7017f850e286001d18b3f3489ec5d0da

一个相对比较简单的留言簿！功能还比较齐全！

package com.pure35.servlet;

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;

import com.pure35.database.UserDao;

//该servlet控制器(Login)是由login.jsp页面中登陆按扭的action（）方法调用其映射
//通过该servlet控制器(Login)调用数据操作类UserDao中的login方法验证用户的合法性，然后进行页面的跳转 

public class Login extends HttpServlet {
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

	
		UserDao userDao=new UserDao();
		String sql=null;
		boolean isLogin=false;
		String userName=request.getParameter("userName");
		String password=request.getParameter("password");
		
		sql="select count(*) as mycount from user where username='"+userName+"'  and password='"+password+"' ";
		//可以通过这语句System.out.println(sql);去检查数据库的操作ＳＱＬ语句！
		isLogin=userDao.login(sql);
		if(isLogin)
		{	
			request.getRequestDispatcher("welcome.jsp").forward(request, response);		
		}
		else{
			
			request.getRequestDispatcher("login.jsp").forward(request, response);
		}
		
	}

}