本文實例講述了JSP基于dom解析xml的方法。分享給大家供大家參考，具體如下：
初次學習用dom操作xml文件，有很多不足之處，牛人多給點建議，練習時我沒對中文做亂碼處理，也沒做驗證哦！O(∩_∩)O~
實體類：User
public class User { private String name; private String pwd; private String email; public String getName() { return name; } public void setName(String name) { this.name = name; } public String getPwd() { return pwd; } public void setPwd(String pwd) { this.pwd = pwd; } public String getEmail() { return email; } public void setEmail(String email) { this.email = email; }}數據訪問層接口：UserDao
public interface UserDao { boolean login(String name, String pwd); void insertUser(User user); List<User> selectUser(); void updateUser(User user); boolean deleteUser(String name); public User findByName(String name);}接口實現類：UserDaoImpl
public class UserDaoImpl implements UserDao { private static final String PATH="xml文件路徑"; private void build(Document dom) { try { //定義轉換器 Transformer f = TransformerFactory.newInstance().newTransformer(); //設置輸出的編碼格式 f.setOutputProperty(OutputKeys.ENCODING, "UTF-8"); //構建dom源 DOMSource source = new DOMSource(dom); //指定文件存放的目標路勁 StreamResult sr = new StreamResult(new File(PATH)); //執行轉換操作 f.transform(source, sr); } catch (Exception e) { e.printStackTrace(); } } //登陸 public boolean login(String name, String pwd) { boolean flag = false; try { //根據以有的xml文件創建Document對象 Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new File(PATH)); //獲取user節點下的子節點 NodeList list = dom.getElementsByTagName("user"); //遍歷list，數據匹配退出 for(int i = 0; i<list.getLength(); i++) { Element el = (Element)list.item(i); if(name.equals(el.getAttribute("name")) && pwd.equals(el.getAttribute("pwd"))) { flag = true; break; } } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return flag; } //添加操作 public void insertUser(User user) { try { //創建全新的Document對象 Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().newDocument(); //創建根節點users Element el = dom.createElement("users"); //將根節點添加到dom中 dom.appendChild(el); //創建子節點 Element e2 = dom.createElement("user"); //將子節點添加到根節點中 el.appendChild(e2); //取得xml文件中現有的信息 List<User> users = this.selectUser(); for(int i = 0; i < users.size(); i++){ //創建節點user Element el3 = dom.createElement("user"); User us =users.get(i); //設置節點的屬性（name,pwd,email） el3.setAttribute("name", us.getName()); el3.setAttribute("pwd", us.getPwd()); el3.setAttribute("email", us.getEmail()); //添加到根節點中 el.appendChild(el3); } e2.setAttribute("name", user.getName()); e2.setAttribute("pwd", user.getPwd()); e2.setAttribute("email", user.getEmail()); build(dom); } catch (ParserConfigurationException e) { // TODO Auto-generated catch block e.printStackTrace(); } } //查詢操作 public List<User> selectUser() { List<User> userList = new ArrayList<User>(); try { //根據已有的xml文件創建dom Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new File(PATH)); //獲取所有user節點下的子節點 NodeList list = dom.getElementsByTagName("user"); for(int i = 0;i <list.getLength();i++){ User user =new User(); Element element = (Element)list.item(i); user.setName(element.getAttribute("name")); user.setPwd(element.getAttribute("pwd")); user.setEmail(element.getAttribute("email")); userList.add(user); } } catch (Exception e) { // TODO Auto-generated catch block e.printStackTrace(); } return userList; } //修改操作 public void updateUser(User user) { try { //根據以有的xml文件創建dom Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new File(PATH)); //獲取user節點下的子節點 NodeList list = dom.getElementsByTagName("user"); //遍歷list for(int i = 0;i < list.getLength();i++) { Element el = (Element)list.item(i); //根據name屬性去修改 if(user.getName().equals(el.getAttribute("name"))) { el.setAttribute("pwd", user.getPwd()); el.setAttribute("email", user.getEmail()); build(dom); } } } catch (SAXException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } catch (ParserConfigurationException e) { // TODO Auto-generated catch block e.printStackTrace(); } } //刪除操作 public boolean deleteUser(String name) { try { //根據以有xml文件創建domcumet對象 Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new File(PATH)); //獲取user節點下的子節點 NodeList list = dom.getElementsByTagName("user"); //遍歷list for(int