Java组件javabean用户登录实例详解

-- Create table create table P_USER (  id  VARCHAR2(50) not null,  username VARCHAR2(20),  password VARCHAR2(20),  email VARCHAR2(50) ) tablespace USERS  pctfree 10  initrans 1  maxtrans 255  storage  (  initial 64  minextents 1  maxextents unlimited  ); -- Add comments to the table comment on table P_USER  is '用户表'; -- Add comments to the columns comment on column P_USER.id  is 'id'; comment on column P_USER.username  is '用户名'; comment on column P_USER.password  is '密码'; comment on column P_USER.email  is 'email'; 

package com.baosight.bean;  import java.sql.Connection; import java.sql.DriverManager; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Statement;  /**数据库操作类  * <p>Title:DBAcess </p>  * <p>Description:TODO </p>  * <p>Company: </p>  * @author yuan  * @date 2016-5-22 下午12:40:24*/ public class DBAcess {  private String driver = "oracle.jdbc.driver.OracleDriver";  private String url = "jdbc:oracle:" + "thin:@127.0.0.1:1521:orcl";  private String username = "scott";  private String password = "tiger";  private Connection conn;  private Statement stm;  private ResultSet rs;  //创建连接  public boolean createConn() {   boolean b = false;   try {    Class.forName(driver);// 加载Oracle驱动程序    conn = DriverManager.getConnection(url, username, password);    b = true;   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }// 获取连接   catch (ClassNotFoundException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }   return b;  }  //修改  public boolean update(String sql){   boolean b = false;   try {    stm = conn.createStatement();    stm.execute(sql);    b = true;   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }   return b;  }  //查询  public void query(String sql){   try {    stm = conn.createStatement();    rs = stm.executeQuery(sql);   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }  }  //判断有无数据  public boolean next(){   boolean b = false;   try {    if(rs.next()){     b = true;    }   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }   return b;  }  //获取表字段值  public String getValue(String field) {   String value = null;   try {    if (rs != null) {     value = rs.getString(field);    }   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }   return value;  }  //关闭连接  public void closeConn() {   try {    if (conn != null) {     conn.close();    }   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }  }  //关闭statement  public void closeStm() {   try {    if (stm != null) {     stm.close();    }   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }  }  //关闭ResultSet  public void closeRs() {   try {    if (rs != null) {     rs.close();    }   } catch (SQLException e) {    // TODO Auto-generated catch block    e.printStackTrace();   }  }  public String getDriver() {   return driver;  }  public void setDriver(String driver) {   this.driver = driver;  }  public String getUrl() {   return url;  }  public void setUrl(String url) {   this.url = url;  }  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 Statement getStm() {   return stm;  }  public void setStm(Statement stm) {   this.stm = stm;  }  public ResultSet getRs() {   return rs;  }  public void setRs(ResultSet rs) {   this.rs = rs;  }  public void setConn(Connection conn) {   this.conn = conn;  }  public Connection getConn() {   return conn;  } } 

package com.baosight.bean;  import com.baosight.util.GenerateUUID;  /**  * <p>Title:UserBean </p>  * <p>Description:TODO </p>  * <p>Company: </p>  * @author yuan  * @date 2016-5-22 下午1:05:00*/ public class UserBean {  //登录验证  public boolean valid(String username,String password){   boolean isValid = false;   DBAcess db = new DBAcess();   if(db.createConn()){    String sql = "select * from p_user where username='"+username+"' and password='"+password+"'";    db.query(sql);    if(db.next()){     isValid = true;    }    db.closeRs();    db.closeStm();    db.closeConn();   }   return isValid;  }  //注册验证  public boolean isExist(String username){   boolean isValid = false;   DBAcess db = new DBAcess();   if(db.createConn()){    String sql = "select * from p_user where username='"+username+"'";    db.query(sql);    if(db.next()){     isValid = true;    }    db.closeRs();    db.closeStm();    db.closeConn();   }   return isValid;  }  //注册用户  public boolean add(String username,String password,String email){   boolean isValid = false;   DBAcess db = new DBAcess();   if(db.createConn()){    String sql = "insert into p_user(id,username,password,email) values('"+GenerateUUID.next()+"','"+username+"','"+password+"','"+email+"')";    isValid = db.update(sql);    db.closeStm();    db.closeConn();   }   return isValid;  } } 

package com.baosight.util;  import java.util.Date;  /**  * <p>Title:GenerateUUID </p>  * <p>Description:TODO </p>  * <p>Company: </p>  * @author yuan  * @date 2016-5-22 下午1:31:46*/ public class GenerateUUID {   private static Date date = new Date(); // private static StringBuilder buf = new StringBuilder();   private static int seq = 0;   private static final int ROTATION = 99999;   public static synchronized long next(){   if (seq > ROTATION) seq = 0; //  buf.delete(0, buf.length());   date.setTime(System.currentTimeMillis());   String str = String.format("%1$tY%1$tm%1$td%1$tk%1$tM%1$tS%2$05d", date, seq++);   return Long.parseLong(str);  }   public static void main(String[] args) {    for(int i=0;i<100;i++){     System.out.println(next());    }  } } 

