网站注册登录注销功能实现

回到学校已经有三个星期了，那也有三个星期没有去写博客了，今天就对之前学习的内容进行一个小的项目回顾一下吧。
今天要实现的项目是某网站里面的注册登录注销三个功能。
开发环境：Eclipse ,tomcat8.0,jdk1.8,mysql5.5。
导入的jar包：commons-beanutils-1.8.3.jar，commons-logging-1.1.1.jar，jstl.jar，mysql-connector-java-5.1.26-bin.jar，standard.jar。
做什么之前都需要去了解清楚需求。
1注册：用户输入用户名（3~8位字母组成），密码：（必须输入，3~8位数字组成），重复密码：（必须和密码一致），邮箱：（必须输入，且要符合邮箱的格式），出生日期：（必须输入，格式2001-03-18）。
2登录：输入用户名和密码，正确后会跳转会主页，并显示用户名在主页上。
3注销：点击注销后主页上不在显示用户名，并出现登录注册按钮。

那我们现在去编程吧。首先是写前端的代码:

index.jsp:

<%@ page language="java" contentType="text/html; charset=utf-8"pageEncoding="utf-8"%>
<%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c"%>
<%String path = request.getContextPath();%>
<!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>XXX</title>
<style type="text/css">
//编写样式后面的工作
*{margin:0;
padding:0;
}
body{
font-size:12px;
font-family:"微软雅黑";
}
a{color:blue;
text-decoration: none;
}
a:HOVER {color:red;
}</style>
</head><body>
XX网站<br/>
<c:if test="${sessionScope.user ==null }"><a href="<%=path %>/login.jsp">登录</a><a href="<%=path %>/regist.jsp">注册</a></c:if>
<c:if test="${sessionScope.user !=null }">欢迎<a href="">${sessionScope.user.username}</a>&nbsp; &nbsp; <a href="${pageContext.request.contextPath  }/servlet/LogoutServlet">注销</a>
</c:if>
</body>
</html>

regist.jsp:

<%@ page language="java" contentType="text/html; charset=utf-8"pageEncoding="utf-8"%><%@ taglib uri="http://java.sun.com/jsp/jstl/core" prefix="c" %>
<!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>XXX</title>
</head>
<body>
<form action="${pageContext.request.contextPath}/servlet/RegistServlet" method="post"><table border="1"><tr><th>用户名：(必须输入，3~8位字母组成)</th><td><input type="text" id="username" name="username"  value="${formbean.username }"/>${formbean.errors.username}</td></tr><tr><th>密码：（必须输入，3~8位数字组成）</th><td><input type="password" name="password" value="${formbean.password}"/>${formbean.errors.password}</td></tr><tr><th>重复密码：（必须和密码一致）</th><td><input type="password" name="repassword" value="${formbean.repassword}"/>${formbean.errors.repassword}</td></tr><tr><th>邮箱：（必须输入，且要符合邮箱的格式）</th><td><input type="text" name="email" value="${formbean.email}"/>${formbean.errors.email}</td></tr><tr><th>出生日期：（必须输入，格式2001-03-18）</th><td><input type="text" name="birthday" value="${formbean.birthday}" />${formbean.errors.birthday}</td></tr></table><input type="submit" value="注册" /></form>
</body>
</html>

<%@ page language="java" contentType="text/html; charset=utf-8"pageEncoding="utf-8"%>
<!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>登录页面</title>
</head>
<body>
<form action="${pageContext.request.contextPath}/servlet/LoginServlet" method="post"><table ><tr><th>账号：</th><td><input type="text"  name="username"></td></tr><tr><th>密码：</th><td><input type="text"  name="password"></td></tr></table><input type="submit" value="登录"/>
</form>
</body>
</html>

下面展示一下包结构：
wyxbs项目包结构
下面是后端代码：
top.wyxbs.domain包下的User.java

/*** 用户类* @author chenjingbin**/
public class User implements Serializable {private static final long serialVersionUID = 1L;/*** 用户名*/private String username;/*** 密码*/private String password;/*** 邮箱*/private String email;/*** 出生日期*/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 getEmail() {return email;}public void setEmail(String email) {this.email = email;}public Date getBirthday() {return birthday;}public void setBirthday(Date birthday) {this.birthday = birthday;}@Overridepublic String toString() {return "User [username=" + username + ", password=" + password + ", email=" + email + ", birthday=" + birthday+ "]";}}

