關於JSP的一點疑問小結

最後更新：2018-12-08 來源：互聯網

上載者：User

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希望誰能幫我看一看問題出在哪?謝謝!
register.html部分: 複製代碼代碼如下:<!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">

</head>
<body>
<br>
<form action="register.jsp" method = "Post" name = "frm">
使用者名稱:<input type = "text" name = "in_username"><br>
密碼:<input type = "password" name = "in_password"><br>
<input type = "submit" name = "submit" value = "提交">
</form>
</body>
</html>

register.jsp部分: 複製代碼代碼如下:<%@ 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">

</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: 複製代碼代碼如下: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;
}
}
}
}

本文章原先以中文撰寫並發佈於 aliyun.com，亦設英文版本，僅作資訊用途。本網站不對文章的準確性，完整性或可靠性或其任何翻譯作出任何明示或暗示的陳述或保證。如對該文章有任何疑慮或投訴，請傳送電郵至 info-contact@alibabacloud.com 並提供相關疑慮或投訴的詳細說明。職員會於 5 個工作天內與您聯絡，一經驗證之後，即會刪除該侵權內容。

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