checkloginservlet.java

oa办公系统

package cn.jx.ecjtu.oa.servlets.users;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Date;
import java.util.List;

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 javax.servlet.ServletContext;
import cn.jx.ecjtu.oa.common.Constant;
import cn.jx.ecjtu.oa.ps.pojo.LoginUser;
import cn.jx.ecjtu.oa.ps.pojo.Role;
import cn.jx.ecjtu.oa.services.OnlineList;
import cn.jx.ecjtu.oa.services.Result;
import cn.jx.ecjtu.oa.services.ServiceFactory;
import cn.jx.ecjtu.oa.services.SysUserService;
import cn.jx.ecjtu.oa.services.UserInSession;

public class CheckLoginServlet 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 {
		this.doPost(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 {
		//SysUserService service 提供登录用户验证的方法checkUser(String login_name, String password);    	
		HttpSession session = request.getSession();
		String loginName = request.getParameter("loginName");
		String password = request.getParameter("password");

		//对登陆的用户进行查找
		LoginUser loginUser = null;
	
		loginUser = service.checkUser(loginName, password);
    
		if (null != loginUser) //成功登陆
		{  
			int role_id=loginUser.getRoleId();
			loginUser.setSessionID(session.getId()); //设置成功登陆的session id
			Role role=service.findRoleById(role_id);
			UserInSession user_in_session=new UserInSession(loginUser.getId(),loginUser.getRealName(),role,loginUser.getDeptID());
			
			//添加到在线用户列表
			ServletContext application =this.getServletContext();
			
			if (null == application.getAttribute(Constant.ONLINELIST_IN_APPLICATION)) //服务器中还没有在线人员列表，则创建这个列表
			{
				OnlineList list = new OnlineList();
				application.setAttribute(Constant.ONLINELIST_IN_APPLICATION,list);
			}
			
			//这时application中肯定已经有在线人员列表	
			
			OnlineList list = (OnlineList) application.getAttribute(Constant.ONLINELIST_IN_APPLICATION);
			
			if (list.isOnline(loginUser)) //如果该用户已经登陆了，则返回一个已经登陆错误到error.jsp
			{
			    request.setAttribute("message","<div align='center'>出错原因可能如下:<br>1.该用户已经登陆了,同一个帐号不能同时多处登陆,请选择另外一个帐号登陆.<br>2.未安全退出,请等待一会后再登陆.<p><a href='index.jsp'>重新登陆</a></div>");
				request.getRequestDispatcher("error.jsp").forward(request,response);
				//list.getUserById(loginUser.getId()).setSessionID(loginUser.getSessionID());//更新已经有的session id为当前session id;
				
			} else
			{
				list.addOnlineUser(loginUser);
				application.setAttribute(Constant.ONLINELIST_IN_APPLICATION,list); //更新到Application的ONLINE_LIST
				session.setAttribute(Constant.USER_IN_SESSION,user_in_session);    //把登陆信息记录到Session中提供给其他应用使用
				response.sendRedirect("main.jsp");
			}

		} 
		else //登陆失败，返回一个登陆失败错误到error.jsp,该用户不存在
		{
			request.setAttribute("message","登陆失败,该用户不存在或密码不正确!");
			request.getRequestDispatcher("error.jsp").forward(request,response);
		}

	}

	/**
	 * Initialization of the servlet. <br>
	 *
	 * @throws ServletException if an error occure
	 */
	private SysUserService service;//使用到的SysUserService的对象

	public void init() throws ServletException {
		service = (SysUserService) ServiceFactory.getService(SysUserService.class);
	}

}