top.wyxbs.util包下的类

/*** * 数据库帮助类* @author chenjingbin* @since 2017/3/16*/
public class DBHelper {private final static String URL = "jdbc:mysql://localhost:3306/wyxbs";private final static String DRIVER = "com.mysql.jdbc.Driver";private final static String USER = "wyxbsadmin";private final static String PASSWORD = "111111";static {try {Class.forName(DRIVER);} catch (ClassNotFoundException e) {// TODO Auto-generated catch blocke.printStackTrace();}}/*** * 获取Connection对象* @return Connection*/public static Connection getConnection() {Connection connection = null;try {connection = DriverManager.getConnection(URL, USER, PASSWORD);} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}return connection;}/*** 关闭流* @param connection * @param statement* @param resultSet* @throws SQLException*/public static void streamClose(Connection connection, Statement statement,ResultSet resultSet) throws SQLException {if (resultSet != null) {resultSet.close();}if (statement != null) {statement.close();}if (connection != null) {connection.close();}}}
//--------------------------------------------------
public class WebUtil {/*** 使用BeanUtils完成Javabean对象* @param request* @param class1 类的对象* @return*/public static <T> T fillBean(HttpServletRequest request,Class<T> class1){T t = null ;try {t = class1.newInstance();BeanUtils.populate(t, request.getParameterMap());} catch (InstantiationException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (IllegalAccessException e) {// TODO Auto-generated catch blocke.printStackTrace();} catch (InvocationTargetException e) {// TODO Auto-generated catch blocke.printStackTrace();}return t;   }
}

top.wyxbs.dao包下的类：

import top.wyxbs.domain.User;public interface UserDao {/*** 保存用户* @param user 用户对象*/void save(User user);/*** 查找用户根据用户名去找* @param name 用户名* @return 返回用户对象*/ User findUserByName(String name);/*** 根据账号密码去查找用户* @param name 用户名* @param password 密码* @return 返回符合的用户对象*/User findUser(String name ,String password); 
}
//-------------------------------------------------import java.sql.Connection;
import java.sql.Date;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;import top.wyxbs.domain.User;
import top.wyxbs.util.DBHelper;public class UserDaoImpl implements UserDao {@Overridepublic void save(User user) {// TODO Auto-generated method stubConnection connection = null;PreparedStatement prepareStatement = null ;String sql = "insert into t_user (username ,password,email,birthday) values(?,?,?,? );";try {connection = DBHelper.getConnection();//需要去转换java.util.date 转换为java.sql.date
//          Date date =new Date(user.getBirthday().getTime());//System.out.println(date);prepareStatement = connection.prepareStatement(sql);prepareStatement.setString(1, user.getUsername());prepareStatement.setString(2, user.getPassword());prepareStatement.setString(3, user.getEmail());prepareStatement.setDate(4, new Date(user.getBirthday().getTime()));prepareStatement.executeUpdate();} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally {try {DBHelper.streamClose(connection, prepareStatement, null);} catch (SQLException e) {// TODO Auto-generated catch blockSystem.out.println("关闭流出现问题");}}}@Overridepublic User findUserByName(String name) {// TODO Auto-generated method stubConnection connection = null;PreparedStatement prepareStatement = null;ResultSet resultSet =  null;String sql="select username,password,email,birthday from t_user where username=?";try {connection = DBHelper.getConnection();prepareStatement = connection.prepareStatement(sql);prepareStatement.setString(1, name);resultSet = prepareStatement.executeQuery();User user = new User();while(resultSet.next()){user.setUsername(resultSet.getString("username"));user.setPassword(resultSet.getString("password"));user.setEmail(resultSet.getString("email"));user.setBirthday(new java.util.Date(resultSet.getDate("birthday").getTime()));return user;}return null;} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{try {DBHelper.streamClose(connection, prepareStatement, resultSet);} catch (SQLException e) {// TODO Auto-generated catch blockSystem.out.println("关闭流出错了");}}return  null;}@Overridepublic User findUser(String name, String password) {// TODO Auto-generated method stubConnection connection = null;PreparedStatement prepareStatement = null;ResultSet resultSet =  null;String sql="select username,password,email,birthday from t_user where username=? and password=?";try {connection = DBHelper.getConnection();prepareStatement = connection.prepareStatement(sql);prepareStatement.setString(1, name);prepareStatement.setString(2, password);resultSet = prepareStatement.executeQuery();User user = new User();while(resultSet.next()){user.setUsername(resultSet.getString("username"));user.setPassword(resultSet.getString("password"));user.setEmail(resultSet.getString("email"));user.setBirthday(new java.util.Date(resultSet.getDate("birthday").getTime()));return user;}return null;} catch (SQLException e) {// TODO Auto-generated catch blocke.printStackTrace();}finally{try {DBHelper.streamClose(connection, prepareStatement, resultSet);} catch (SQLException e) {// TODO Auto-generated catch blockSystem.out.println("关闭流出错了");}}return  null;}}

top.wyxbs.exception包下的类:

