先是一个page的bean：
Java代码
package com.leatherstore.other;
public class Page {
/** 是否有上一页 */
private boolean hasPrePage;
/** 是否有下一页 */
private boolean hasNextPage;
/** 每页的数量 */
private int everyPage;
/** 总页数 */
private int totalPage;
/** 当前页*/
private int currentPage;
/** 起始点 */
private int beginIndex;
/** 总记录数*/
private int totalCount;
/**
* @return totalCount
*/
public int getTotalCount() {
return totalCount;
}
/**
* @param totalCount 要设置的 totalCount
*/
public void setTotalCount(int totalCount) {
this.totalCount = totalCount;
}
/** The default constructor */
public Page(){
}
/** construct the page by everyPage
* @param everyPage
* */
public Page(int everyPage){
this.everyPage = everyPage;
}
/** The whole constructor */
public Page(boolean hasPrePage, boolean hasNextPage,
int everyPage, int totalPage,
int currentPage, int beginIndex,int totalCount) {
this.hasPrePage = hasPrePage;
this.hasNextPage = hasNextPage;
this.everyPage = everyPage;
this.totalPage = totalPage;
this.currentPage = currentPage;
this.beginIndex = beginIndex;
this.totalCount = totalCount;
}
/**
* @return
* Returns the beginIndex.
*/
public int getBeginIndex() {
return beginIndex;
}
/**
* @param beginIndex
* The beginIndex to set.
*/
public void setBeginIndex(int beginIndex) {
this.beginIndex = beginIndex;
}
/**
* @return
* Returns the currentPage.
*/
public int getCurrentPage() {
return currentPage;
}
/**
* @param currentPage
* The currentPage to set.
*/
public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}
/**
* @return
* Returns the everyPage.
*/
public int getEveryPage() {
return everyPage;
}
/**
* @param everyPage
* The everyPage to set.
*/
public void setEveryPage(int everyPage) {
this.everyPage = everyPage;
}
/**
* @return
* Returns the hasNextPage.
*/
public boolean getHasNextPage() {
return hasNextPage;
}
/**
* @param hasNextPage
* The hasNextPage to set.
*/
public void setHasNextPage(boolean hasNextPage) {
this.hasNextPage = hasNextPage;
}
/**
* @return
* Returns the hasPrePage.
*/
public boolean getHasPrePage() {
return hasPrePage;
}
/**
* @param hasPrePage
* The hasPrePage to set.
*/
public void setHasPrePage(boolean hasPrePage) {
this.hasPrePage = hasPrePage;
}
/**
* @return Returns the totalPage.
*
*/
public int getTotalPage() {
return totalPage;
}
/**
* @param totalPage
* The totalPage to set.
*/
public void setTotalPage(int totalPage) {
this.totalPage = totalPage;
}
}
然后构建一个page的工厂PageUtil：
package com.leatherstore.other;
public class PageUtil {
/**
* Use the origin page to create a new page
*
* @param page
* @param totalRecords
* @return
*/
public static Page createPage(Page page, int totalRecords) {
return createPage(page.getEveryPage(), page.getCurrentPage(),
totalRecords);
}
/**
* the basic page utils not including exception handler
*
* @param everyPage
* @param currentPage
* @param totalRecords
* @return page
*/
public static Page createPage(int everyPage, int currentPage,
int totalRecords) {
everyPage = getEveryPage(everyPage);
currentPage = getCurrentPage(currentPage);
int beginIndex = getBeginIndex(everyPage, currentPage);
int totalPage = getTotalPage(everyPage, totalRecords);
boolean hasNextPage = hasNextPage(currentPage, totalPage);
boolean hasPrePage = hasPrePage(currentPage);
return new Page(hasPrePage, hasNextPage, everyPage, totalPage,
currentPage, beginIndex, totalRecords);
}
private static int getEveryPage(int everyPage) {
return everyPage == 0 ? 10 : everyPage;
}
private static int getCurrentPage(int currentPage) {
return currentPage == 0 ? 1 : currentPage;
}
private static int getBeginIndex(int everyPage, int currentPage) {
return (currentPage - 1) * everyPage;
}
private static int getTotalPage(int everyPage, int totalRecords) {
int totalPage = 0;
if (totalRecords % everyPage == 0)
totalPage = totalRecords / everyPage;
else
totalPage = totalRecords / everyPage + 1;
return totalPage;
}
private static boolean hasPrePage(int currentPage) {
return currentPage == 1 ? false : true;
}
private static boolean hasNextPage(int currentPage, int totalPage) {
return currentPage == totalPage || totalPage == 0 ? false : true;
}
}
然后建一个专用的bean：
package com.leatherstore.hibernate.domain;
import java.util.List;
import com.leatherstore.other.Page;
public class Result {
private Page page; //分页信息
private List content; //每页显示的集合
/**
* The default constructor
*/
public Result() {
super();
}
/**
* The constructor using fields
*
* @param page
* @param content
*/
public Result(Page page, List content) {
this.page = page;
this.content = content;
}
/**
* @return Returns the content.
