转载自：http://hi.baidu.com/wakin175/blog/item/4d26fef28faf9d14b17ec54e.html
1). 针对网上一些 struts2分页的例子 不完整 ，代码混乱繁琐 ，我特意写了一个分页的小例子，供大家参考，如果程序有什么纰漏， 请指出。
开发环境：
eclipse3.2 + myeclipse5.5
mysql5.0
tomcat5.5
Dreamweaver2004
2)建库，并导入脚本
这里给大家介绍一个mysql客户端工具 -- SQLyog ，非常好用。
----------------------------------------------------admin.sql------------------------------------------------
/*
SQLyog Community Edition- MySQL GUI v6.12
MySQL - 5.0.37-community-nt : Database - test
把这段脚本导入到mysql的test库里面（你可以先建一个test库 ，这样会省去很多麻烦）
*************************************************************************/
/*!40101 SET NAMES utf8 */;
/*!40101 SET SQL_MODE=''*/;
create database if not exists `test`;
USE `test`;
/*!40014 SET @OLD_FOREIGN_KEY_CHECKS=@@FOREIGN_KEY_CHECKS, FOREIGN_KEY_CHECKS=0 */;
/*!40101 SET @OLD_SQL_MODE=@@SQL_MODE, SQL_MODE='NO_AUTO_VALUE_ON_ZERO' */;
/*Table structure for table `admin` */
DROP TABLE IF EXISTS `admin`;
CREATE TABLE `admin` (
`id` int(11) NOT NULL auto_increment,
`user` char(20) default NULL,
`pass` char(20) default NULL,
PRIMARY KEY (`id`)
) ENGINE=InnoDB DEFAULT CHARSET=gb2312;
/*Data for the table `admin` */
insert into `admin`(`id`,`user`,`pass`) values (786432,'天使','#####'),(786433,'天使','#####'),(786434,'天使','#####'),(786435,'天使','#####'),(786436,'天使','#####'),(819200,'天使','#####'),(819201,'天使','#####'),(819202,'天使','#####'),(819203,'天使','#####'),(819204,'天使','#####'),(819205,'wangbacheng','#####'),(851968,'天使','#####'),(851969,'天使','#####'),(851970,'天使','#####'),(851971,'天使','#####'),(851972,'天使','#####');
/*!40101 SET SQL_MODE=@OLD_SQL_MO */;
/*!40014 SET FOREIGN_KEY_CHECKS=@OLD_FOREIGN_KEY_CHECKS */;
DE
3）建立数据库连接程序 ，也就是hibernate相关程序，都可以用eclipse自动生成，这个不用多说
在eclipse 中只要引入 hibernate核心包和struts2 包 就可以了
-------------------------------------------------HibernateSessionFactory.java---------------------------
package action;
import org.hibernate.HibernateException;
import org.hibernate.Session;
import org.hibernate.cfg.Configuration;
/**
* Configures and provides access to Hibernate sessions, tied to the
* current thread of execution. Follows the Thread Local Session
* pattern, see {@link http://hibernate.org/42.html }.
*/
public class HibernateSessionFactory {
/**
* Location of hibernate.cfg.xml file.
* Location should be on the classpath as Hibernate uses
* #resourceAsStream style lookup for its configuration file.
* The default classpath location of the hibernate config file is
* in the default package. Use #setConfigFile() to update
* the location of the configuration file for the current session.
*/
private static String CONFIG_FILE_LOCATION = "/hibernate.cfg.xml";
private static final ThreadLocal<Session> threadLocal = new ThreadLocal<Session>();
private static Configuration configuration = new Configuration();
private static org.hibernate.SessionFactory sessionFactory;
private static String configFile = CONFIG_FILE_LOCATION;
static {
try {
configuration.configure(configFile);
sessionFactory = configuration.buildSessionFactory();
} catch (Exception e) {
System.err
.println("%%%% Error Creating SessionFactory %%%%");
e.printStackTrace();
}
}
private HibernateSessionFactory() {
}
/**
* Returns the ThreadLocal Session instance. Lazy initialize
* the <code>SessionFactory</code> if needed.
*
* @return Session
* @throws HibernateException
*/
public static Session getSession() throws HibernateException {
Session session = (Session) threadLocal.get();
if (session == null || !session.isOpen()) {
if (sessionFactory == null) {
rebuildSessionFactory();
}
session = (sessionFactory != null) ? sessionFactory.openSession()
: null;
threadLocal.set(session);
}
return session;
}
/**
* Rebuild hibernate session factory
*
*/
public static void rebuildSessionFactory() {
try {
configuration.configure(configFile);
sessionFactory = configuration.buildSessionFactory();
} catch (Exception e) {
System.err
.println("%%%% Error Creating SessionFactory %%%%");
e.printStackTrace();
}
}
/**
* Close the single hibernate session instance.
