login.java

java 数据库编程实例 经过反复调试 保证可以运行 是学习java网络编程的绝佳资料

package chatroom;
import java.sql.*;
import java.util.*;
import javax.servlet.*;
import javax.servlet.http.*;
import javax.servlet.jsp.*;
import javax.servlet.jsp.tagext.*;
import java.io.*;

/**
 * Title:        JSP聊天室
 * Description:  Java语言演示程序：JSP聊天室，用于北京师范大学计算机系Java课程教学示范。
 * Copyright:    Copyright (c) 2002
 * Company:      北京师范大学计算中心
 * @author 张庆利
 * @version 1.0
 */

public class Login extends HttpServlet {
    public void doGet(HttpServletRequest request,HttpServletResponse response)
        throws IOException, ServletException{
     String Name=request.getParameter("name");
     String Password=request.getParameter("password");
     HttpSession session=request.getSession(true);
     int i;
     char[] Temp=Password.toCharArray();
     for (i=0;i<Password.length();i++) Temp[i]=(char)(Temp[i]+i+1);
     Password=Password.copyValueOf(Temp);
     DBconn DBconn1= new DBconn();
     ResultSet RS = DBconn1.executeQuery ("select * from usertable where user_id='"+Name+"' and user_password='"+Password+"'");
     try{
     if (RS.next()){
         oneUser thisUser=new oneUser();
         String user_id = RS.getString("user_id");
         String user_password = RS.getString("user_password");
         String position=new String("0");
         java.util.Date dateTimenow=new java.util.Date();
         long longDateTimeNow=(long)dateTimenow.getTime();
         thisUser.setOneUser(user_id,user_password,longDateTimeNow,position);
         session.putValue("thisUser",thisUser);
         ServletContext application=getServletContext();
         userList theUserList;
         if (application.getAttribute("userlist")==null) theUserList=new userList();
         else theUserList=(userList)application.getAttribute("userlist");
         theUserList.addUserList(user_id,user_password,longDateTimeNow,position);
         application.setAttribute("userlist",theUserList);
         getServletConfig().getServletContext().getRequestDispatcher("/mytest/jsp/index.jsp").forward(request,response);
        }
     else
        getServletConfig().getServletContext().getRequestDispatcher("/mytest/jsp/login.jsp").forward(request,response);
       RS.close();
	}
     catch(SQLException ex){
        System.err.println("操作数据库错误："+ex.getMessage());
     }
  }
  public void doPost(HttpServletRequest request,HttpServletResponse response)
        throws IOException, ServletException {
        doGet(request, response);
  }
}