通用分页：pager taglib执行分页（本例采用struts2+hibernate）

使用此分页插件很简单就可以实现多种分页风格！其官方网址为：pager taglib 网址在此下载要用的jar包及实例。现在开始分页：

1.首先导入所需jar包：

2.创建两个工具类：PageMode.java(此类用来生成便利需要的集合，及其总的数据行数) MakePageModel.java

package com.util.pageUtil;

import java.util.List;
/**
* @author ZhangJunpeng
*  @declare:此类用来生成便利需要的集合，及其总的数据行数
**/
public class PageMode {
    private int total;
    private List datas;

    public List getDatas() {
        return datas;
    }

    public void setDatas(List datas) {
        this.datas = datas;
    }

    public int getTotal() {
        return total;
    }

    public void setTotal(int total) {
        this.total = total;
    }
}

------------------------------------------------

package com.util.pageUtil;
import java.util.ArrayList;
import java.util.List;
import org.hibernate.Query;
import org.hibernate.Session;
import org.hibernate.Transaction;

import com.school.dao.BaseHibernateDAO;
//import org.springframework.orm.hibernate3.support.HibernateDaoSupport;
import com.sun.org.apache.bcel.internal.generic.NEW;

/**
*@method:MakePageModel
*@author ZhangJunpeng
**/
public class MakePageModel{
    /**
    *@param offset 当前页数
    *@param pagesize 每页显示的行数
    *@param objName 传入要传入对象的名字
    *@return pageModel pm
    **/
    private BaseHibernateDAO baseHibernateDAO=new BaseHibernateDAO();
    public BaseHibernateDAO getBaseHibernateDAO() {
        return baseHibernateDAO;
    }
    public void setBaseHibernateDAO(BaseHibernateDAO baseHibernateDAO) {
        this.baseHibernateDAO = baseHibernateDAO;
    }
    @SuppressWarnings("unchecked")
    public PageMode makePageModel(int offset, int pagesize,String objName) {
        String queryCountHql = "select count(*) from "+objName;
        List datas=new ArrayList();
        int totoalPages=0;
        Session session=baseHibernateDAO.getSession();
        Transaction transaction=null;
        try{
        transaction=session.beginTransaction();
        Query query = session.createQuery(queryCountHql);
        totoalPages = ((Integer)query.uniqueResult()).intValue();
        System.out.println(">>>1");
        datas = session .createQuery("from "+objName)
                    .setFirstResult(offset)
                    .setMaxResults(pagesize)
                    .list();
        System.out.println(">>>2");
        transaction.commit();
        System.out.println(">>>3"+totoalPages);
        }catch (Exception e) {
            e.printStackTrace();
            transaction.rollback();// TODO: handle exception
        }finally{
//            session.close();
        }
        PageMode pm = new PageMode();
        pm.setTotal(totoalPages);
        pm.setDatas(datas);
        return pm;
    }
}

3.创建相应的DAO类，实现pageMode的查询（就是返回指定首尾的结果集，及其总的数据数）例如：

/**
     * 用于分页显示的查询
     * */
    public PageMode findAll(int offset, int pagesize){
        String queryCountHql = "select count(*) from Admin";
        Query query = getSession().createQuery(queryCountHql);
        int total = ((Number)query.uniqueResult()).intValue();
        List datas = getSession().createQuery("from Admin")
                    .setFirstResult(offset)
                    .setMaxResults(pagesize)
                    .list();
        PageMode pm = new PageMode();
        pm.setTotal(total);
        pm.setDatas(datas);
        return pm;
    }

如果是struts，或是struts2的话，在action内需要处理如下数据：(STRUTS2示例)

        int offset = 0;
        AdminDAO adminDAO = new AdminDAO();//需要查询类的DAO
        HttpServletRequest request = ServletActionContext.getRequest();
        try {
            if (request.getParameter("pager.offset") == null) {//pager.offset，taglib标签自带的属性
                  offset = 0;
                 } else {
                  offset = Integer.parseInt(request
                    .getParameter("pager.offset"));
                 }
            int maxPageItems;//每页显示行数
            if(request.getAttribute("maxPageItems")==null){
                maxPageItems=10;
            }else{
                maxPageItems = Integer.parseInt(request.getParameter("maxPageItems"));
            }
            logger.debug(">>>>"+maxPageItems);
            PageMode pm = adminDAO.findAll(offset, maxPageItems);//查询PageMode
            request.setAttribute("admins", pm); //设置范围

            if (logger.isDebugEnabled()) {
                logger.debug("viewAdmin() - end");
            }
            return "viewAdmin";//转入视图层
        } catch (Exception e) {
            logger.error("viewAdmin()", e);

            logger.error(e.getMessage());
            return ERROR;
        }

4.根据返回的pageMode可以保存在指定的范围内，然后逃到页面进行显示数据：

在需要显示分页的地方放入：


       view plaincopy to clipboardprint?
<!--别忘记引入插件--> 
<%@ taglib uri="http://jsptags.com/tags/navigation/pager" prefix="pg" %> 
<div> 
        <pg:pager url="forward!viewAdmin.action" maxPageItems="10" items="${admins.total}" export="currentPageNumber=pageNumber"> 
        <pg:first> 
            <a href="${pageUrl}" mce_href="${pageUrl}">首页</a> 
        </pg:first> 
        <pg:prev> 
            <a href="${pageUrl }" mce_href="${pageUrl }">上一页</a> 
        </pg:prev> 
        <pg:pages> 
            <c:choose> 
                <c:when test="${currentPageNumber eq pageNumber}"> 
                    <font color="red">${pageNumber }</font> 
                </c:when> 
                <c:otherwise> 
                    <a href="${pageUrl }" mce_href="${pageUrl }">${pageNumber }</a> 
                </c:otherwise> 
            </c:choose> 
        </pg:pages> 
        <pg:next> 
            <a href="${pageUrl }" mce_href="${pageUrl }">下一页</a> 
        </pg:next> 
        <pg:last> 
            <a href="${pageUrl }" mce_href="${pageUrl }">尾页</a> 
        </pg:last> 
    </pg:pager> 
    </div>
<!--别忘记引入插件-->
<%@ taglib uri="http://jsptags.com/tags/navigation/pager" prefix="pg" %>
<div>
     <pg:pager url="forward!viewAdmin.action" maxPageItems="10" items="${admins.total}" export="currentPageNumber=pageNumber">
  <pg:first>
   <a href="${pageUrl}" mce_href="${pageUrl}">首页</a>
  </pg:first>
  <pg:prev>
   <a href="${pageUrl }" mce_href="${pageUrl }">上一页</a>
  </pg:prev>
  <pg:pages>
   <c:choose>
    <c:when test="${currentPageNumber eq pageNumber}">
     <font color="red">${pageNumber }</font>
    </c:when>
    <c:otherwise>
     <a href="${pageUrl }" mce_href="${pageUrl }">${pageNumber }</a>
    </c:otherwise>
   </c:choose>
  </pg:pages>
  <pg:next>
   <a href="${pageUrl }" mce_href="${pageUrl }">下一页</a>
  </pg:next>
  <pg:last>
   <a href="${pageUrl }" mce_href="${pageUrl }">尾页</a>
  </pg:last>
</pg:pager>
    </div>       
  
  
参数：url：所要跳转的action   maxPageItems：每页显示行数   items： 前面在action中保存的PageMode中的 总数据数

注意：在页面便利数据时候，也是利用PageMode中的list进行遍历的


本文来自CSDN博客，转载请标明出处：http://blog.csdn.net/icejadelove/archive/2009/10/13/4663223.aspx