*
* @throws HibernateException
*/
public static void closeSession() throws HibernateException {
Session session = (Session) threadLocal.get();
threadLocal.set(null);
if (session != null) {
session.close();
}
}
/**
* return session factory
*
*/
public static org.hibernate.SessionFactory getSessionFactory() {
return sessionFactory;
}
/**
* return session factory
*
* session factory will be rebuilded in the next call
*/
public static void setConfigFile(String configFile) {
HibernateSessionFactory.configFile = configFile;
sessionFactory = null;
}
/**
* return hibernate configuration
*
*/
public static Configuration getConfiguration() {
return configuration;
}
}
--------------------------------------------------Constants.java--------------------------------------------
package action;
public class Constants {
public static int PAGE_SIZE = 6;
}
--------------------------------------------------Admin.java-----------------------------------------------
package action;
/**
* Admin generated by MyEclipse Persistence Tools
*/
public class Admin implements java.io.Serializable {
// Fields
private Integer id;
private String user;
private String pass;
// Constructors
/** default constructor */
public Admin() {
}
/** minimal constructor */
public Admin(Integer id) {
this.id = id;
}
/** full constructor */
public Admin(Integer id, String user, String pass) {
this.id = id;
this.user = user;
this.pass = pass;
}
// Property accessors
public Integer getId() {
return this.id;
}
public void setId(Integer id) {
this.id = id;
}
public String getUser() {
return this.user;
}
public void setUser(String user) {
this.user = user;
}
public String getPass() {
return this.pass;
}
public void setPass(String pass) {
this.pass = pass;
}
}
-------------------------------------------------------------Admin.hbm.xml-------------------------------
<?xml version="1.0" encoding="utf-8"?>
<!DOCTYPE hibernate-mapping PUBLIC "-//Hibernate/Hibernate Mapping DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-mapping-3.0.dtd">
<!--
Mapping file autogenerated by MyEclipse Persistence Tools
-->
<hibernate-mapping>
<class name="action.Admin" table="admin" catalog="test">
<id name="id" type="java.lang.Integer">
<column name="id" />
<generator class="assigned" />
</id>
<property name="user" type="java.lang.String">
<column name="user" length="20" />
</property>
<property name="pass" type="java.lang.String">
<column name="pass" length="20" />
</property>
</class>
</hibernate-mapping>
-------------------------------------------------hibernate.cfg.xml------------------------------------------
<?xml version='1.0' encoding='UTF-8'?>
<!DOCTYPE hibernate-configuration PUBLIC
"-//Hibernate/Hibernate Configuration DTD 3.0//EN"
"http://hibernate.sourceforge.net/hibernate-configuration-3.0.dtd">
<!-- Generated by MyEclipse Hibernate Tools. -->
<hibernate-configuration>
<session-factory>
<property name="connection.username">root</property>
<property name="connection.url">
jdbc:mysql://localhost:3306/test
</property>
<property name="dialect">
org.hibernate.dialect.MySQLDialect
</property>
<property name="myeclipse.connection.profile">Mysql</property>
<property name="connection.password">root</property>
<property name="connection.driver_class">
com.mysql.jdbc.Driver
</property>
<mapping resource="action/Admin.hbm.xml" />
</session-factory>
</hibernate-configuration>
4).建个工具类，把一些方法封装到里面
--------------------------------------------------PagerHelper.java-----------------------------------------
package action;
import java.util.Collection;
import java.util.Iterator;
import org.hibernate.HibernateException;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;
/**
*
* @author like_dark
* 注意：java包命名的时候不能以 ”java“命名，例如 java.my.xxx ; 真是奇怪啊
*
*/
public class PagerHelper {
public Collection findWithPage(int pageSize, int startRow) throws
HibernateException {
Collection admins = null;
Transaction tx = null;
try {
Session session = HibernateSessionFactory.getSession();
tx = session.beginTransaction() ;
Query q = session.createQuery("from Admin");