i=0;i<list.getLength();i++) { Element el = (Element)list.item(i); if(name.equals(el.getAttribute("name"))) { el.getParentNode().removeChild(el); build(dom); return true; } } } catch (Exception e) { // TODO: handle exception } return false; } //根據name查找 public User findByName(String name) { User user = new User(); try { //根據以后的xml文件創建document對象 Document dom = DocumentBuilderFactory.newInstance().newDocumentBuilder().parse(new File(PATH)); //獲取user節點下的子節點集合 NodeList list = dom.getElementsByTagName("user"); for(int i=0;i<list.getLength();i++) { Element el = (Element)list.item(i); if(name.equals(el.getAttribute("name"))) { user.setName(el.getAttribute("name")); user.setPwd(el.getAttribute("pwd")); user.setEmail(el.getAttribute("email")); break; } } } catch (Exception e) { e.printStackTrace(); } return user; }}業務邏輯層接口：UserService
boolean login(String name, String pwd);void insertUser(User user);List<User> selectUser();void updateUser(User user);boolean deleteUser(String name);public User findByName(String name);
接口實現類：UserServiceImpl
public class UserServiceImpl implements UserService { UserDao dao = new UserDaoImpl(); public boolean login(String name, String pwd) { return dao.login(name, pwd); } public void insertUser(User user) { dao.insertUser(user); } public List<User> selectUser() { return dao.selectUser(); } public void updateUser(User user) { dao.updateUser(user); } public boolean deleteUser(String name) { return dao.deleteUser(name); } public User findByName(String name) { return dao.findByName(name); }}控制層：UserAction
public class UserAction extends ActionSupport{ private User user; public User getUser() { return user; } public void setUser(User user) { this.user = user; } UserService userService = new UserServiceImpl(); public String selectUser(){ HttpServletRequest request = ServletActionContext.getRequest(); List<User> users = new ArrayList<User>(); users = userService.selectUser(); request.setAttribute("USER", users); return "select"; } /** * 登陸 * @return */ public String login(){ if(user.getName() != null && user.getPwd() != null) { boolean flag = userService.login(user.getName(), user.getPwd()); if(flag) { return SUCCESS; } } return ERROR; } /** * 修改 * @return */ public String update(){ userService.updateUser(user); return "update"; } /** * 編輯 * @return */ public String edit(){ HttpServletRequest request = ServletActionContext.getRequest(); String name = request.getParameter("uName"); if(name != null) { User u = userService.findByName(name); request.setAttribute("USER", u); } return "edit"; } /** * 刪除 * @return */ public String delete(){ HttpServletRequest request = ServletActionContext.getRequest(); String name = request.getParameter("uName"); boolean flag = userService.deleteUser(name); System.out.println(flag); return SUCCESS; } /** * 添加 * @return */ public String insert(){ userService.insertUser(user); return "insert"; }}struts.xml配置（本人用的的struts2）：
<?xml version="1.0" encoding="UTF-8" ?><!DOCTYPE struts PUBLIC "-//Apache Software Foundation//DTD Struts Configuration 2.1.7//EN" "http://struts.apache.org/dtds/struts-2.1.7.dtd"><struts> <package name="file" extends="struts-default"> <action name="list" class="com.jun.action.UserAction" method="selectUser"> <result name="select">/list.jsp</result> </action> <action name="login" class="com.jun.action.UserAction" method="login"> <result name="success" type="redirectAction">/list.action</result> <result name="error">/login.jsp</result> </action> <action name="insert" class="com.jun.action.UserAction" method="insert"> <result name="insert" type="redirectAction">/list.action</result> </action> <action name="delete" class="com.jun.action.UserAction" method="delete"> <result type="redirect">/list.action</result> </action> <action name="update" class="com.jun.action.UserAction" method="update"> <result name="update" type="redirectAction">/list.action</result> </action> <action name="edit" class="com.jun.action.UserAction" method="edit"> <result name="edit">/update.jsp</result> </action> </package></struts>
web.xml配置
