Java Web 案例一 登录、注册功能实现
实现用户登录和注册功能。项目分为 Web 层、业务逻辑层、数据访问层。
将用户信息封装在 UserBean 对象中。用户信息有：username(String)、password(String)、nickname(String)、email(String)、birthday(Date)。
在注册页面设计时，我们应考虑用户输入数据的合法性，所以我们将用户输入的表单数据封装在 FormBean 中，由于用户提交的数据都是以字符串的形式传递，因此 FormBean 中的所有对象都是 String 类型。在 FormBean 中还维护了一个 Map 对象，用以存放错误提示信息。如果用户输入的数据不合法，我们可以将错误信息作为 value 将表单项的名作为 key 存放在 Map 中，再以 request 属性的方式转发给注册页面，实现动态错误提示功能。为了防止机器人注册，我们还应该在注册页面中加入验证码。生成验证码的 Servlet 作为工具类存放在 utils 包中。服务器产生的验证码数据存放在服务器 session 对象中，用以用户提交表单时验证。为了防止 表单重复提交，我们在表单中还应该增加一个表单令牌，以隐藏域的形式存放。同样服务器的 session 对象中也应该增加这个属性。
当用户提交注册请求的时候，我们利用 BeanUtils 的 populate 方法，将请求数据存放在 FormBean 中，如果验证合法，那么我们再将 FormBean 中的数据拷贝到 UserBean 中存储。在拷贝 Bean 对象时，我们利用 BeanUtils 的 copyBean 方法，将一个对象中的属性拷贝到另一个对象。注意，因为 FormBean 中的属性都是 String 类型，而 UserBean 中的生日是以 Date 类型存储，因此我们在拷贝属性时应该自定义一个转换器。在数据库中存储的用户密码应该是以 MD5 方式加密后的数据，我们在存储用户名密码时应该先用 MD5 运算后再存入数据库。
用户登录页面提交数据到 LoginServlet 时，我们先将提交的密码数据进行 MD5 运算，然后与数据库中的密码进行比对。如果比对成功，则在 Session 域中存储用户信息，再跳转至首页。如果比对失败则将错误信息存放在 request 域中带给客户机进行提示。
业务逻辑图：
包层次关系：
cn.dk.domain
package cn.dk.domain;
import java.util.Date;
public class User {
public User() {
super();
}
public User(String username, String password, String nickname,
String email, Date birthday) {
super();
this.username = username;
this.password = password;
this.nickname = nickname;
this.email = email;
this.birthday = birthday;
}
private String username;
private String password;
private String nickname;
private String email;
private Date birthday;
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getNickname() {
return nickname;
}
public void setNickname(String nickname) {
this.nickname = nickname;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
}
cn.dk.dao
package cn.dk.dao;
import cn.dk.domain.User;
public interface IUserDao {
public void insertUser(User user);
public boolean seacherUserByUsername(String username);
public User searchUser(String username, String password);
}
package cn.dk.dao.impl;
import java.security.MessageDigest;
import java.security.NoSuchAlgorithmException;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.Node;
import com.sun.org.apache.xerces.internal.impl.dv.util.Base64;
import cn.dk.dao.IUserDao;
import cn.dk.domain.User;
import cn.dk.utils.XmlUtils;
public class UserDaoImpl implements IUserDao {
public void insertUser(User user) {
// 获取xml文档对象
Document document = XmlUtils.getDocument();
// 获取文档根元素
Element root = document.getRootElement();
// 向根元素中增加子元素
Element child = root.addElement("user");
// 向子元素中增加用户名和密码属性
child.addAttribute("username", user.getUsername());
// 对密码加密
String disgestPass = this.md5Disgest(user.getPassword());
child.addAttribute("password", disgestPass);
// 向子元素中增加昵称、email、生日属性
child.addElement("nickname").addText(user.getNickname());
child.addElement("email").addText(user.getEmail());
if (user.getBirthday() != null) {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
String birthday = format.format(user.getBirthday());
child.addElement("birthday").addText(birthday);
}
// 保存xml到磁盘
XmlUtils.saveXml(document);
}
public User searchUser(String username, String password) {
// 获取xml文档对象
Document document = XmlUtils.getDocument();
// 获取文档根元素
Element root = document.getRootElement();
// 对密码进行md5运算
String disgestPass = this.md5Disgest(password);
// 匹配用户名和密码
Element child = (Element) root.selectSingleNode("//user[@username='"
+ username + "' and @password='" + disgestPass + "']");
User user = null;
if (child != null) {
user = new User();
user.setUsername(child.attributeValue("username"));
user.setPassword(child.attributeValue("password"));
user.setNickname(child.elementText("nickname"));
user.setEmail(child.attributeValue("email"));
String birthdayStr = child.attributeValue("birthday");
if (birthdayStr != null) {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
try {
Date birthday = format.parse(child
.attributeValue("birthday"));
user.setBirthday(birthday);
} catch (ParseException e) {