q.setMaxResults(pageSize);
q.setFirstResult(startRow);
admins = q.list();
tx.commit();
} catch (HibernateException he) {
if (tx != null) {
tx.rollback();
}
throw he;
} finally {
HibernateSessionFactory.closeSession();
}
return admins;
}
public int getRows(String query) throws
HibernateException {
//query : select count(*) from Admin
int totalRows = 0;
Transaction tx = null;
try {
Session session = HibernateSessionFactory.getSession();
tx = session.beginTransaction();
totalRows = ((Integer) session.createQuery(query).list().iterator().next()).intValue() ;
tx.commit();
} catch (HibernateException he) {
if (tx != null) {
tx.rollback();
}
throw he;
} finally {
HibernateSessionFactory.closeSession();
}
return totalRows;
}
public static void main(String[] args) {
PagerHelper ph = new PagerHelper() ;
System.out.println("rows:"+ph.getRows("select count(*) from Admin")) ;
}
}
5) .struts2相关程序和配置
--------------------------------------------------struts.xml----------------------------------------
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE struts PUBLIC
"-//Apache Software Foundation//DTD Struts Configuration 2.0//EN"
"http://struts.apache.org/dtds/struts-2.0.dtd">
<struts>
<package name="default" namespace="/" extends="struts-default">
<action name="pager" class="action.PageAction">
<result name="success">
/index.jsp
</result>
<result name="fail">
/index.jsp
</result>
</action>
</package>
</struts>
----------------------------- PageAction.java ----------------------
package action;
import java.util.ArrayList;
import java.util.Collection;
import java.util.Map;
import com.opensymphony.xwork2.ActionContext;
import com.opensymphony.xwork2.ActionSupport;
public class PageAction extends ActionSupport {
private int totalRows; //总行数
private int pageSize = Constants.PAGE_SIZE; //每页显示的行数
private int currentPage; //当前页号
private int totalPages; //总页数
private boolean hasNext ; //是否有下一页
private boolean hasPrevious ; //是否有上一页
private Collection CurrentList; //当前数据集
private Collection indexList ; //页码集合
public Collection getCurrentList() {
return CurrentList;
}
public void setCurrentList(Collection currentList) {
CurrentList = currentList;
}
/**
* 这里最好用一个引用参数化
*/
public Collection getIndexList() {
ArrayList result = new ArrayList();
for(int i = 1;i<=getTotalPages();i++){
result.add(new Integer(i));
}
return result ;
}
public void setIndexList(Collection indexList) {
this.indexList = indexList;
}
public String execute() throws Exception {
int totalRows = 0 ;
try{
PagerHelper ph = new PagerHelper() ;
totalRows = ph.getRows("select count(*) from Admin") ; //总行数
totalPages = (totalRows + pageSize - 1) /pageSize; //总页数
setIndexList(getIndexList()) ; //生成页码集合
if (currentPage==0 || currentPage<1) {
first();
}
if(currentPage > totalPages){
last();
}
if(currentPage >= 1 && currentPage < totalPages){
hasNext = true ;
}
if(currentPage > 1 && currentPage <= totalPages){
hasPrevious = true ;
}
/**
* 为了利用session 可以实现SessionAware接口 然后重载 void setSession(Map session) 方法
* action implementation SessionAware{
* private Map session ;
* void setSession(Map session){
* this.session = session ;
* }
* session.put(...); session.get(..)
* 或者 继承import com.opensymphony.xwork2.ActionContext;
* ActionContext ctx = ActionContext.getContext();
Map session = ctx.getSession() ;
*/
CurrentList = ph.findWithPage(Constants.PAGE_SIZE, getStartRow()) ;
return SUCCESS ;
}catch(Exception e){
e.printStackTrace() ;
return ERROR ;
}
}
public int getCurrentPage() {
return currentPage;
}
public void setCurrentPage(int currentPage) {
this.currentPage = currentPage;
}
public int getPageSize() {
return pageSize;
}
public void setPageSize(int pageSize) {
this.pageSize = pageSize;
}
public int getStartRow() {
if(getCurrentPage() == 1)
return 0;
else
return (getCurrentPage()-1) * pageSize;
}
public int getTotalPages() {
return totalPages;
}
public void setTotalPages(int totalPages) {
this.totalPages = totalPages;
}
public int getTotalRows() {
return totalRows;
}
public void setTotalRows(int totalRows) {
this.totalRows = totalRows;
}
