login_confirm.java

一个真实的网络选课系统,由实际需求得到的,本人实际开发出来,运用JSP+TOMCAT

package servlet;

import java.io.IOException;
import java.sql.ResultSet;

import javax.servlet.RequestDispatcher;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.servlet.http.HttpSession;

import com.JDBConnection;
import log.*;

public class Login_confirm extends HttpServlet {

public void doPost(HttpServletRequest req, HttpServletResponse res)
throws ServletException, IOException {	
        
   String message=null; 
   String id=null;
   id=req.getParameter("id");
   HttpSession session=req.getSession(true);
   
   String password=null;
   password= req.getParameter("password");
 
   
   String temp =getPassword(req,res,id);
   if( password.equals(temp))
   {
	   System.out.println("学生登陆成功");
	  // String mess=id+"登陆成功";
	   //CreateLogs.createLog(mess, "Login_confirm.java");
	   session.setAttribute("id",String.valueOf(id));
	   goo(req,res);
   }
   else {
	   System.out.println("学生登陆失败");
	   message="用户名或密码有误！";
	   doError(req,res,message)	;
 	}
 	} 
  
public void goo(HttpServletRequest req, HttpServletResponse res)
throws ServletException,IOException
	{
	res.sendRedirect("http://222.192.23.25:8088/select/user/index.jsp");
	}
	

  
     
public String getPassword(HttpServletRequest req, HttpServletResponse res,
                        String id)
                        throws ServletException, IOException {
	   JDBConnection db= new JDBConnection(); 
	   String name="";
	   String pw="";                     	                     	
	   String sql="select pwd ,name from userInfo where stdno='"+id+"'";
	   try{
	   ResultSet rs=db.executeQuery(sql); 	
	   if(rs.next() ){
		   				pw= rs.getString("pwd").trim();
		   				name=rs.getString("name");
		   				HttpSession session=req.getSession(true);
		   			    session.setAttribute("name",name);
	   				 }
	   db.closeConnection();
	   	} 
	   	catch(Exception e)
	   		{
	   		CreateLogs.createLog(e, "Login_confirm.java");
	   		System.out.print(e.toString());
	   		}   	    
	   		return pw; 
    }
     
     	
      
public void doError(HttpServletRequest req,
                      HttpServletResponse res,
                      String str)
                      throws ServletException, IOException {

				    req.setAttribute("problem", str);
				    RequestDispatcher rd = getServletContext().getRequestDispatcher("/login.jsp");
				    rd.forward(req, res);
				    
				  }
}