using httpsession for session management

Question

facing problem to manage session in servlet program. this is my servlet code.

//`SessionUsingHttpSession .java

package suprio.servlets.examples;

import java.io.IOException;

import javax.servlet.RequestDispatcher;
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 org.apache.catalina.Session;

/**
 * Servlet implementation class SessionUsingHttpSession
 */
public class SessionUsingHttpSession extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
 * @see HttpServlet#HttpServlet()
 */
public SessionUsingHttpSession() {
    super();
    // TODO Auto-generated constructor stub
}

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response)   throws ServletException, IOException {
    // TODO Auto-generated method stub
    response.setContentType("<html/text");
    String name = request.getParameter("txtName4");
    String pass = request.getParameter("txtPassword4");
    if(pass.equals("12345"))
    {
        HttpSession session = request.getSession();
        session.setAttribute("user", name);
        //response.sendRedirect("SessionUsingHttpSessionRedirected");
        RequestDispatcher rd =       request.getRequestDispatcher("SessionUsingHttpSessionRedirected");
    }
}

}

and the following code is the redirected from SessionUsingHttpSession.java

//SessionUsingHttpSessionRedirected.java
package suprio.servlets.examples;

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;

/**
 * Servlet implementation class SessionUsingHttpSessionRedirected
*/
public class SessionUsingHttpSessionRedirected extends HttpServlet {
private static final long serialVersionUID = 1L;

/**
 * @see HttpServlet#HttpServlet()
 */
public SessionUsingHttpSessionRedirected() {
    super();
    // TODO Auto-generated constructor stub
}

/**
 * @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
 */
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
    // TODO Auto-generated method stub
    response.setContentType("html/text");
    PrintWriter out = response.getWriter();
    HttpSession session = request.getSession();
    String user = (String) request.getAttribute("user");
    out.print("Hello"+user);

}

}

and this is for view part

// UsingHttpSession.html

<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN"    "http://www.w3.org/TR/html4/loose.dtd">
<html>
<head>
<meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1">
<title>Insert title here</title>
</head>
<body>
<form method="get" action="SessionUsingHttpSession">
Enter Name:<input type="text" name="txtName4"/><br/>
Password: <input type="text" name="txtPassword4"/><br/>
<input type="Submit" value="Enter">
</form>
</body>
</html>

while i am trying to run it through apache tomcat server my web browsers(mozila,chrome,IE) showing this message: 在此处输入图片说明

if i save and open it it is giving "hello null" as output. Now my question is that why its showing such message as i am just trying to forward this page to another.

Thank you in advance.

Answer 1

Your content type appears reversed, you have it as html/text , instead of text/html .

Also it's a good habbit to flush/close stream after you write.

out.print("Hello"+user);
out.flush();
out.close();

Answer 2

The content type is wrong in both servlets. It should be text/html .

Moreover is you are using SessionUsingHttpSession servlet just for redirection then there is no need for specifying the content type at all.

using httpsession for session management

Question

2 answers

solution1
0 2013-12-02 16:24:27

solution2
0 ACCPTED 2013-12-02 16:27:55

using httpsession for session management

Question

2 answers

solution1 0 2013-12-02 16:24:27

solution2 0 ACCPTED 2013-12-02 16:27:55

solution1
0 2013-12-02 16:24:27

solution2
0 ACCPTED 2013-12-02 16:27:55