HttpSession Interface
Container creates a session id for each user. The container uses this id to identify the particular user.
An object of HttpSession can be used to perform two tasks:
- bind objects
- view and manipulate information about a session, such as the session identifier, creation time, and last accessed time
| Method |
Description |
| public HttpSession getSession() |
Returns the current session associated with this request, or if the request does not have a session, creates one |
| public HttpSession getSession(boolean create) |
Returns the current HttpSession associated with this request or, if there is no current session and create is true, returns a new session |
| public String getId() |
Returns a string containing the unique identifier value |
| public long getCreationTime() |
returns the time when this session was created, measured in milliseconds since midnight January 1, 1970 GMT |
| public long getLastAccessedTime() |
Returns the last time the client sent a request associated with this session, as the number of milliseconds since midnight January 1, 1970 GMT. |
| public void invalidate() |
Invalidates this session then unbinds any objects bound to it |
Example Code
| FirstServlet.java |
|
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class FirstServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response){
try{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
String n=request.getParameter("userName");
out.print("Welcome "+n);
HttpSession session=request.getSession();
session.setAttribute("uname",n);
out.print("<a href='servlet2'>visit</a>");
out.close();
}catch(Exception e){System.out.println(e);}
}
}
|
| SecondServlet.java |
|
import java.io.*;
import javax.servlet.*;
import javax.servlet.http.*;
public class SecondServlet extends HttpServlet {
public void doGet(HttpServletRequest request, HttpServletResponse response){
try{
response.setContentType("text/html");
PrintWriter out = response.getWriter();
HttpSession session=request.getSession(false);
String n=(String)session.getAttribute("uname");
out.print("Hello "+n);
out.close();
}catch(Exception e){System.out.println(e);}
}
}
|
| index.html |
|
<form action="servlet1">
Name:<input type="text" name="userName"/><br/>
<input type="submit" value="go"/>
</form>
|
| web.xml |
|
<?xml version="1.0"?>
<web-app>
<servlet>
<servlet-name>s1</servlet-name>
<servlet-class>FirstServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>s1</servlet-name>
<url-pattern>/servlet1</url-pattern>
</servlet-mapping>
<servlet>
<servlet-name>s2</servlet-name>
<servlet-class>SecondServlet</servlet-class>
</servlet>
<servlet-mapping>
<servlet-name>s2</servlet-name>
<url-pattern>/servlet2</url-pattern>
</servlet-mapping>
</web-app>
|
Output
For more RTU V Sem Advance Java Lab Experiments Click here
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