*/
public List getContent() {
return content;
}
/**
* @return Returns the page.
*/
public Page getPage() {
return page;
}
/**
* @param content
* The content to set.
*/
public void setContent(List content) {
this.content = content;
}
/**
* @param page
* The page to set.
*/
public void setPage(Page page) {
this.page = page;
}
}
然后在数据访问层写两个方法：
ProductDAO：
public List getProductByPage(Page page);
public int getProductCount(); //返回数据的总数
ProductDAO的接口实现ProductDAOImpl：
//为了在spring里统一编程风格：我用的回调的方法
public List getProductByPage(final Page page) {
return this.getHibernateTemplate().executeFind(new HibernateCallback(){
public Object doInHibernate(Session session) throws HibernateException, SQLException {
Query query=session.createQuery("from Productinfo");
query.setFirstResult(page.getBeginIndex()); //hibernate分页的精髓 呵呵
query.setMaxResults(page.getEveryPage());
return query.list();
}
});
}
public int getProductCount() {
List list=this.getHibernateTemplate().find("select count(*) from Productinfo");
return ((Integer)list.iterator().next()).intValue();
}
然后是业务层：
IProduct：
public Result listProduct(Page page);
然后IProduct接口的实现：IProductImpl：
private ProductDAO productDAO;
public void setProductDAO(ProductDAO productDAO){
this.productDAO=productDAO;
}
public Result listProduct(Page page) {
int totalRecords = this.productDAO.getProductCount();
page = PageUtil.createPage(page, totalRecords);
List products = this.productDAO.getProductByPage(page);
return new Result(page, products);
}
然后再代理层：
ProductProxy：
IProduct pro=(IProduct)AppContext.getInstance().getappcontext().getBean("productServicewithTran");
public Result productlist(Page page){
try{
return pro.listProduct(page);
}catch(DataAccessException ex){
ex.printStackTrace();
return null;
}
}
呵呵 终于到productAction啦
显示前方法的代码
Page page = new Page(); //实例化一个page对象
page.setEveryPage(10); //设置每页显示的条数
page.setCurrentPage(1); //为第一页
Result result = pdp.productlist(page);
request.setAttribute("page", pageinfo);
request.setAttribute("productlist", list);
return mapping.findForward("showProduct");
接着就是jsp页面了
<logic:iterate id="product" name="productlist">
//中间迭代所要显示的数据
</logic:iterate>
<tr>
<td width="80" height="30"> </td>
<logic:equal value="true" name="page" property="hasPrePage">
<td width="150" height="30"><div align="right"><a
href="../product.do?method=showProductByTag&index=first&
msg=${msg }">首页</a></div></td>
<td width="80" height="30"><div align="center"><a
href="../product.do?method=showProductByTag&index=prew&pageno=${page.currentPage
-1}&msg=${msg }">上一页</a></div></td>
</logic:equal>
<logic:notEqual value="true" name="page" property="hasPrePage">
<td width="150" height="30"><div align="right">首页</div></td>
<td width="80" height="30"><div align="center">上一页</div></td>
</logic:notEqual>
<logic:equal value="true" name="page" property="hasNextPage">
<td width="80" height="30"><div align="center"><a
href="../product.do?method=showProductByTag&index=next&pageno=${page.currentPage
+1 }&msg=${msg }">下一页</a></div></td>
<td width="80" height="30"><div align="center"><a
href="../product.do?method=showProductByTag&index=end&pageno=${page.totalPage
}&msg=${msg }">尾页</a></div></td>
</logic:equal>
<logic:notEqual value="true" name="page" property="hasNextPage">
