1.技术架构：三层架构--mvc
M: model V:View C:Controller
2.建立项目所使用的包：
bean: JavaBean
dao ：Dao接口
dao.impl: Dao接口的实现
service:业务接口（注册，登录）
service.impl: 业务接口的实现
web：Servlet控制器，处理页面的数据
工作流程：
User.java 定义了user的属性
package kangjie.bean;
import java.io.Serializable;
import java.util.Date;
public class User implements Serializable{
private String username;
private String password;
private String email;
private Date birthday; //date类型
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 getEmail() {
return email;
}
public void setEmail(String email) {
this.email = email;
}
public Date getBirthday() {
return birthday;
}
public void setBirthday(Date birthday) {
this.birthday = birthday;
}
}
UserDao接口
package kangjie.dao;
import kangjie.bean.User;
public interface UserDao {
/**
* 根据用户名和密码查询用户
* @param username
* @param password
* @return 查询到，返回此用户，否则返回null
*/
public User findUserByUserNameAndPassword(String username, String password);
/**
* 注册用户
* @param user 要注册的用户
*/
public void add(User user);
/**
* 更加用户名查找用户
* @param name
* @return查询到了则返回此用户，否则返回null
*/
public User findUserByUserName(String username);
}
UserDaoImpl dao接口的实现
package kangjie.dao.impl;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import kangjie.bean.User;
import kangjie.dao.UserDao;
import kangjie.utils.JaxpUtils;
import org.dom4j.Document;
import org.dom4j.Element;
import org.dom4j.Node;
public class UserDaoImpl implements UserDao {
/**
* 需要从xml文件中读取数据，需要一个类JaxpUtils.java
*/
@Override
public User findUserByUserNameAndPassword(String username, String password) {
//加载dom树
Document document = JaxpUtils.getDocument();
//查询需要的node节点
Node node = document.selectSingleNode("//user[@username=‘" + username + "‘ and @password=‘" + password + "‘]");
if(node != null){
//find him 封装数据
User user = new User();
user.setUsername(username);
user.setPassword(password);
user.setEmail(node.valueOf("@email"));
String birthday = node.valueOf("@birthday");
Date date;
try {
date = new SimpleDateFormat("yyyy-MM-dd").parse(birthday); //日期类型的转化
user.setBirthday(date);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return user;
}
return null;
}
@Override
public void add(User user) {
//加载dom树
Document document = JaxpUtils.getDocument();
//拿到根节点
Element root = document.getRootElement();
//添加一个user节点
root.addElement("user").addAttribute("username", user.getUsername())
.addAttribute("password", user.getPassword())
.addAttribute("email", user.getEmail())
.addAttribute("birthday", new SimpleDateFormat("yyyy-MM-dd").format(user.getBirthday())) ;
//将dom树报错到硬盘上
JaxpUtils.write2xml(document);
}
@Override
public User findUserByUserName(String username) {
//加载dom树
Document document = JaxpUtils.getDocument();
//查询需要的node节点
Node node = document.selectSingleNode("//user[@username=‘" + username + "‘]");
if(node != null){
//find him 封装数据
User user = new User();
user.setUsername(username);
user.setPassword(node.valueOf("@password"));
user.setEmail(node.valueOf("@email"));
String birthday = node.valueOf("@birthday");
Date date;
try {
date = new SimpleDateFormat("yyyy-MM-dd").parse(birthday);
user.setBirthday(date);
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return user;
}
return null;
}
}
UserService 业务逻辑接口
package kangjie.service;
import kangjie.bean.User;
import kangjie.exception.UserExistsException;
public interface UserService {
/**
* 根据用户名和密码
* @param username
* @param password
* @return 登录成功返回次用户，否则返回null
*/
public User login(String username, String password);
/**
* 用户注册
* @param user
* @return
*/
public void register(User user) throws UserExistsException; //注册失败时，抛出异常，由该类来处理
}
UserExistsException 接手异常
