loginservlet.java

留言管理系统,用JAVA JSP + MVC + DAO完成

/*
 * To change this template, choose Tools | Templates
 * and open the template in the editor.
 */
package com.shx.note.servlet;

import com.shx.note.factory.DAOFactory;
import com.shx.note.vo.Person;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import java.util.logging.Level;
import java.util.logging.Logger;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;

/**
 *
 * @author Administrator
 */
public class LoginServlet extends HttpServlet {

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

    /** 
     * Handles the HTTP <code>POST</code> method.
     * @param request servlet request
     * @param response servlet response
     * @throws ServletException if a servlet-specific error occurs
     * @throws IOException if an I/O error occurs
     */
    @Override
    protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        String path = "login.jsp";
        // 声明一个集合类，用于保存错误信息
        List errors = new ArrayList();
        //1、接收传递的参数
        int p_id = Integer.parseInt(request.getParameter("p_id"));
        String p_password = request.getParameter("p_password");
        // 2、进行数据合法性验证，包括是否为空，长度是否满足等
        // 要将接收到的内容设置给Person对象
        Person person = new Person();
        person.setP_id(p_id);
        person.setP_password(p_password);
        person.setErrors(errors);
        // 3、如果合法，则进行数据库验证
        if (person.invalidate()) {
            try {
                // 进行数据库验证
                if (DAOFactory.getPersonDAOInstance().login(person)) {
                    // 如果为真，则表示用户ID和密码合法
                    // 设置用户姓名到session范围之中
                    request.getSession().setAttribute("p_name", person.getP_name());
                    // 修改跳转路径
                    path = "login_success.jsp";
                } else {
                    // 登陆失败
                    // 设置错误信息
                    errors.add("错误的用户ID或密码！");
                }
            } catch (Exception ex) {
                Logger.getLogger(LoginServlet.class.getName()).log(Level.SEVERE, null, ex);
            }
        }
        // 将错误信息保存
        request.setAttribute("errors", errors);
        request.setAttribute("person", person);
        // 进行跳转
        request.getRequestDispatcher(path).forward(request, response);
    }
}