＜body＞代数和为负整数，其和值为：${add.x}+${add.y}=${add.sum}＜/body＞

    package com.model.user;
    public class EndUser{
      private Integer userId;
      private String userName;
      private String userPassword;
      private String userRealName;
      //这里省略了所有属性的setter/getter方法
    }

    package com.db_util;
    import java.sql.*;
    public class DBConnection {
      private static String driverName="com.mysql.jdbc.Driver"; //MySQL数据库驱动程序
      private static String userName="root";  //数据库用户名
      private static String userPwd="123456"; //数据库用户密码
      private static String dbName="struts2";  数据库名称
      public static Connection getDBConnection(){ //获取数据库连接对象的方法
        String url1="jdbc:mysql://localhost/"+dbName;
        String url2="? user="+userName+"&password="+userPwd;
        String url3="&useUnicode=true&characterEncoding=utf-8";
        String url=url1+url2+url3;    //形成数据库连接字
        Connection con=null;
        try {
          Class.forName(driverName);   //加载驱动
          con=DriverManager.getConnection(url); //获取数据库连接对象
        } catch (Exception e) {e.printStackTrace(); }
        return con;
      }
      //关闭数据库连接的各资源对象
      public static void closeDB(Connection con, PreparedStatement pstm, ResultSet rs){
        if(rs! =null) try {rs.close(); } catch (SQLException e) {e.printStackTrace(); }
        if(pstm! =null) try {pstm.close(); } catch (SQLException e) {e.printStackTrace(); }
        if(con! =null) try {con.close(); } catch (SQLException e) {e.printStackTrace(); }
      }
    }

    package com.dao.user;
    //省略了import导入包；
    public class UserDao {
      public int save(EndUser user) { //向数据库中插入一个用户的方法
        Connection con=null;
        PreparedStatement pstmt=null;
        ResultSet rs=null;
        con=DBConnection.getDBConnection();
        int row=0;
        String sql="insert into user(userName, userPassword, userRealName) values(? , ? , ? )";
        try {
          pstmt=con.prepareStatement(sql);
          pstmt.setString(1, user.getUserName());
          pstmt.setString(2, user.getUserPassword());
          pstmt.setString(3, user.getUserRealName());
          row=pstmt.executeUpdate();
        } catch (Exception e) {e.printStackTrace(); }
        finally{DBConnection.closeDB(con, pstmt, rs); }
        return row;
      }
      public EndUser find(EndUser user) { //从数据库中查找一个用户，用于验证是否注册
        Connection con=null;
        PreparedStatement pstmt=null;
        ResultSet rs=null;
        con=DBConnection.getDBConnection();
        EndUser user2=null;
        String sql="select * from user where userName=? and userPassword=? ";
        try {
          pstmt=con.prepareStatement(sql);
          pstmt.setString(1, user.getUserName());
          pstmt.setString(2, user.getUserPassword());
          rs=pstmt.executeQuery();
          if(rs.next()){
            user2=new EndUser();
            user2.setUserId(rs.getInt("id"));
            user2.setUserName(rs.getString("userName"));
            user2.setUserPassword(rs.getString("userPassword"));
            user2.setUserRealName(rs.getString("userRealName"));
              }
          } catch (Exception e) {e.printStackTrace(); }
        finally{DBConnection.closeDB(con, pstmt, rs); }
        return user2;
      }
    }

    package com.action.user;
    //省略了import导入包；
    public class UserAction {
      private EndUser user;
      private UserDao userDao = new UserDao();
      public String userLogin() throws Exception {//用户登录Action方法
        String forward = null;
        EndUser user2 = userDao.find(user);
        if(user2! =null){forward="success"; }else{ forward="failure"; }
        return forward;
      }
      public String userRegister() throws Exception {//用户注册Action方法
        String forward="error";   //数据库存数据时出错标记值
        int flag = 0;
        EndUser user2=(userDao.find(user));
        if (user2! =null){forward = "error_user"; //用户名已被占用标记标记值
        } else {
          flag = userDao.save(user);
          if (flag = = 1) {forward = "success"; //成功注册标记值}
        }
        return forward;
      }
      //这里省略了属性user的set/get方法，对于属性UserDao userDao，不需要set/get方法
    }

    ＜struts＞
        ＜include file="struts-user.xml" /＞
    ＜/struts＞

    ＜body＞
      ＜form method="post" action="/struts2user/user/logincheck"＞
      ＜table＞
        ＜tr＞＜th colspan="2"＞用户登录＜/th＞＜/tr＞
        ＜tr＞＜td align="right"＞用户名：＜/td＞ ＜td＞＜input name="user.userName" /＞＜/td＞ ＜/tr＞
        ＜tr＞＜td align="right"＞密码：＜/td＞
          ＜td＞＜input type="password" name="user.userPassword" /＞＜/td＞ ＜/tr＞
        ＜tr＞＜td align="left"＞＜input type="submit" value="登录" /＞＜/td＞
          ＜td＞未注册者，请先注册，单击＜a href="/struts2user/user/register.jsp"＞注册＜/a＞＜/td＞
        ＜/tr＞
      ＜/table＞
      ＜/form＞
    ＜/body＞

    ＜body＞
      欢迎你，${user.userRealName}，你登入成功！! ＜br＞
      进入主页面，请点击＜a href="/struts2user/index.jsp"＞主页面＜/a＞
    ＜/body＞

    ＜body＞
      ＜h2 align="center"＞
        ＜font color="red"＞对不起，你填写的账号和密码不正确！请＜/font＞
          ＜a href="/struts2user/user/login.jsp"＞重新登录＜/a＞
      ＜/h2＞
    ＜/body＞

    ＜head＞＜title＞注册页面＜/title＞
    ＜script type="text/javascript"＞
      function isValidate(form) {
        var username=document.getElementById("username").value;
        var userpass=document.getElementById("userpassword").value;
        var userpass1=document.getElementById("userpass1").value;
        if (userpass ! = userpass1) {
          alert("两次密码输入不一致，请重新输入！");
          return false;
        }else if (userpass.length＜=0 ||username.length＜=0 ) {
          alert("用户名以及密码不能为空，请重新输入！");
          return false; }
        else{return true; }
      }
    ＜/script＞＜/head＞
    ＜body＞
      ＜h3 align="left"＞欢迎注册我们的系统，请认真填写您的信息＜/h3＞
      ＜form name="register" action="/struts2user/user/register"
                  method="post"  onsubmit="return isValidate()"＞
        ＜table＞
          ＜tr＞＜td align="right"＞账户名：＜/td＞
            ＜td＞＜input name="user.userName" id="username"＞＜/td＞＜/tr＞
          ＜tr＞＜td align="right"＞为您的账户设置密码：＜/td＞
            ＜td＞＜input type="password"
                      name="user.userPassword" id="userpassword"＞＜/td＞＜/tr＞
          ＜tr＞＜td align="right"＞再次确认您的密码：＜/td＞
            ＜td＞＜input type="password" name="userpass1" id="userpass1"＞＜/td＞＜/tr＞
          ＜tr＞＜td align="right"＞真实姓名：＜/td＞
            ＜td＞＜input  name="user.userRealName"id="userrealname"＞＜/td＞＜/tr＞
          ＜tr＞＜td align="right"＞＜input type="submit" value="提交"＞＜/td＞
            ＜td colspan="2"＞＜input type="reset" value="重新填写"＞＜/td＞＜/tr＞
        ＜/table＞
      ＜/form＞
    ＜/body＞