基于AJAX的数据分页源代码

package com.eamoi.ajax; import java.io.IOException; import java.util.*; import org.jdom.*; import org.jdom.output.Format; import org.jdom.output.XMLOutputter; import javax.servlet.RequestDispatcher; import javax.servlet.ServletException; import javax.servlet.ServletRequest; import javax.servlet.ServletResponse; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; public class NewsManager extends HttpServlet { private static final long serialVersionUID = 1L; private static final int COUNTAPAGE = 6; /** * 服务的总入口 */ public void service (HttpServletRequest request, HttpServletResponse response)throws IOException, ServletException { this.getNews(request,response); } /** * 将所获取的新闻列表输出为客户端可视的XML文档 * @param request * @param response * @throws IOException * @throws ServletException */ private void getNews(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { int currentPage = 0; if(request.getParameter("currentPage")!=null) currentPage = Integer.parseInt(request.getParameter("currentPage")); // System.out.println("当前页："+String.valueOf(currentPage)); //获取新闻列表 NewsService service = new NewsService(); Collection results = new ArrayList(); int totalPage = 0; try { News[] newslist = service.getAllMessage(); if((newslist!=null)&&(newslist.length!=0)) { totalPage = (newslist.length%COUNTAPAGE==0)?(newslist.length/COUNTAPAGE):(newslist.length/COUNTAPAGE+1); if(currentPage<=0) currentPage=1; if(currentPage>totalPage) currentPage = totalPage; for(int i=((currentPage-1)*COUNTAPAGE);i<COUNTAPAGE*currentPage;i++) { if(i>=newslist.length) break; results.add(newslist[i]); } } //输出为范式良好的XML文档 response.setContentType("application/xml"); Document doc = new Document(); Element root = new Element("list"); Element e_page = new Element("currentPage").addContent(String.valueOf(currentPage)); root.addContent(e_page); Element e_total = new Element("totalPage").addContent(String.valueOf(totalPage));; root.addContent(e_total); Element e_newslist = new Element("newslist"); Iterator iterator = results.iterator(); for(int i=0;i<results.size();i++) { News news = (News)iterator.next(); Element e_news = new Element("news").setAttribute("id",news.getId()); e_news.addContent(new Element("title").addContent(news.getTitle())); e_news.addContent(new Element("submittime").addContent(news.getSubmittime())); e_newslist.addContent(e_news); } root.addContent(e_newslist); doc.addContent(root); XMLOutputter outputter = new XMLOutputter(Format.getPrettyFormat().setEncoding("ISO8859-1")); outputter.output(doc,response.getWriter()); }catch(Exception ex) { this.handleError(ex); } } /** * 错误处理 * @param ex */ private void handleError(Exception ex) { ex.printStackTrace(); System.out.println(ex.toString()); } /** * 处理页面转向 * @param strForward * @param request * @param response * @throws IOException * @throws ServletException */ private void forward(String strForward, HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException { RequestDispatcher dispatcher = request.getRequestDispatcher(strForward); dispatcher.forward((ServletRequest)request, (ServletResponse)response); } }