loginservlet.java

用eclipse3.3和myeclipse6.o开发的简单登录系统用到的数据库为DB2 8.2

package cn.itcareers.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 cn.itcareers.exception.UserIllegalException;
import cn.itcareers.exception.UserNotFoundException;
import cn.itcareers.model.User;
import cn.itcareers.service.UserService;

public class LoginServlet extends HttpServlet {

	/**
	 * Constructor of the object.
	 */
	public LoginServlet() {
		super();
	}

	/**
	 * Destruction of the servlet. <br>
	 */
	public void destroy() {
		super.destroy(); // Just puts "destroy" string in log
		// Put your code here
	}

	/**
	 * The doGet method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to get.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doGet(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {
		request.setCharacterEncoding("GB18030");
		String username = request.getParameter("username");
		String userpwd = request.getParameter("userpwd");
		String path = "list.jsp";
		UserService us = new UserService();
		try {
			User user = us.getUserByNameAndPassword(username, userpwd);  
			request.getSession().setAttribute("user", user);
		} catch (UserNotFoundException e) {
			path = "login.jsp";
			request.setAttribute("failMsg1", "用户名不存在！");
		} catch (UserIllegalException e) {
			path = "login.jsp";
			request.setAttribute("failMsg2", "用户名与密码不匹配！");
		}
		request.getRequestDispatcher(path).forward(request, response);
	}

	/**
	 * The doPost method of the servlet. <br>
	 *
	 * This method is called when a form has its tag value method equals to post.
	 * 
	 * @param request the request send by the client to the server
	 * @param response the response send by the server to the client
	 * @throws ServletException if an error occurred
	 * @throws IOException if an error occurred
	 */
	public void doPost(HttpServletRequest request, HttpServletResponse response)
			throws ServletException, IOException {

		this.doGet(request,response);
	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occurs
	 */
	public void init() throws ServletException {
		// Put your code here
	}

}