<%@ 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>登录页面</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="login_action.jsp" method="post">   <table>    <tr>     <td colspan="2">登录窗口</td>    </tr>    <tr>     <td>用户名：</td>     <td><input type="text" name="username" />     </td>    </tr>    <tr>     <td>密码：</td>     <td><input type="text" name="password" />     </td>    </tr>    <tr>     <td colspan="2"><input type="submit" value="登录" /> <a href="register.jsp">注册</a>     </td>    </tr>   </table>  </form> </body> </html> 

<%@ page language="java" import="java.util.*" pageEncoding="utf-8"%> <%@ page import="java.sql.*" %> <%@ page import="com.baosight.bean.*" %> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %>   <%  String username = request.getParameter("username");  String password = request.getParameter("password");  if(username==null||"".equals(username.trim())||password==null||"".equals(password.trim())){   //out.write("用户名或密码不能为空！");   System.out.println("用户名或密码不能为空！");   response.sendRedirect("login.jsp");   return;   //request.getRequestDispatcher("login.jsp").forward(request, response);  }  UserBean userBean = new UserBean();  boolean isValid = userBean.valid(username,password);  if(isValid){   System.out.println("登录成功！");   session.setAttribute("username", username);   response.sendRedirect("welcome.jsp");   return;  }else{   System.out.println("用户名或密码错误，登录失败！");   response.sendRedirect("login.jsp");   return;  }  %> 

<%@ 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>My JSP 'welcom.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>  <table>   <tr>    <td><img src="images/logo4.png" />    </td>    <td><img src="images/logo2.png" height="90" />    </td>   </tr>   <tr>    <td colspan="2"><hr />    </td>   </tr>   <tr>    <td>     <table>      <tr>       <td><a>Main</a>       </td>      </tr>      <tr>       <td><a>Menu1</a>       </td>      </tr>      <tr>       <td><a>Menu2</a>       </td>      </tr>      <tr>       <td><a>Menu3</a>       </td>      </tr>      <tr>       <td><a>Menu4</a>       </td>      </tr>      <tr>       <td><a>Menu5</a>       </td>      </tr>      <tr>       <td><a>Menu6</a>       </td>      </tr>      <tr>       <td><a>Menu7</a>       </td>      </tr>      <tr>       <td><a>Menu8</a>       </td>      </tr>     </table></td>    <td>     <form action="loginout.jsp" method="post">      <table>       <tr>        <td colspan="2">登录成功!</td>       </tr>       <tr>        <td>欢迎你，</td>        <td>${username }</td>       </tr>       <tr>        <td colspan="2"><input type="submit" value="退出" /></td>       </tr>      </table>     </form></td>   </tr>  </table> </body> </html> 

<%@ 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>My JSP 'loginout.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>  <%  session.removeAttribute("username");  response.sendRedirect("login.jsp");  %>  </body> </html> 

<%@ 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>注册页面</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="register_action.jsp" method="post">   <table>    <tr>     <td colspan="2">注册窗口</td>    </tr>    <tr>     <td>用户名：</td>     <td><input type="text" name="username" /></td>    </tr>    <tr>     <td>密码：</td>     <td><input type="text" name="password1" /></td>    </tr>    <tr>     <td>确认密码：</td>     <td><input type="text" name="password2" /></td>    </tr>    <tr>     <td>email：</td>     <td><input type="text" name="email" /></td>    </tr>    <tr>     <td colspan="2"><input type="submit" value="注册" /> <a href="login.jsp">返回</a></td>    </tr>   </table>  </form> </body> </html> 

<%@ page language="java" import="java.util.*" pageEncoding="UTF-8"%> <%@ page import="java.sql.*" %> <%@ page import="com.baosight.bean.*" %> <% String path = request.getContextPath(); String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/"; %>    <%  String username = request.getParameter("username");  String password1 = request.getParameter("password1");  String password2 = request.getParameter("password2");  String email = request.getParameter("email");  if(username==null||"".equals(username.trim())||password1==null||"".equals(password1.trim())||password2==null||"".equals(password2.trim())||!password1.equals(password2)){   //out.write("用户名或密码不能为空！");   System.out.println("用户名或密码不能为空！");   response.sendRedirect("register.jsp");   return;   //request.getRequestDispatcher("login.jsp").forward(request, response);  }  UserBean userBean = new UserBean();  boolean isExit = userBean.isExist(username);  if(!isExit){   userBean.add(username, password1, email);   System.out.println("注册成功，请登录！");   response.sendRedirect("login.jsp");   return;  }else{   System.out.println("用户名已存在！");   response.sendRedirect("register.jsp");   return;  }  %>