throw new RuntimeException(e);
}
}
}
return user;
}
public boolean seacherUserByUsername(String username) {
// 获取xml文档对象
Document document = XmlUtils.getDocument();
// 获取文档根元素
Element root = document.getRootElement();
// 匹配用户名
Node selectSingleNode = root.selectSingleNode("//user[@username='"
+ username + "']");
if (selectSingleNode != null)
return true;
return false;
}
private String md5Disgest(String key) {
try {
MessageDigest disDigest = MessageDigest.getInstance("md5");
byte[] digest = disDigest.digest(key.getBytes());
String base = Base64.encode(digest);
return base.substring(0, base.length() - 1);
} catch (NoSuchAlgorithmException e) {
throw new RuntimeException(e);
}
}
}
cn.dk.service
package cn.dk.service;
import cn.dk.domain.User;
public interface IServiceDao {
public void insertUser(User user);
public boolean searchUserByUsername(String username);
public User searchUser(String username, String password);
}
package cn.dk.service.impl;
import cn.dk.dao.impl.UserDaoImpl;
import cn.dk.domain.User;
import cn.dk.service.IServiceDao;
public class ServiceImpl implements IServiceDao {
private UserDaoImpl userDao = new UserDaoImpl();
public void insertUser(User user) {
userDao.insertUser(user);
}
public User searchUser(String username, String password) {
return userDao.searchUser(username, password);
}
public boolean searchUserByUsername(String username) {
return userDao.seacherUserByUsername(username);
}
}
cn.dk.web.control
package cn.dk.web.control;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class LoginOut extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.getSession().removeAttribute("user");
request.getRequestDispatcher("/index.jsp").forward(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package cn.dk.web.control;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import cn.dk.domain.User;
import cn.dk.service.impl.ServiceImpl;
@SuppressWarnings("serial")
public class LoginServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
ServiceImpl service = new ServiceImpl();
String username = request.getParameter("username");
String password = request.getParameter("password");
System.out.println(password);
User user = service.searchUser(username, password);
if(user != null){
response.sendRedirect(request.getContextPath() + "/index.jsp");
}else{
request.setAttribute("message", "用户名或密码错误");
request.getRequestDispatcher("/WEB-INF/pages/login.jsp").forward(request, response);
}
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package cn.dk.web.control;
import java.io.IOException;
import java.util.Map;
import java.util.UUID;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.commons.beanutils.BeanUtils;
import cn.dk.domain.User;
import cn.dk.service.impl.ServiceImpl;
import cn.dk.utils.FormUtils;
import cn.dk.utils.ServletUtils;
@SuppressWarnings("serial")
public class RegisterServlet extends HttpServlet {
@SuppressWarnings("unchecked")
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
String userFormId = request.getParameter("formid");
String sessionFormId = request.getSession().getAttribute("formid").toString();
if (sessionFormId != null) {
if (userFormId.equals(sessionFormId)) {
request.getSession().removeAttribute("formid");
Map params = request.getParameterMap();
FormUtils formBean = new FormUtils();
try {
BeanUtils.populate(formBean, params);
boolean success = formBean.validate(request);
if (!success) {
request.setAttribute("error", formBean.getErrors());
UUID randomUUID = UUID.randomUUID();
request.setAttribute("formid", randomUUID.toString());
request.getSession().setAttribute("formid",
randomUUID.toString());
request.getRequestDispatcher(
"/WEB-INF/pages/register.jsp").forward(request,
response);
} else {
ServiceImpl service = new ServiceImpl();
User user = new User();
ServletUtils.copyBean(formBean, user);
service.insertUser(user);
request.getSession().setAttribute("user", user);
request.setAttribute("message",
"注册成功！浏览器将在 3 秒内跳转到首页...