package kangjie.exception;
public class UserExistsException extends Exception{
}
UserServiceImpl 业务逻辑接口的实现
package kangjie.service.imple;
import kangjie.bean.User;
import kangjie.dao.UserDao;
import kangjie.dao.impl.UserDaoImpl;
import kangjie.exception.UserExistsException;
import kangjie.service.UserService;
public class UserServiceImpl implements UserService {
UserDao dao = new UserDaoImpl();
@Override
public User login(String username, String password) {
// TODO Auto-generated method stub
return dao.findUserByUserNameAndPassword(username, password);
}
@Override
public void register(User user) throws UserExistsException {
// 注册成功与否，可以去servlet里去抓异常
User u = dao.findUserByUserName(user.getUsername());
if(u == null){
dao.add(user);
}else{
throw new UserExistsException();
}
}
}
RegisterServlet 用户注册请求的处理
package kangjie.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import java.lang.reflect.InvocationTargetException;
import java.util.Date;
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 org.apache.commons.beanutils.ConvertUtils;
import org.apache.commons.beanutils.locale.converters.DateLocaleConverter;
import kangjie.bean.User;
import kangjie.exception.UserExistsException;
import kangjie.service.UserService;
import kangjie.service.imple.UserServiceImpl;
import kangjie.utils.WebUtils;
import kangjie.web.formbean.UserFormBean;
public class ResigterServlet extends HttpServlet {
/**
* 完成注册功能
*
* This method is called when a form has its tag value method equals to get.
*/
public void doGet(HttpServletRequest request, HttpServletResponse response)
throws ServletException, IOException {
//中文处理
request.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=utf-8");
PrintWriter writer = response.getWriter();
//先拿到数据,将数据封装到userformbean中，因为可能会有很多的bean，所以此处应该新创建一个类来处理这个问题
//WebUtils类，专门 封装数据
String username = request.getParameter("username");
System.out.println("---username---" + username);
UserFormBean ufb = WebUtils.fillFormBean(UserFormBean.class, request);
//第二步，验证数据
if(ufb.validate()){
//验证通过
//第三步，将formbean中的内容拷贝到user中
User user = new User();
//由于formbean中的生日是date类型，beanUtils类中不能自动转换，因此需要注册一个日期类型的转换器
//BeanUtils.copy将一个对象拷贝到另一个对象中去
try {
ConvertUtils.register(new DateLocaleConverter(), Date.class);
BeanUtils.copyProperties(user, ufb);
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
//第四步，注册用户
//调用业务逻辑层，完成注册
UserService us = new UserServiceImpl();
try {
us.register(user);
System.out.println("注册成功");
//注册成功
//将用户存入session对象中
// request.getSession().setAttribute("loginuser", user);
//返回登录页面
//最好采用请求重定向，（请求转发和请求重定向有什么区别）
//重定向和转发有一个重要的不同：当使用转发时，JSP容器将使用一个内部的方法来调用目标页面，新的页面继续处理同一个请求，
// 而浏览器将不会知道这个过程。 与之相反，重定向方式的含义是第一个页面通知浏览器发送一个新的页面请求。
// 因为，当你使用重定向时，浏览器中所显示的URL会变成新页面的URL, 而当使用转发时，该URL会保持不变。
// 重定向的速度比转发慢，因为浏览器还得发出一个新的请求。同时，由于重定向方式产生了一个新的请求，
// 所以经过一次重 定向后，request内的对象将无法使用。
// response.sendRedirect(request.getContextPath() + "/login.jsp");
//注册成功，提示用户
response.getWriter().write("注册成功，2秒后转向登录页面");
response.setHeader("Refresh", "2;url=" + request.getContextPath() + "/login.jsp");
} catch (UserExistsException e) {
// 说明用户已经注册过了
ufb.getErrors().put("username", "此用户已经被注册过了");
//将ufb存入request对象中
request.setAttribute("user", ufb);
request.getRequestDispatcher("/register.jsp").forward(request, response);
}
}else{
//验证失败
//打回去，同事把他原来填写的数据回写过去
//把ufb对象存入request对象
request.setAttribute("user", ufb);
//给页面传递的就是user对象，则在页面上显示的候，需要从user对象中拿取该数据
request.getRequestDispatcher("/register.jsp").forward(request, response);
}
}
/**
* 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 {
doGet(request, response);
}
}
loginServlet 处理用户登录请求
package kangjie.servlet;
