新闻发布项目——Servlet类（doLoginServlet）

package bdqn.newsManageServlet.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 bdqn.newsManageServlet.Dao.UserDao;
import bdqn.newsManageServlet.Dao.Impl.UserDaoImpl;
import bdqn.newsManageServlet.entity.User;

public class doLoginServlet extends HttpServlet {

	/**
	 * 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 {

		response.setContentType("text/html;charset=utf-8");
		PrintWriter out = response.getWriter();
		request.setCharacterEncoding("utf-8");
		//登录
		//获取用户名和密码
		String uname = request.getParameter("uname");//用户名
		String upwd = request.getParameter("upwd");//密码
		UserDao udao = new UserDaoImpl();
		User user = udao.getLoginUser(uname);
		if (user == null) {
			out.print("<script>alert('用户名错误！');location.href='./index.jsp';</script>");
		}else{
		//!user.getUserPassword().equals(upwd)==false
			if(!user.getUserPassword().equals(upwd)){
				out.print("<script>alert('密码错误！');location.href='./index.jsp';</script>");
			}else{
				//登录成功！
				//保存用户信息
				HttpSession session=request.getSession();
				session.setAttribute("user", user);
				response.sendRedirect("index.jsp");
			}
		}
	}

	/**
	 * 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 {

		doGet(request, response);
	}

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

}