checkservlet.java

jsp+servlet经典的登录注册

package 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 javax.servlet.http.HttpSession;

import dao.RegisterDAO;

public class CheckServlet extends HttpServlet {

	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		request.setCharacterEncoding("gbk");
		response.setContentType("text/html;charset=gbk");
		PrintWriter out = response.getWriter();
		HttpSession session = request.getSession(true);
		String userName = request.getParameter("userName");
		String passWord = request.getParameter("passWord");
		RegisterDAO registerDAO = new RegisterDAO();
		String sql = "select count(*) from register where userName=? and passWord=?";
		int n = registerDAO.CheckPesson(sql, userName, passWord);
		//放置在什么地方
		session.setAttribute("userName", userName);
		if(n > 0){
			
			response.sendRedirect("/login/servlet/LoginCheck");
		} else {
			out.write("<script type='text/javascript'>alert('用户名或密码错误,登录失败,请重新登录!');</script>");
			request.getRequestDispatcher("/login.jsp").include(request, response);
		}
		out.flush();
		out.close();
	}

	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		this.doGet(request, response);
	}

}