cn.dk.web.UI
package cn.dk.web.UI;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class Indx extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.getRequestDispatcher("/index.jsp").forward(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package cn.dk.web.UI;
import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class LoginServletUI extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
request.getRequestDispatcher("/WEB-INF/pages/login.jsp").forward(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package cn.dk.web.UI;
import java.io.IOException;
import java.util.UUID;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class RegisterServletUI extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
UUID randomUUID = UUID.randomUUID();
request.setAttribute("formid", randomUUID.toString());
request.getSession().setAttribute("formid", randomUUID.toString());
request.getRequestDispatcher("/WEB-INF/pages/register.jsp").forward(request, response);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
cn.dk.utils
package cn.dk.utils;
import java.awt.Color;
import java.awt.Font;
import java.awt.Graphics;
import java.awt.image.BufferedImage;
import java.io.IOException;
import java.util.Random;
import javax.imageio.ImageIO;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
@SuppressWarnings("serial")
public class CreateImgServlet extends HttpServlet {
private static final int WIDTH = 130;
private static final int HEIGHT = 30;
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
// 创建一张图片
BufferedImage image = new BufferedImage(WIDTH, HEIGHT,
BufferedImage.TYPE_INT_RGB);
// 创建画板
Graphics g = image.getGraphics();
// 填充背景色
this.fillBackcolor(g);
// 画边框
this.drawRect(g);
// 画干扰线
this.drawLine(g);
// 画文字
this.drawWrod(g, request);
// 创建图片输出流
response.setContentType("image/gif");
response.setDateHeader("Expries", -1);
response.setHeader("Pragma", "no-cache");
response.setHeader("Cache-Control", "no-cache");
ImageIO.write(image, "jpeg", response.getOutputStream());
g.dispose();
}
private void drawWrod(Graphics g, HttpServletRequest request) {
g.setColor(Color.YELLOW);
g.setFont(new Font("黑体", Font.BOLD, 18));
String words = "\u7684\u4e00\u4e86\u662f\u6211\u4e0d\u5728\u4eba\u4eec\u6709\u6765\u4ed6\u8fd9\u4e0a\u7740\u4e2a\u5730\u5230\u5927\u91cc\u8bf4\u5c31\u53bb\u5b50\u5f97\u4e5f\u548c\u90a3\u8981\u4e0b\u770b\u5929\u65f6\u8fc7\u51fa\u5c0f\u4e48\u8d77\u4f60\u90fd\u628a\u597d\u8fd8\u591a\u6ca1\u4e3a\u53c8\u53ef\u5bb6\u5b66\u53ea\u4ee5\u4e3b\u4f1a\u6837\u5e74\u60f3\u751f\u540c\u8001\u4e2d\u5341\u4ece\u81ea\u9762\u524d\u5934\u9053\u5b83\u540e\u7136\u8d70\u5f88\u50cf\u89c1\u4e24\u7528\u5979\u56fd\u52a8\u8fdb\u6210\u56de\u4ec0\u8fb9\u4f5c\u5bf9\u5f00\u800c\u5df1\u4e9b\u73b0\u5c71\u6c11\u5019\u7ecf\u53d1\u5de5\u5411\u4e8b\u547d\u7ed9\u957f\u6c34\u51e0\u4e49\u4e09\u58f0\u4e8e\u9ad8\u624b\u77e5\u7406\u773c\u5fd7\u70b9\u5fc3\u6218\u4e8c\u95ee\u4f46\u8eab\u65b9\u5b9e\u5403\u505a\u53eb\u5f53\u4f4f\u542c\u9769\u6253\u5462\u771f\u5168\u624d\u56db\u5df2\u6240\u654c\u4e4b\u6700\u5149\u4ea7\u60c5\u8def\u5206\u603b\u6761\u767d\u8bdd\u4e1c\u5e2d\u6b21\u4eb2\u5982\u88ab\u82b1\u53e3\u653e\u513f\u5e38\u6c14\u4e94\u7b2c\u4f7f\u5199\u519b\u5427\u6587\u8fd0\u518d\u679c\u600e\u5b9a\u8bb8\u5feb\u660e\u884c\u56e0\u522b\u98de\u5916\u6811\u7269\u6d3b\u90e8\u95e8\u65e0\u5f80\u8239\u671b\u65b0\u5e26\u961f\u5148\u529b\u5b8c\u5374\u7ad9\u4ee3\u5458\u673a\u66f4\u4e5d\u60a8\u6bcf\u98ce\u7ea7\u8ddf\u7b11\u554a\u5b69\u4e07\u5c11\u76f4\u610f\u591c\u6bd4\u9636\u8fde\u8f66\u91cd\u4fbf\u6597\u9a6c\u54ea\u5316\u592a\u6307\u53d8\u793e\u4f3c\u58eb\u8005\u5e72\u77f3\u6ee1\u65e5\u51b3\u767e\u539f\u62ff\u7fa4\u7a76\u5404\u516d\u672c\u601d\u89