<td width="80" height="30"><div align="center">下一页</div></td>
<td width="80" height="30"><div align="center">尾页</div></td>
</logic:notEqual>
<td height="30" colspan="3"><div
align="center">页次${page.currentPage }/${page.totalPage
} 共${page.totalCount }条记录</div>
<div align="center"></div></td>
</tr>
可以显示相应的页面信息
然后productAction里面的showProductByTag代码如下：
Page page = new Page();
page.setEveryPage(10);
String pagemark = request.getParameter("goto");
if (pagemark == null) {
String state = request.getParameter("index");
String pageno = request.getParameter("pageno");
System.out.println("pageno=" + pageno);
if ("first".equals(state)) {
page.setCurrentPage(1);
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
} else if ("prew".equals(state)) {
page.setCurrentPage(Integer.parseInt(pageno));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
} else if ("next".equals(state)) {
page.setCurrentPage(Integer.parseInt(pageno));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
} else if ("end".equals(state)) {
page.setCurrentPage(Integer.parseInt(pageno));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
}
} else {
page.setCurrentPage(Integer.parseInt(pagemark));
Result result = pdp.productlist(page);
request.setAttribute("page", result.getPage());
request.setAttribute("productlist", result.getContent());
}
return mapping.findForward("showProduct");
-------------------------------------------------------------------
SSH的分页网上有不少的例子，有利用session的，有利用分页组件的。我几个师兄原来搞的SSH项目也有一个成熟的分页插件。
具体业务实现类中的分页方法：
Java代码
public List get*****(int pageNO){
DetachedCriteria dc = DetachedCriteria.forClass(****.class);
List list=*****Dao.getList(dc,pageNO,15);
int a = 0;
if (list.equals(null)){a=1;}
return list;
}
public PageBean getBean(int pageNO)
{
***** jg;
DetachedCriteria dc = DetachedCriteria.forClass(*****.class);
PageBean pb=collegeDao.getPageBean(dc,pageNO,15);
return pb;
}
然后是一个PageBean的工具类，负责创建分页属性和基本逻辑。
然后是页面的bean获取输出信息及分页属性。
我觉得单纯的拷贝，自己用的不是很顺手。于是自己也搞了一个，个人认为可以清晰的分层，实现这个分页。分层还是传统的SSH七层结构。
SSH结构思想参考我的另一篇随笔SSH思想之我见！
下面是分页思想，一个初始化方法和一个分页实现方法：
分页的util类：
package com.sy.util;
import java.util.List;
@SuppressWarnings("unchecked")
public class Page {
private int pageSize;
private int totalPage;
private int rowCount;
private int currentPage;
private int prePage;
private int nextPage;
private boolean hasNextPage;
private boolean hasPreviousPage;
private List list;
public Page() {
this.pageSize=10;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public int getTotalPage() {
return totalPage;
}
public void setTotalPage(int totalPage) {
this.totalPage = totalPage;
}
public int getRowCount() {
return rowCount;
}
public void setRowCount(int rowCount) {
this.rowCount = rowCount;
}
public int getCurrentPage() {
return currentPage;
}
public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}
public int getPrePage() {
return prePage;
}
public void setPrePage(int prePage) {
this.prePage = prePage;
}
public int getNextPage() {
return nextPage;
}
public void setNextPage(int nextPage) {
this.nextPage = nextPage;
}
public boolean isHasNextPage() {
return hasNextPage;
}
public void setHasNextPage(boolean hasNextPage) {
this.hasNextPage = hasNextPage;
}
public boolean isHasPreviousPage() {
return hasPreviousPage;
}
public void setHasPreviousPage(boolean hasPreviousPage) {
