关于JSP的一点疑问小结

  希望谁能帮我看一看问题出在哪?谢谢!

  register.html部分:

  

复制代码 代码如下:

  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

  <html>

  <head>

  <title>register.html</title>

  <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">

  <meta http-equiv="description" content="this is my page">

  <meta http-equiv="content-type" content="text/html; charset=UTF-8">

  <!--<link rel="stylesheet" type="text/css" href="./styles.css">-->

  </head>

  <body>

  <br>

  <form action="register.jsp" method = "Post" name = "frm">

  用户名:<input type = "text" name = "in_username"><br>

  密码:<input type = "password" name = "in_password"><br>

  <input type = "submit" name = "submit" value = "提交">

  </form>

  </body>

  </html>

  register.jsp部分:

  

复制代码 代码如下:

  <%@ page language="java" import = java.util.* pageEncoding="ISO-8859-1"%>

  <%

  String path = request.getContextPath();

  String basePath = request.getScheme()+"://"+request.getServerName()+":"+request.getServerPort()+path+"/";

  %>

  <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">

  <html>

  <head>

  <base href="<%=basePath%>">

  <title>My JSP 'register.jsp' starting page</title>

  <meta http-equiv="pragma" content="no-cache">

  <meta http-equiv="cache-control" content="no-cache">

  <meta http-equiv="expires" content="0">

  <meta http-equiv="keywords" content="keyword1,keyword2,keyword3">

  <meta http-equiv="description" content="This is my page">

  <meta http-equiv = "content-type" content = "text/html;charset = gb2312">

  <!--

  <link rel="stylesheet" type="text/css" href="styles.css">

  -->

  </head>

  <body>

  <br>

  <%! boolean isnotlogin = false;%>

  <%

  String username = request.getParameter("username");

  String password = request.getParameter("password");

  if(username == null || password == null)

  {

  response.sendRedirect("error.jsp");

  return;

  }

  %>

  <jsp:useBean id="person" scope = "page" class = "mypack.register">

  <jsp:setProperty name = "person" property = "username" param = "username"/>

  <jsp:setProperty name = "person" property = "pwd" param = "password"/>

  </jsp:useBean>

  <%

  isnotlogin = person.judge();

  if(!isnotlogin)

  {

  response.sendRedirect("error.jsp");

  return;

  }

  else

  {

  session.setAttribute("username", request.getParameter("username"));

  %>

  <jsp:forward page = "sbmt">

  <jsp:param name = "username" value = "<%=username%>"/>

  </jsp:forward>

  <%

  }

  %>

  </body>

  </html>

  register.java(JavaBean)部分:

  

复制代码 代码如下:

  package mypack;

  public class register {

  private String username = "";

  private String pwd = "";

  public void setUserName(String nm)

  {

  this.username = nm;

  }

  public String getUserName()

  {

  return this.username;

  }

  public void setPwd(String pd)

  {

  this.pwd = pd;

  }

  public String getPwd()

  {

  return this.pwd;

  }

  public boolean judge()

  {

  boolean temp = false;

  if(username.equals("teacher") && pwd.equals("teacher"))

  {

  temp = true;

  }

  return temp;

  }

  }

  sbmt.java(Servlet)部分:

  package mypack;

  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;

  public class sbmt extends HttpServlet {

  private static final long serialVersionUID = 1L;

  public sbmt() {

  super();

  }

  public void destroy() {

  super.destroy();

  }

  public void doGet(HttpServletRequest request, HttpServletResponse response)

  throws ServletException, IOException {

  response.setContentType("text/html");

  PrintWriter out = response.getWriter();

  out

  .println("<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.01 Transitional//EN\">");

  out.println("<HTML>");

  out.println(" <HEAD><TITLE>A Servlet</TITLE></HEAD>");

  out.println(" <BODY>");

  out.print(" This is ");

  out.print(this.getClass());

  out.println(", using the GET method");

  out.println(" </BODY>");

  out.println("</HTML>");

  out.flush();

  out.close();

  }

  public void doPost(HttpServletRequest request, HttpServletResponse response)

  throws ServletException, IOException {

  HttpSession session = request.getSession(false);

  if(session == null)

  {

  response.sendRedirect("error.jsp");

  return;

  }

  String usernameone = (String)session.getAttribute("username");

  String usernametwo = request.getParameter("username");

  if(!usernameone.equals(usernametwo))

  {

  response.sendRedirect("error.jsp");

  return;

  }

  response.setContentType("text/html;charset = GBK");

  request.setAttribute("username", usernametwo);

  if(usernametwo.equals("teacher"))

  {

  response.sendRedirect("teacher.jsp");

  return;

  }

  else

  {

  response.sendRedirect("error.jsp");

  return;

  }

  }

  }

  }