loginservlet.java

这个是j2eejava web 编程精要十五讲的全部源码。对学习java web编程的人来说是很能得的资料

package login;

//* 控制组件 */

import javax.servlet.*;
import javax.servlet.http.*;
import java.io.*;
import java.util.*;

public class LoginServlet extends HttpServlet {
  private static final String CONTENT_TYPE = "text/html; charset=GB2312";
  //初始化Servlet
  public void init() throws ServletException {
  }
  //处理 HTTP POST请求
  public void doPost(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
//从请求中取出用户名和密码的值
    String username = request.getParameter("username");
    String password = request.getParameter("password");

//生成一个ArrayList对象，并把用户名和密码的值存入该对象中
      ArrayList arr = new ArrayList();
       arr.add(username);
       arr.add(password);

    //生成一个Session 对象
       HttpSession session = request.getSession(true);
       session.removeAttribute("username");
       session.setAttribute("username",username);

      //调用模型组件loginHandler，检查该用户是否已注册
       LoginHandler login = new LoginHandler();
       boolean mark = login.checkLogin(arr);

       //如果已注册，进入主页面
       if(mark) response.sendRedirect("main.jsp");
       //如果未注册，进入注册页面
       else  response.sendRedirect("register.jsp");
  }
   //处理 HTTP GET请求
  public void doGet(HttpServletRequest request, HttpServletResponse response)
      throws ServletException, IOException {
     doPost(request,response);
      }
  //销毁Servlet
  public void destroy() {
  }
}