util.Collection; 
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 page.bean.DatabaseConn; 
import page.bean.PageResultSet; 
import page.bean.ContactBO; 
import struts.form.LoginForm; 
/** 
* MyEclipse Struts 
* Creation date: 04-02-2008 
* 
* XDoclet definition: 
* @struts.action path="/login" name="loginForm" input="/login.jsp" scope="request" validate="true" 
* @struts.action-forward name="sss" path="/index.jsp" 
*/ 
public class LoginAction extends Action { 
/* 
* Generated Methods 
*/ 
/** 
* Method execute 
* @param mapping 
* @param form 
* @param request 
* @param response 
* @return ActionForward 
*/ 
public ActionForward execute(ActionMapping mapping, ActionForm form, 
HttpServletRequest request, HttpServletResponse response) { 
LoginForm loginForm = (LoginForm) form; 
ContactBO userBO=new ContactBO(); 
//先从业务处理逻辑类中取出数据(ArrayList或Vector格式) 
Collection data; 
try { 
data = userBO.findContact(DatabaseConn.getConnection()); 
//再得到当前页curPage和每页记录数pageSize 
//int curPage = Integer.parseInt((String)request.getParameter("cur_page")); 
int curPage = 1; 
String cur = request.getParameter("cur_page"); 
System.out.println("--------------: "+cur); 
if(cur!=null && cur !=""){ 
curPage = new Integer(cur).intValue(); 
} 
int pageSize=10; 
//然后生成PageResultSet对象 
PageResultSet dataList = new PageResultSet(data, curPage, pageSize); 
request.setAttribute("usersList", dataList); 
return mapping.findForward("sss"); 
} catch (Exception e) { 
e.printStackTrace(); 
return mapping.getInputForward(); 
} 
} 
}

3.以下是显示分页的页面

<%@ page language="java" import="java.util.*,page.bean.Contact,page.bean.PageResultSet" 
pageEncoding="gb2312"%> 
<% 
String path = request.getContextPath(); 
String basePath = request.getScheme() + "://" 
+ request.getServerName() + ":" + request.getServerPort() 
+ path + "/"; 
%> 
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"> 
<html> 
<head> 
<base href="<%=basePath%>"> 
<title>My JSP 'index.jsp' starting page</title> 
<meta http-equiv="pragma" content="no-cache"> 
<meta http-equiv="cache-control" content="no-cache"> 
<meta http-equiv="expires" content="0"> 
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> 
<meta http-equiv="description" content="This is my page"> 
<!-- 
<link rel="stylesheet" type="text/css" href="styles.css"> 
--> 
</head> 
<body> 
<table border="1"> 
<% 
PageResultSet pageResultSet = (PageResultSet) request.getAttribute("usersList"); 
ArrayList usersList = (ArrayList) pageResultSet.getData(); 
for (int i = 0; i < usersList.size(); i++) { 
Contact co = (Contact) usersList.get(i); 
%> 
<tr> 
<td> 
<%=co.getId() %> 
</td> 
<td> 
<a href="login.do?id=<%=co.getId()%>"><%=co.getUsername()%></a> 
</td> 
<td> 
<%=co.getMobile() %> 
</td> 
<td> 
<%=co.getMail() %> 
</td> 
<td> 
<%=co.getPhone() %> 
</td> 
<td> 
<%=co.getMem() %> 
</td> 
<td> 
<%=co.getLastcontact() %> 
</td> 
</tr> 
<% 
} 
%> 
</table> 
<!-- 显示分页工具栏 --> 
<%=pageResultSet.getToolBar("login.do")%> 
</body> 
</html>