SERVLET TECHNOLOGY

Introduction to Attribute

An attribute is an object that is used to share information in a web app. Attribute allows Servlets to share information among themselves. Attributes can be SET and GET from one of the following scopes :

  1. request
  2. session
  3. application

setting and getting an attribute


How to SET an Attribute

public void setAttribute(String name, Object obj) method is used to SET an Attribute.

Example demonstrating Setting Attribute

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

public class First extends HttpServlet {

  protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        ServletContext sc = getServletContext();
        sc.setAttribute("user","Abhijit");	//setting attribute on context scope
    }
}

How to GET an Attribute

Object getAttribute(String name) method is used to GET an attribute.

Example demonstrating getting a value of set Attribute

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

public class Second extends HttpServlet {

  protected void doPost(HttpServletRequest request, HttpServletResponse response)
            throws ServletException, IOException {
        response.setContentType("text/html;charset=UTF-8");
        PrintWriter out = response.getWriter();
        ServletContext sc = getServletContext();
 
        String str = sc.getAttribute("user");  //getting attribute from context scope
	
        out.println("Welcome"+str);  // Prints : Welcome Abhijit   
    }
}