/*** 用户已经存在异常类* @author chenjingbin**/
public class UserExistException extends Exception {/*** */private static final long serialVersionUID = 1L;public UserExistException() {}public UserExistException(String message) {super(message);}public UserExistException(Throwable cause) {super(cause);}public UserExistException(String message, Throwable cause) {super(message, cause);}
}

top.wyxbs.service包下的类：

import top.wyxbs.domain.User;
import top.wyxbs.exception.UserExistException;public interface BusinessService {/*** 完成用户信息注册* @param user 用户信息* @throws UserExistException 用户已经存在*/void regist(User user) throws UserExistException;/*** 完成用户登录* @param username 用户名* @param password 密码* @return 如果用户名或密码不正确，返回null*/User login(String username,String password);
}
//--------------------------------------------------
import top.wyxbs.dao.UserDao;
import top.wyxbs.dao.UserDaoImpl;
import top.wyxbs.domain.User;
import top.wyxbs.exception.UserExistException;public class BusinessServiceImpl implements BusinessService {private UserDao userDao = new UserDaoImpl();@Overridepublic void regist(User user) throws UserExistException {// TODO Auto-generated method stubUser findUserByName = userDao.findUserByName(user.getUsername());if(findUserByName!=null){throw new UserExistException(user.getUsername()+"已经存在");}userDao.save(user);}@Overridepublic User login(String username, String password) {// TODO Auto-generated method stubreturn userDao.findUser(username, password);}}
//------------------------------------------------------import java.util.HashMap;
import java.util.Map;import org.apache.commons.beanutils.locale.converters.DateLocaleConverter;
/*** 用户注册时临时产生的注册用户类* @author chenjingbin**/
public class UserRegistFormBean {private String username;private String password;private String repassword;private String email;private String birthday;//存放错误信息private Map<String , String > errors = new HashMap<String ,String >();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;}public Map<String, String> getErrors() {return errors;}/*** 验证信息，服务器端* @return*/public boolean validate(){//只要不满足要求的，就像errors中放消息//用户名必须输入，3~8位字母组成if(username==null||username.equals("")){errors.put("username", "请输入用户名");}else{if(!username.matches("[a-zA-Z]{3,8}")){errors.put("username", "用户名不符合要求");}}//密码必须输入，3~8位数字组成if(password == null || password.equals("")){errors.put("password", "请输入密码");}else{if (!password.matches("\\d{3,8}")) {errors.put("password", "密码不符合要求");}}//重复密码必须和密码一致if(repassword == null || repassword.equals("")){errors.put("repassword", "请输入密码");}else{if(!password.equals(repassword)){errors.put("repassword", "两次输入的密码不对");}}//邮箱必须输入，且要符合邮箱的格式if(email == null || email .equals("")){errors.put("email", "请输入邮箱");}else{if (!email.matches("\\b^['_a-z0-9-\\+]+(\\.['_a-z0-9-\\+]+)*@[a-z0-9-]+(\\.[a-z0-9-]+)*\\.([a-z]{2}|aero|arpa|asia|biz|com|coop|edu|gov|info|int|jobs|mil|mobi|museum|name|nato|net|org|pro|tel|travel|xxx)$\\b")) {errors.put("email", "邮箱格式不符合");}}if(birthday == null || birthday .equals("")){errors.put("birthday", "请输入生日");}else{try{new DateLocaleConverter().convert(birthday);}catch (Exception e) {errors.put("birthday", "请输出正确的日期");}}return errors.isEmpty();}
}

在写后端代码的时候写完一个小功能代码都需要去测试一下才行，于是有一个test包。

public class BusinessServiceImplTest {private BusinessService businessService = new BusinessServiceImpl();@Testpublic void registTest(){User user = new User();user.setUsername("abc");user.setPassword("456");user.setEmail("764024@qq.com");user.setBirthday(new Date());try {businessService.regist(user);} catch (UserExistException e) {// TODO Auto-generated catch blockSystem.out.println("已经存在");}}@Testpublic void loginTest(){User login = businessService.login("abc", "456");System.out.println(login);}
}
//-------------------------------------------------------
import java.util.Date;import org.junit.Test;import top.wyxbs.dao.UserDao;
import top.wyxbs.dao.UserDaoImpl;
import top.wyxbs.domain.User;/*** 测试userDaoImpl类* @author chenjingbin**/
public class UserDaoImplTest {@Testpublic void saveTest(){//测试保存用户是否成功User user = new User();user.setUsername("小黄");user.setPassword("123");user.setEmail("qewrer");user.setBirthday(new Date());UserDao userDao =new UserDaoImpl();userDao.save(user);}@Testpublic void findUserByNameTest(){UserDao userDao =new UserDaoImpl();User findUserByName = userDao.findUserByName("小黄");System.out.println(findUserByName.toString());}@Testpublic void findUserTest(){UserDao userDao =new UserDaoImpl();User findUserByName = userDao.findUser("小黄","123");System.out.println(findUserByName.toString());}
}