this.hasPreviousPage = hasPreviousPage;
}
public List getList() {
return list;
}
public void setList(List list) {
this.list = list;
}
}
分页的数据库操作和逻辑判断我把他单独用一个PageDaoImpl来实现：
/*
* 施杨的分页daoimpl类
* */
package com.sy.dao.impl;
import java.sql.SQLException;
import java.util.List;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.springframework.orm.hibernate3.HibernateCallback;
import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import com.sy.dao.BaseDao;
import com.sy.util.Page;
@SuppressWarnings("unchecked")
public class PageDaoImpl extends HibernateDaoSupport {
private String hql;
public Page page;
public int start;
public BaseDao dao;
public void setDao(BaseDao dao) {
this.dao = dao;
}
public void init(int start,String tableName){ // ͨ��init����ʵ����ij�ʼ��
page = new Page();
this.hql = "from "+tableName;
this.start = start;
setRowCount();
setTotalPage();
setCurrentPage();
setPrePage();
setNextPage();
setPreOrNextBoolean();
}
public int getRowCount(){
List list = dao.find(hql);
if(list.isEmpty()){
return 0;
}
return list.size();
}
public Page getPage(){
List list = (List)getHibernateTemplate().execute(new HibernateCallback(){
public Object doInHibernate(Session session) throws HibernateException, SQLException {
Query query = session.createQuery(hql);
query.setFirstResult(getStartIndex());
query.setMaxResults(page.getPageSize());
return query.list();
}
});
page.setList(list);
return page;
}
public void setPreOrNextBoolean() {
if (page.getCurrentPage() <= 1) {
page.setHasPreviousPage(false);
} else {
page.setHasPreviousPage(true);
}
if (page.getCurrentPage() >= page.getTotalPage()) {
page.setHasNextPage(false);
} else {
page.setHasNextPage(true);
}
}
public void setCurrentPage() {
if (start < 1) {
page.setCurrentPage(1);
}
if (start > page.getTotalPage()) {
page.setCurrentPage(page.getTotalPage());
}
page.setCurrentPage(start);
}
public void setPrePage() {
page.setPrePage(page.getCurrentPage() - 1);
}
public void setNextPage() {
page.setNextPage(page.getCurrentPage() + 1);
}
public void setTotalPage() {
int rowCount = getRowCount();
int pageSize = page.getPageSize();
if (rowCount > pageSize) {
if (rowCount % pageSize == 0) {
page.setTotalPage(rowCount / pageSize);
} else {
page.setTotalPage(1 + (rowCount / pageSize));
}
} else {
page.setTotalPage(1);
}
}
public void setRowCount() {
page.setRowCount(getRowCount());
}
public int getStartIndex() {
int startIndex = 0;
if (start < 0) {
startIndex = 0;
} else {
if (start > page.getTotalPage()) {
startIndex = page.getPageSize() * (page.getTotalPage() - 1);
} else {
startIndex = page.getPageSize() * (start - 1);
}
}
return startIndex;
}
}
然后是业务层接口，举例AdminService.java
//管理员service层接口
package com.sy.service;
import java.util.List;
import com.sy.util.Page;
import com.sy.vo.Admin;
public interface AdminService extends BaseService{
//分页初始化
public void init(int pno);
//分页实现
public Page getPage();
}
实现类AdminServiceImpl.java
//管理员service层实现类
package com.sy.service.impl;
import java.util.List;
import com.sy.dao.impl.AdminDaoImpl;
import com.sy.dao.impl.PageDaoImpl;
import com.sy.service.AdminService;
import com.sy.util.Page;
import com.sy.vo.Admin;
@SuppressWarnings("unchecked")
public class AdminServiceImpl extends BaseServiceImpl implements AdminService {
.