import java.io.IOException;
import java.io.PrintWriter;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import kangjie.bean.User;
import kangjie.service.UserService;
import kangjie.service.imple.UserServiceImpl;
public class loginServlet 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 {
request.setCharacterEncoding("UTF-8");
response.setContentType("text/html;charset=UTF-8");
PrintWriter out = response.getWriter();
//获取页面数据
String username = request.getParameter("username");
String password = request.getParameter("password");
System.out.println("---username---"+ username + "---password---" +password);
//验证数据
UserService user = new UserServiceImpl();
User u = user.login(username, password);
if(u != null){
//合法用户
request.getSession().setAttribute("loginuser", u);
request.getRequestDispatcher("/main.jsp").forward(request, response);
}else{
//非法用户
System.out.println("**用户名或密码错误**");
request.getSession().setAttribute("error", "用户名或密码错误");
response.sendRedirect(request.getContextPath() + "/servlet/login.jsp");
}
}
/**
* 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 {
doGet(request, response);
}
}
JaxpUtils 处理xml文件的类，使用xml文件来充当数据库
package kangjie.utils;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.OutputStream;
import java.io.UnsupportedEncodingException;
import org.dom4j.Document;
import org.dom4j.DocumentException;
import org.dom4j.io.OutputFormat;
import org.dom4j.io.SAXReader;
import org.dom4j.io.XMLWriter;
//操作XML文件的方法
public class JaxpUtils {
static String path;
static {
System.out.println("---getpath----");
path = JaxpUtils.class.getClassLoader().getResource("users.xml").getPath();
System.out.println("---path---" + path);
}
public static Document getDocument(){
//创建一个dom4j的解析器
try {
SAXReader sx = new SAXReader();
Document doc = sx.read(path);
return doc;
} catch (DocumentException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return null;
}
public static void write2xml(Document document){
try {
XMLWriter writer = new XMLWriter(new FileOutputStream(path), OutputFormat.createPrettyPrint());
writer.write(document);
writer.close();
} catch (UnsupportedEncodingException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
WebUtils 封装页面的数据
package kangjie.utils;
import java.lang.reflect.InvocationTargetException;
import javax.servlet.http.HttpServletRequest;
import org.apache.commons.beanutils.BeanUtils;
//为页面服务，封装页面的数据
public class WebUtils {
//写一个泛型
public static <T> T fillFormBean(Class<T> clazz,HttpServletRequest request){
T t = null;
try {
t = clazz.newInstance();//反射机制
BeanUtils.populate(t, request.getParameterMap());
} catch (InstantiationException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IllegalAccessException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (InvocationTargetException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
return t;
}
}
UserFormBean 用来封装页面数据
package kangjie.web.formbean;
import java.text.ParseException;
import java.util.HashMap;
import java.util.Map;
import org.apache.commons.beanutils.locale.converters.DateLocaleConverter;
/**
* 为什么要UserFormBean
* 是因为页面上的数据类型很多，与user不匹配，所以需要UserFormBean
* @author kj
*
*/
public class UserFormBean {
private String username;
private String password;
private String repassword;
private String email;
private String 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 getRepassword() {
return repassword;
}
public void setRepassword(String repassword) {
this.repassword = repassword;
}
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;
}
/**
* 验证数据
* 服务端验证必须要有
* @return
*/
public boolean validate(){
//验证用户名
if(username == "" || username == null){
