checkuser.java

MIS管理系统

package login;
import database.*;
import java.io.IOException;
import java.io.PrintWriter;
import java.util.ArrayList;
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 bean.*;
public class CheckUser extends HttpServlet {
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		doPost(request,response);//将doget请求放入dopost方法中处理.
	}
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		request.setCharacterEncoding("gb2312");//支持中文简体。
		String username=request.getParameter("username");//读JSP中"username"文本框中传送过来的数据.
		String password = request.getParameter("password");
		String vcode=request.getParameter("vcode");
		String vcode_real=(String)request.getSession().getAttribute("vcode");//读验证码
		HttpSession session = request.getSession();//创建session对象；
		if(username.equals(""))//验证用户名是否为空.
			{
			session.setAttribute("usernamenull","1");
			response.sendRedirect("/software/leftlogin.jsp");
			}
		else if (password.equals(""))//验证密码是否为空
			{
			session.setAttribute("passwordnull","1");
			response.sendRedirect("/software/leftlogin.jsp");
			}
		else if (vcode.equals(""))//验证验证码是否为空	
			{
			session.setAttribute("vcodenull","1");
			response.sendRedirect("/software/leftlogin.jsp");
			}
		else if(vcode.equals(vcode_real))//验证验证码是否正确
	    {	
		DB db = new DB();
		Users u = new Users();
		u.setUsername(username);
		u.setPassword(password);
		if(new DB().check(u))//验证用户名密码是否正确.
			{
			ArrayList infolist =db.searchUserInfo(username);
			session.setAttribute("log",infolist);
			response.sendRedirect("/software/main.jsp");	//登录成功		
			}
		else
			{
			session.setAttribute("logerr","1");
			response.sendRedirect("/software/leftlogin.jsp");//登录失败.
			}
	    }
	    else
	    {
	    	session.setAttribute("vcodeerr","1");
	    	response.sendRedirect("/software/leftlogin.jsp");
	    }
	}
}