dom4j建立XML文件
阿新 • • 發佈：2019-01-08
下面用一個公告例項顯示dom4j的使用:將公告資訊儲存到xml檔案中。
index.jsp：用於收集公告資訊
PlacardServlet.java：<%@ page language="java" import="java.util.*" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <%@taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core"%> <%@ taglib uri="/struts-tags" prefix="s"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd"> <html> <head> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8"> <title>起始頁</title> </head> <body> <form name="form1" method="post" action="PlacardServlet" target="_blank" onsubmit="return check(this)"> 公告標題：<input name="title" type="text" id="title" size="52"> 公告內容：<textarea name="content" cols="50" rows="9" id=content></textarea> <input name="Submit" type="submit" class="btn_grey" value="儲存"> <input name="Submit2" type="reset" class="btn_grey" value="重置"> </form> </body> </html>
package com.home.web.servlet; import java.io.File; import java.io.FileWriter; import java.io.IOException; import java.text.DateFormat; import java.text.SimpleDateFormat; import java.util.Date; import javax.servlet.ServletException; import javax.servlet.annotation.WebServlet; import javax.servlet.http.HttpServlet; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import org.dom4j.Document; import org.dom4j.DocumentHelper; import org.dom4j.Element; import org.dom4j.io.OutputFormat; import org.dom4j.io.SAXReader; import org.dom4j.io.XMLWriter; /** * Servlet implementation class PlacardServlet */ @WebServlet("/PlacardServlet") public class PlacardServlet extends HttpServlet { private static final long serialVersionUID = 1L; /** * @see HttpServlet#HttpServlet() */ public PlacardServlet() { super(); // TODO Auto-generated constructor stub } /** * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response) */ protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { // TODO Auto-generated method stub response.getWriter().append("Served at: ").append(request.getContextPath()); } /** * @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response) */ protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException { response.setContentType("text/html"); String fileUrl = request.getRealPath("/xml/placard.xml"); File file = new File(fileUrl); String title = request.getParameter("title"); String content = request.getParameter("content"); Document document = null; Element placard = null; DateFormat df = new SimpleDateFormat("yyyy 年 MM 月 dd 日 HH 時 mm 分"); if (!file.exists()) { document = DocumentHelper.createDocument(); placard = DocumentHelper.createElement("placard"); document.setRootElement(placard); placard.addAttribute("version", "2.0"); Element description = placard.addElement("description"); description.setText("公告欄"); Element createTime = placard.addElement("createTime"); createTime.setText("創建於" + df.format(new Date())); } else { SAXReader reader = new SAXReader(); try { document = reader.read(new File(fileUrl)); placard = document.getRootElement(); } catch (Exception e) { e.printStackTrace(); } } /********* 新增公告資訊 **********/ String id = String.valueOf(placard.elements("info").size() + 1); Element info = placard.addElement("info"); info.addAttribute("id", id); Element title_info = info.addElement("title"); title_info.setText(title); Element content_item = info.addElement("content"); content_item.addCDATA(content); Element pubDate_item = info.addElement("pubDate"); df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss"); pubDate_item.setText(df.format(new Date())); OutputFormat format = OutputFormat.createPrettyPrint(); format.setEncoding("UTF-8"); try { XMLWriter writer=new XMLWriter(new FileWriter(fileUrl), format); writer.write(document); writer.close(); } catch (Exception e) { e.printStackTrace(); } request.getRequestDispatcher("xml/placard.xml").forward(request, response); } }
注意要現在該例項根目錄下建立xml資料夾，不需要建立XML檔案
效果：