public void first() { //首页
currentPage = 1;
}
/*public void previous() { //上一页
if (currentPage == 1) {
return;
}
currentPage--;
}
public void next() { //下一页
if (currentPage < totalPages) {
currentPage++;
}
}*/
public void last() { //尾页
currentPage = totalPages;
}
public boolean isHasNext() {
return hasNext;
}
public void setHasNext(boolean hasNext) {
this.hasNext = hasNext;
}
public boolean isHasPrevious() {
return hasPrevious;
}
public void setHasPrevious(boolean hasPrevious) {
this.hasPrevious = hasPrevious;
}
}
----------------------------struts.properties------------------------------
#struts.custom.i18n.resources=globalMessages
struts.action.extension=do
5) web相关配置和程序
--------------------- web.xml -----------------------------------
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_9" version="2.4" xmlns="http://java.sun.com/xml/ns/j2ee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/j2ee http://java.sun.com/xml/ns/j2ee/web-app_2_4.xsd">
<display-name>Struts Blank</display-name>
<filter>
<filter-name>struts2</filter-name>
<filter-class>org.apache.struts2.dispatcher.FilterDispatcher</filter-class>
</filter>
<filter-mapping>
<filter-name>struts2</filter-name>
<url-pattern>/*</url-pattern>
</filter-mapping>
<welcome-file-list>
<welcome-file>index.jsp</welcome-file>
</welcome-file-list>
</web-app>
------------------- index.jsp --------------------------------------
<%@ page language="java" contentType="text/html; charset=gb2312"
pageEncoding="gb2312"%>
<%@ taglib prefix="s" uri="/struts-tags" %>
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=gb2312">
<title>Insert title here</title>
<style type="text/css">
<!--
A:link {
COLOR: #000099; TEXT-DECORATION: none
}
A:visited {
COLOR: #001646; TEXT-DECORATION: none
}
.location {
COLOR: #000000
}
A:active {
COLOR: #ff0000; TEXT-DECORATION: none
}
A:hover {
COLOR: #ff0000; FONT-STYLE: normal; TEXT-DECORATION: underline
}
-->
</style>
</head>
<body>
<s:form action="pager.action">
<h1>Welcome My Pager</h1><BR>
<hr>
<!--在这里显示数据-->
<p>UserID Name Pass</p>
<s:iterator value="CurrentList" status="admin">
<s:property value="id"/>
<s:property value="user"/>
<s:property value="pass"/>
<BR>
</s:iterator>
<!--定义几个动作-->
<s:url id="url_pre" value="pager.action">
<s:param name="currentPage" value="currentPage-1"></s:param>
</s:url>
<s:url id="url_next" value="pager.action">
<s:param name="currentPage" value="currentPage+1"></s:param>
</s:url>
<s:url id="url_first" value="pager.action">
<s:param name="currentPage" value="1"></s:param>
</s:url>
<s:url id="url_last" value="pager.action">
<s:param name="currentPage" value="totalPages"></s:param>
</s:url>
<!--显示页码 -->
<hr>
第 <s:property value="currentPage"/>/<s:property value="totalPages"/> 页
<s:a href ="%{url_first}"><font face=webdings >9</font></s:a>
<s:if test="hasPrevious">
<s:a href="%{url_pre}"><font face=webdings >7</font></s:a>
</s:if>
<!--显示数字页码1，2，3，4。。。。 -->
<!--设置两个参数 然后比较是否相等 如果相等 把当前链接加亮 -->
<s:set name="currpage" value="<s:property value='currentPage'/>" />
<s:iterator value="indexList" status="number">
<!-- <s:set name="listpage" value="<s:property/>" />
<s:if test="#currpage == #listpage">
Max's file here
</s:if>
-->
<!-- <s:url id="url" value="pager.action">
pass the currentPage parameter 这段代码不能用
<s:param name="currentPage" value=""></s:param>
</s:url>
<s:a href="%{url}">[<s:property/>]</s:a>
-->
<a id="pager_" href="pager.action?currentPage=<s:property/>">[<s:property/>]</a>
</s:iterator>
<s:if test="hasNext">
<s:a href="%{url_next}"><font face=webdings >8</font></s:a>
</s:if>
<s:a href ="%{url_last}"><font face=webdings >:</font></s:a>
</s:form>
</body>
</html>
6）。测试
http://localhost:8080/PageDemo/pager.action
遗留的问题 ：我想把我当前的 那个链接页码码加亮 我是这样写的，可是实现不了，如果谁能解决，给我留言，谢谢
<s:set name="currpage" value="<s:property value='currentPage'/>" />
<s:iterator value="indexList" status="number">
<s:set name="listpage" value="<s:property/>" />
<s:if test="#currpage == #listpage">
如果当前页是2 那么把2加亮,我就知道是第二页了
</s:if>
。。。。。。。。。
扩展 ：这个程序当页码太多时，比如100 页 美观就是个问题了，掏宝上面那样，只显示几个分页码 ，把中间的部分省略掉，有兴趣的朋友可以试一下。