e3\u7acb\u6cb3\u6751\u516b\u96be\u65e9\u8bba\u5417\u6839\u5171\u8ba9\u76f8\u7814\u4eca\u5176\u4e66\u5750\u63a5\u5e94\u5173\u4fe1\u89c9\u6b65\u53cd\u5904\u8bb0\u5c06\u5343\u627e\u4e89\u9886\u6216\u5e08\u7ed3\u5757\u8dd1\u8c01\u8349\u8d8a\u5b57\u52a0\u811a\u7d27\u7231\u7b49\u4e60\u9635\u6015\u6708\u9752\u534a\u706b\u6cd5\u9898\u5efa\u8d76\u4f4d\u5531\u6d77\u4e03\u5973\u4efb\u4ef6\u611f\u51c6\u5f20\u56e2\u5c4b\u79bb\u8272\u8138\u7247\u79d1\u5012\u775b\u5229\u4e16\u521a\u4e14\u7531\u9001\u5207\u661f\u5bfc\u665a\u8868\u591f\u6574\u8ba4\u54cd\u96ea\u6d41\u672a\u573a\u8be5\u5e76\u5e95\u6df1\u523b\u5e73\u4f1f\u5fd9\u63d0\u786e\u8fd1\u4eae\u8f7b\u8bb2\u519c\u53e4\u9ed1\u544a\u754c\u62c9\u540d\u5440\u571f\u6e05\u9633\u7167\u529e\u53f2\u6539\u5386\u8f6c\u753b\u9020\u5634\u6b64\u6cbb\u5317\u5fc5\u670d\u96e8\u7a7f\u5185\u8bc6\u9a8c\u4f20\u4e1a\u83dc\u722c\u7761\u5174\u5f62\u91cf\u54b1\u89c2\u82e6\u4f53\u4f17\u901a\u51b2\u5408\u7834\u53cb\u5ea6\u672f\u996d\u516c\u65c1\u623f\u6781\u5357\u67aa\u8bfb\u6c99\u5c81\u7ebf\u91ce\u575a\u7a7a\u6536\u7b97\u81f3\u653f\u57ce\u52b3\u843d\u94b1\u7279\u56f4\u5f1f\u80dc\u6559\u70ed\u5c55\u5305\u6b4c\u7c7b\u6e10\u5f3a\u6570\u4e61\u547c\u6027\u97f3\u7b54\u54e5\u9645\u65e7\u795e\u5ea7\u7ae0\u5e2e\u5566\u53d7\u7cfb\u4ee4\u8df3\u975e\u4f55\u725b\u53d6\u5165\u5cb8\u6562\u6389\u5ffd\u79cd\u88c5\u9876\u6025\u6797\u505c\u606f\u53e5\u533a\u8863\u822c\u62a5\u53f6\u538b\u6162\u53d4\u80cc\u7ec6";
Random random = new Random();
StringBuffer sb = new StringBuffer();
int x = 15;
for (int i = 0; i < 4; i++) {
String word = words.charAt(random.nextInt(words.length())) + "";
sb.append(word);
g.drawString(word, x, 20);
x += 30;
}
request.getSession().setAttribute("validateImg", sb.toString());
}
private void drawLine(Graphics g) {
g.setColor(Color.RED);
int x = 0;
int _x = 0;
int y = 0;
int _y = 0;
Random random = new Random();
for (int i = 0; i < 5; i++) {
x = random.nextInt(WIDTH);
y = random.nextInt(HEIGHT);
_x = random.nextInt(WIDTH);
_y = random.nextInt(HEIGHT);
g.drawLine(x, y, _x, _y);
}
}
private void drawRect(Graphics g) {
g.setColor(Color.BLUE);
g.drawRect(1, 1, WIDTH - 2, HEIGHT - 2);
}
private void fillBackcolor(Graphics g) {
g.setColor(Color.green);
g.fillRect(0, 0, WIDTH, HEIGHT);
}
public void doPost(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
doGet(request, response);
}
}
package cn.dk.utils;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.HashMap;
import java.util.Map;
import javax.servlet.http.HttpServletRequest;
import cn.dk.service.impl.ServiceImpl;
public class FormUtils {
public FormUtils() {
super();
this.errors = new HashMap();
}
private String username;
private String password;
private String rePassword;
private String nickname;
private String email;
private String birthday;
private String validateTxt;
private Map errors;
public String getValidateTxt() {
return validateTxt;
}
public void setValidateTxt(String validateTxt) {
this.validateTxt = validateTxt;
}
public String getUsername() {
return username;
}
public void setUsername(String username) {
this.username = username;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getRePassword() {
return rePassword;
}
public void setRePassword(String rePassword) {
this.rePassword = rePassword;
}
public String getNickname() {
return nickname;
}
public void setNickname(String nickname) {
this.nickname = nickname;
}
public String getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public String getBirthday() {
return birthday;
}
public void setBirthday(String birthday) {
this.birthday = birthday;
}
public Map getErrors() {
return errors;
}
public void setErrors(Map errors) {
this.errors = errors;
}