errors.put("username", "用户名或密码不能为空");
}else{
if(username.length() <3 || username.length() > 11){
errors.put("username", "用户名长度在3-8之间");
}
}
if(password == "" || password == null){
errors.put("password", "用户名或密码不能为空");
}else{
if(password.length() <3 || password.length() > 11){
errors.put("password", "密码长度在3-8之间");
}
}
//验证重复密码
if(!repassword.equals(password)){
errors.put("repassword", "两次密码输入不一致");
}
//验证邮箱
if(email == "" || email == null){
errors.put("email", "邮箱不能为空");
}else{
if(!email.matches("^([a-zA-Z0-9_\\-\\.]+)@((\\[[0-9]{1,3}\\.[0-9]{1,3}\\.[0-9]{1,3}\\.)|(([a-zA-Z0-9\\-]+\\.)+))([a-zA-Z]{2,4}|[0-9]{1,3})(\\]?)$")) {
errors.put("email", "邮箱格式不正确");
}
}
//验证生日
if(birthday == "" || birthday == null){
errors.put("birthday", "生日不能为空");
}else{
//验证日期存在缺陷：2-30日不能验证,需要使用另外一个类：
// -----DateLocalConverter---apache
// SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd");
DateLocaleConverter dlc = new DateLocaleConverter();
try {
dlc.convert(birthday);
} catch (Exception e) {
// TODO Auto-generated catch block
errors.put("birthday", "日期格式错误");
}
}
//如果errors为空，说明没有错误产生
return errors.isEmpty();
//userbean写好了，下边就开始写Servlet
}
//存放错误信息，使用Map，一对.然后只需要提供map的get方法即可
private Map<String,String> errors = new HashMap<String, String>();
public Map<String, String> getErrors() {
return errors;
}
}
users.xml文件
<?xml version="1.0" encoding="UTF-8"?>
<users>
<user username="陈紫函" password="123" email="[email protected]" birthday="1980-10-10"/>
</users>
register.jsp 注册页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>register.jsp</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
<form action="${pageContext.request.contextPath}/servlet/ResigterServlet" method="post">
<table border="8">
<tr>
<td>姓名</td>
<td><input type="text" name="username" value="${user.username }"></td> <!-- value 用来回显数据 -->
<td>${user.errors.username }</td>
</tr>
<tr>
<td>密码</td>
<td><input type="password" name="password" value="${user.password }"></td>
<td>${user.errors.password }</td>
</tr>
<tr>
<td>确认密码</td>
<td><input type="password" name="repassword" value="${user.repassword }"></td>
<td>${user.errors.repassword }</td>
</tr>
<tr>
<td>邮箱</td>
<td><input type="text" name="email" value="${user.email }"></td>
<td>${user.errors.email }</td>
</tr>
<tr>
<td>生日</td>
<td><input type="text" name="birthday" value="${user.birthday }"></td>
<td>${user.errors.birthday }</td>
</tr>
<tr>
<td colspan="3" align="center"><input type="submit" value="注册 "></td>
</tr>
</table>
</form>
</body>
</html>
login.jsp 登录页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
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>登录</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>
<form action="${pageContext.request.contextPath }/servlet/loginServlet">
用户名：<input type="text" name="username"><br><br>
密 码： <input type="password" name="password"><br><br>
<input type="submit" value="登录"><br>
</form>
</body>
</html>
main.jsp 主页面
<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%>
<%
String path = request.getContextPath();
String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";
%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<base href="<%=basePath%>">
<title>欢迎登录</title>
<meta http-equiv="pragma" content="no-cache">
<meta http-equiv="cache-control" content="no-cache">
<meta http-equiv="expires" content="0">
<meta http-equiv="keywords" content="keyword1,keyword2,keyword3">
<meta http-equiv="description" content="This is my page">
<!--
<link rel="stylesheet" type="text/css" href="styles.css">
-->
</head>
<body>
欢迎回来！${loginuser.username}
</body>
</html>
时间： 2024-11-10 10:48:07