ajaxservlet.java

一个Ajax演示程序的项目文件

package com.test.servlet;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
import java.util.List;
import java.util.Random;

import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.test.bean.TestBean;
import com.test.util.Pagination;

/**
 * 
 * @author freeman983 响应ajax请求返回xml数据
 */
public class AjaxServlet extends HttpServlet {

	/**
	 * The doGet method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doPost(request, response);
		// AjaxXmlBuilder builder = new AjaxXmlBuilder();
		// builder.setEncoding("gb2312");
		// List list=this.getTestList(0);
		//		
		// try {
		// int count=10;
		// Pagination page=new Pagination(request,count);
		// for(int i=0;i<list.size();i++){
		// TestBean bean=(TestBean)list.get(i);
		//				 
		// builder.addItemAsCData("id",bean.getId().toString());
		// builder.addItemAsCData("name",bean.getName());
		// builder.addItemAsCData("sex",bean.getSex());
		// builder.addItemAsCData("age",bean.getAge().toString());
		// }
		//			
		// } catch (Exception e) {
		// e.printStackTrace();
		// }
		//		
		// writeResponse(request, response, builder.toString());
	}

	/**
	 *  生成测试数据
	 * @param start
	 * @param size
	 * @return
	 */
	public List getTestList(int start, int size) {

		List list = new ArrayList();
		Random random = new Random();

		for (int i = 0; i < 100; i++) {
			TestBean bean = new TestBean();
			bean.setId(new Integer(i));
			bean.setName("小强" + i);
			bean.setSex(i % 2==0?"女":"男");
			bean.setAge(new Integer( random.nextInt(10000)));
			list.add(bean);
		}
		List result = new ArrayList();
				for (int i = 0; i < list.size(); i++) {
			if (i >= start && i <start + size)
				result.add(list.get(i));
		}
		return result;
	}

	/**
	 * The doPost method of the servlet. <br>
	 * 
	 * This method is called when a form has its tag value method equals to
	 * post.
	 * 
	 * @param request
	 *            the request send by the client to the server
	 * @param response
	 *            the response send by the server to the client
	 * @throws ServletException
	 *             if an error occurred
	 * @throws IOException
	 *             if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		
		StringBuffer resultXML = new StringBuffer();
		int pageNo = new Integer(request.getParameter("pageNo")).intValue();
		
		try {
			resultXML.append("<?xml version='1.0' encoding='gb2312'?>");
			resultXML.append("<ajax-response>\n");
			resultXML.append("<root>\n");

			Pagination page = new Pagination(request, 100);
			List list = this.getTestList(page.getStart(), page.getPageSize());
			for (int i = 0; i < list.size(); i++) {
				TestBean bean = (TestBean) list.get(i);
				resultXML.append("<data>\n");
				resultXML
						.append("\t<id>" + bean.getId().toString() + "</id>\n");
				resultXML.append("\t<name>" + bean.getName() + "</name>\n");
				resultXML.append("\t<sex>" + bean.getSex() + "</sex>\n");
				resultXML.append("\t<age>" + bean.getAge().toString()
						+ "</age>\n");
				resultXML.append("</data>\n");
			}

			resultXML.append("<pagination>\n");
			resultXML.append("\t<total>" + page.getTotal() + "</total>\n");
			resultXML.append("\t<start>" + page.getStart() + "</start>\n");
			resultXML.append("\t<end>" + page.getEnd() + "</end>\n");
			resultXML.append("\t<pageno>" + page.getPageNo() + "</pageno>\n");
			resultXML.append("</pagination>\n");

			resultXML.append("</root>\n");
			resultXML.append("</ajax-response>");
		} catch (Exception e) {
			e.printStackTrace();
		}
		writeResponse(request, response, resultXML.toString());
	}

	public void writeResponse(HttpServletRequest request,
			HttpServletResponse response, String result) throws IOException {

		response.setContentType("text/xml");
		response.setHeader("Cache-Control", "no-cache");
		response.setHeader("Content-Type", "text/xml; charset=gb2312");
		PrintWriter pw = response.getWriter();
		pw.write(result);
		pw.close();
	}

}