public boolean validate(HttpServletRequest request) {
if (validateTxt == null || validateTxt.equals("")) {
errors.put("validateTxt", "验证码不能为空");
return false;
}
if (!request.getSession().getAttribute("validateImg").toString().equals(validateTxt)) {
errors.put("validateTxt", "验证码不正确");
return false;
}
if (username == null || username.trim().equals("")) {
errors.put("username", "用户名不能为空");
return false;
}
if (!username.matches("[a-zA-Z]{6,8}")) {
errors.put("username", "用户名只能是6-8位字母");
return false;
}
ServiceImpl service = new ServiceImpl();
if (service.searchUserByUsername(username)) {
errors.put("username", "用户名已存在");
return false;
}
if (password == null || password.trim().equals("")) {
errors.put("password", "密码不能为空");
return false;
}
if (password.matches("\\.{6,8}")) {
errors.put("password", "密码只能是6-8位字符");
return false;
}
if (!password.equals(rePassword)) {
errors.put("rePassword", "两次输入密码不一致");
return false;
}
if (nickname == null || nickname.trim().equals("")) {
errors.put("nickname", "昵称不能为空");
return false;
}
if (!nickname.matches("[\u4e00-\u9fa5]+")) {
errors.put("nickname", "昵称必须是中文");
return false;
}
if (email == null || email.trim().equals("")) {
errors.put("email", "邮箱不能为空");
return false;
}
if (!email.matches("\\w+@\\w+\\.\\w+(\\.\\w+)?")) {
errors.put("email", "邮箱格式不正确");
return false;
}
if (birthday != "") {
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
try {
Date parse = format.parse(birthday);
if (parse == null) {
errors.put("birthday", "出生日期格式不正确");
return false;
}
} catch (ParseException e) {
throw new RuntimeException(e);
}
}
return true;
}
}
package cn.dk.utils;
import java.text.SimpleDateFormat;
import java.util.Date;
import org.apache.commons.beanutils.BeanUtils;
import org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.Converter;
public class ServletUtils {
public static void copyBean(Object src, Object des) {
ConvertUtils.register(new Converter() {
@SuppressWarnings("unchecked")
public Object convert(Class arg0, Object type) {
if (type == null)
return null;
String date = (String) type;
if (date.trim().equals(""))
return null;
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
Date birthday = null;
try {
birthday = format.parse(date);
} catch (Exception e) {
e.printStackTrace();
}
return birthday;
}
}, Date.class);
try {
BeanUtils.copyProperties(des, src);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
package cn.dk.utils;
import java.io.File;
import java.io.FileOutputStream;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
public class XmlUtils {
/**
* 获取xml文档
*
* @return Dom4j 形式的Document文档对象
*/
public static Document getDocument() {
// 获取xml文件路径
String path = XmlUtils.class.getResource("/users.xml").getPath();
// 获取xml读取器
SAXReader reader = new SAXReader();
try {
// 解析xml文档，并返回Document文档模型
return reader.read(new File(path));
} catch (DocumentException e) {
throw new RuntimeException(e);
}
}
/**
* 将文档对象写入磁盘
*
* @param document
*/
public static void saveXml(Document document) {
// 获取xml文件路径
String path = XmlUtils.class.getResource("/users.xml").getPath();
// 获取格式化输出流
OutputFormat format = OutputFormat.createPrettyPrint();
// 获取xml输出流
XMLWriter writer;
try {
writer = new XMLWriter(new FileOutputStream(path), format);
writer.write(document);
} catch (Exception e) {
throw new RuntimeException(e);
}
}
}
XML
pages
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
用户登录
DK_用户登录
message.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
系统消息
${requestScope.message }
register.jsp
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
用户注册
DK_官网注册
Index
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%@taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
DK社区
DriverKing_