struts2 hibernate分页.doc

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 + myeclipse5.5mysql5.0tomcat5.5Dreamweaver20042)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 v6.12MySQL - 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 SETSQL_MODE=OLD_SQL_MO*/;/*!40014 SETFOREIGN_KEY_CHECKS=OLD_FOREIGN_KEY_CHECKS*/;DE3）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, seelink/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 threadLocal = new ThreadLocal(); 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 SessionFactory 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;-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.xml- -hibernate.cfg.xml-root jdbc:mysql:/localhost:3306/test org.hibernate.dialect.MySQLDialectMysqlroot com.mysql.jdbc.Driver4).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) throwsHibernateException 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(); mit(); catch (HibernateException he) if (tx != null) tx.rollback(); throw he; finally HibernateSessionFactory.closeSession(); return admins;public int getRows(String query) throwsHibernateException /query : select count(*) from Admin int totalRows = 0; Transaction tx = null; try Session session = HibernateSessionFactory.getSession(); tx = session.beginTransaction(); totalRows = (Long) session.createQuery(query).list().iterator().next().intValue() ; mit(); 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- /index.jsp /index.jsp - 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 totalPages) last(); if(currentPage = 1 & 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 setT