<?xml version="1.0" encoding="UTF-8"?><web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"> <welcome-file-list> <welcome-file>index.jsp</welcome-file> </welcome-file-list> <filter> <filter-name>struts2</filter-name> <filter-class> org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter </filter-class> </filter> <filter-mapping> <filter-name>struts2</filter-name> <url-pattern>/*</url-pattern> </filter-mapping></web-app>
四個頁面：login.jsp list.jsp insert.jsp,update.jsp
login.jsp
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <base href="<%=basePath%>"> <title>My JSP 'login.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <a href="list.action">首頁</a>|<a href="insert.jsp">注冊</a> <form action="login.action" method="post"> <table> <tr> <td> 用戶名：</td><td><input name="user.name" type="text"></td> </tr> <tr> <td> 密碼：</td><td><input type="password" name="user.pwd"></td> </tr> <tr> <td colspan="2" align="center"><input type="submit" value="登錄"></td> </tr> </table> </form> </body></html>
list.jsp
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%><%@ taglib uri="/struts-tags" prefix="s"%><%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <base href="<%=basePath%>"> <title>My JSP 'list.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body > <a href="insert.jsp">注冊</a> <table border="1"> <tr> <td align="center" colspan="6"><font size="+3">用戶列表</font></td> </tr> <tr> <td>序號</td><td>用戶名</td><td>密碼</td><td>郵箱</td><td>刪除</td><td>編輯</td> </tr> <c:forEach items="${USER}" var="u" varStatus="temp"> <tr> <td>${temp.index+1}</td><td>${u.name }</td><td>${u.pwd }</td><td>${u.email}</td><td><a href="delete.action?uName=${u.name}">刪除</a></td><td><a href="edit.action?uName=${u.name }">編輯</a></td> </tr> </c:forEach> </table> </body></html>insert.jsp
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%><% String path = request.getContextPath(); String basePath = request.getScheme() + "://" + request.getServerName() + ":" + request.getServerPort() + path + "/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <base href="<%=basePath%>"> <title>My JSP 'register.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <a href="list.action">首頁</a> <form action="insert.action" method="post"> <table> <tr> <td> 用戶名： </td> <td> <input name="user.name" type="text"> </td> </tr> <tr> <td> 密碼： </td> <td> <input type="password" name="user.pwd"> </td> </tr> <tr> <td> 郵箱： </td> <td> <input type="text" name="user.email"> </td> </tr> <tr> <td colspan="2" align="center"> <input type="submit" value="提交"> </td> </tr> </table> </form> </body></html>
update.jsp
<%@ page language="java" import="java.util.*" pageEncoding="GBK"%><%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %><%String path = request.getContextPath();String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";%><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"><html> <head> <base href="<%=basePath%>"> <title>My JSP 'update.jsp' starting page</title> <meta http-equiv="pragma" content="no-cache"> <meta http-equiv="cache-control" content="no-cache"> <meta http-equiv="expires" content="0"> <meta http-equiv="keywords" content="keyword1,keyword2,keyword3"> <meta http-equiv="description" content="This is my page"> <!-- <link rel="stylesheet" type="text/css" href="styles.css"> --> </head> <body> <a href="list.action">首頁</a> <h2>更新操作</h2> <form action="update.action" method="post"> <table> <c:set value="${USER}" var="user"></c:set> <tr> <td> 用戶名：</td><td><input readonly="readonly" name="user.name" value="${user.name}" type="text"></td> </tr> <tr> <td> 密碼：</td><td><input type="password" value="${user.pwd }" name="user.pwd"></td> </tr> <tr> <td> 郵箱：</td><td><input type="text" value="${user.email }" name="user.email"></td> </tr> <tr> <td colspan="2" align="center"><input type="submit" value="保存"></td> </tr> </table> </form> </body></html>本人學習所用的user.xml文件
<?xml version="1.0" encoding="UTF-8"?><users><user email=aaa@sina.com name="bbb" pwd="aaaaaa"/><user email=bbb@sina.com name="ccc" pwd="aaaaaa"/></users>
希望本文所述對大家jsp程序設計有所幫助。
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