top.wyxbs.web.controller包下的类：

import java.io.IOException;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;import top.wyxbs.domain.User;
import top.wyxbs.service.BusinessService;
import top.wyxbs.service.BusinessServiceImpl;public class LoginServlet extends HttpServlet {private static final long serialVersionUID = 1L;private BusinessService s = new BusinessServiceImpl();protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubrequest.setCharacterEncoding("utf-8");response.setContentType("text/html;charset=utf-8");String username = request.getParameter("username");String password = request.getParameter("password");User login = s.login(username, password);if(login != null){request.getSession().setAttribute("user", login);response.getWriter().write("登录成功,2秒转向主页");response.setHeader("Refresh", "2;URL="+request.getContextPath());}else{response.getWriter().write("错误的用户名或密码,2秒转向登录页面");response.setHeader("Refresh", "2;URL="+request.getContextPath()+"/login.jsp");}}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubdoGet(request, response);}}
//---------------------------------------------------
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;/*** * @author chenjingbin**/
public class LogoutServlet extends HttpServlet {private static final long serialVersionUID = 1L;protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubrequest.setCharacterEncoding("UTF-8");response.setContentType("text/html;charset=UTF-8");PrintWriter out = response.getWriter();request.getSession().removeAttribute("user");out.write("注销成功");response.setHeader("Refresh", "2;URL="+request.getContextPath());}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {// TODO Auto-generated method stubdoGet(request, response);}}
//-----------------------------------------------------
import java.io.IOException;
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 top.wyxbs.domain.User;
import top.wyxbs.exception.UserExistException;
import top.wyxbs.service.BusinessService;
import top.wyxbs.service.BusinessServiceImpl;
import top.wyxbs.service.UserRegistFormBean;
import top.wyxbs.util.WebUtil;public class RegistServlet extends HttpServlet {private static final long serialVersionUID = 1L;private BusinessService s = new BusinessServiceImpl();protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {//首先是考虑编码问题request.setCharacterEncoding("utf-8");response.setContentType("text/html;charset=utf-8");//UserRegistFormBean fillBean = WebUtil.fillBean(request, UserRegistFormBean.class);//说明信息不符合if(!fillBean.validate()){request.setAttribute("formbean", fillBean);request.getRequestDispatcher("/regist.jsp").forward(request, response);return ;}User user = new User();try {//注册转换器ConvertUtils.register(new DateLocaleConverter(), Date.class);BeanUtils.copyProperties(user, fillBean);} catch (IllegalAccessException | InvocationTargetException e) {// TODO Auto-generated catch blocke.printStackTrace();}try {s.regist(user);response.setHeader("Refresh", "2:URL="+request.getContextPath()+"/index.jsp");response.getWriter().write("注册成功");} catch (UserExistException e) {// TODO Auto-generated catch block//回显数据fillBean.getErrors().put("username", "用户已经存在");request.setAttribute("formbean", fillBean);request.getRequestDispatcher("/regist.jsp").forward(request, response);}}protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {doGet(request, response);}}

还有一个文件那就是web.xml文件：

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns="http://java.sun.com/xml/ns/javaee" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd" version="2.5"><display-name></display-name><servlet><servlet-name>RegistServlet</servlet-name><servlet-class>top.wyxbs.web.controller.RegistServlet</servlet-class></servlet><servlet><servlet-name>LoginServlet</servlet-name><servlet-class>top.wyxbs.web.controller.LoginServlet</servlet-class></servlet><servlet><servlet-name>LogoutServlet</servlet-name><servlet-class>top.wyxbs.web.controller.LogoutServlet</servlet-class></servlet><servlet-mapping><servlet-name>RegistServlet</servlet-name><url-pattern>/servlet/RegistServlet</url-pattern></servlet-mapping><servlet-mapping><servlet-name>LoginServlet</servlet-name><url-pattern>/servlet/LoginServlet</url-pattern></servlet-mapping><servlet-mapping><servlet-name>LogoutServlet</servlet-name><url-pattern>/servlet/LogoutServlet</url-pattern></servlet-mapping><welcome-file-list><welcome-file>index.jsp</welcome-file></welcome-file-list>
</web-app>

最后运行图：
这里写图片描述

大概就完成了。数据库设计这个比较简单那我就没有给大家去展示了，但是也要去说一下规则吧，创建一个项目那在mysql中也要去创建一个新的数据库，然后创建一个新的用户并设置权限。具体sql语句大家自行去查。
总结一下：这里面没有使用到ajax去处理，如果页面使用jsp代码块的话只用jsp表达式去获取值，用El表达式会出现空值的问题。