public Page getPage() {
return Pdao.getPage();
}
public void init(int pno) {
String tableName="Admin";
Pdao.init(pno,tableName);
}
}
struts的action层AdminAction.java
//管理员action实现类
package com.sy.action;
import java.util.List;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;
import org.apache.struts.action.ActionForm;
import org.apache.struts.action.ActionForward;
import org.apache.struts.action.ActionMapping;
import org.apache.struts.action.ActionMessage;
import org.apache.struts.action.ActionMessages;
import com.sy.form.AdminForm;
import com.sy.form.LoginForm;
import com.sy.service.AdminService;
import com.sy.util.MD5;
import com.sy.util.Page;
import com.sy.vo.Admin;
@SuppressWarnings("unchecked")
public class AdminAction extends BaseAction {
.
//查看管理员
public ActionForward listAdmins(ActionMapping mapping, ActionForm form,
HttpServletRequest request, HttpServletResponse response) {
AdminService as=(AdminService)super.getBean("AdminService");
int pno = (new Integer(request.getParameter("pno"))).intValue();
as.init(pno);
Page myPage = as.getPage();
List myList = as.getPage().getList();
request.setAttribute("myPage", myPage);
request.setAttribute("AdminList", myList);
return mapping.findForward("show");
}
}
结构清晰，也很实用。
页面lookAdmin.jsp
<%@ page language="java" pageEncoding="UTF-8"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%@ taglib uri="http://struts.apache.org/tags-bean" prefix="bean" %>
<%@ taglib uri="http://struts.apache.org/tags-html" prefix="html" %>
<%@ taglib uri="http://struts.apache.org/tags-logic" prefix="logic" %>
<%@ taglib uri="http://struts.apache.org/tags-tiles" prefix="tiles" %>
<html>
<head>
<meta http-equiv="Content-Language" content="zh-cn">
<meta http-equiv="Content-Type" content="text/html; charset=utf-8">
<title>施杨SSH新闻发布</title>
</head>
<body>
<center>
<h3>
查看管理员
</h3>
<br>
<a href="./admin/addAdmin.jsp">添加管理员</a>
<br>
<a href="./NewsPage2.do?pno=1">查看新闻</a>
<br>
<table border="2" width="600">
<tr>
<td>
用户名
</td>
<td>
密码
</td>
<td>
操作
</td>
</tr>
<c:forEach items="${requestScope['AdminList']}" var="admin">
<tr align="center">
<td width="20%" height="10"><c:out value="${admin.aname}" /></td>
<td width="20%" height="10"><c:out value="${admin.apassword}" /></td>
<td>
<a href="./editAdmin.do?aid=<c:out value="${admin.aid}"/>">修改</a>
<a href="./deleteAdmin.do?aid=<c:out
value="${admin.aid}"/>" onclick="javascript:return
confirm('您确定删除吗？')">删除</a>
</td>
</tr>
</c:forEach>
</table>
<table align="center" width="500">
<tr>
<td align="center" colspan="10">
<logic:present name="myPage">
<html:link page="/AdminPage.do?pno=1">首页</html:link>
<logic:equal name="myPage" property="hasPreviousPage" value="false">上一页</logic:equal>
<logic:equal name="myPage" property="hasPreviousPage" value="true">
<a href="./AdminPage.do?pno=<bean:write name="myPage" property="prePage"/>">上一页</a>
</logic:equal>
每页<bean:write name="myPage" property="pageSize"/>条记录
共<bean:write name="myPage" property="rowCount"/>条记录
当前第(<bean:write name="myPage"
property="currentPage"/>/<bean:write name="myPage"
property="totalPage"/>)页
<logic:equal name="myPage" property="hasNextPage" value="false">下一页</logic:equal>
<logic:equal name="myPage" property="hasNextPage" value="true">
<a href="./AdminPage.do?pno=<bean:write name="myPage" property="nextPage"/>">下一页</a>
</logic:equal>
<a href="./AdminPage.do?pno=<bean:write name='myPage' property='totalPage'/>">末页</a>
</logic:present>
</td>
</tr>
</table>
</center>
</body>
</html>