Java EE (Java Enterprise Edition) General Discussion

import javax.servlet.*;

import javax.servlet.http.*;

import java.io.*;

import javax.mail.*;
import javax.mail.Authenticator;
import javax.mail.PasswordAuthentication;
   
import javax.mail.internet.*;   // important

import javax.mail.event.*;      // important

import java.net.*;

import java.util.*;

public class MailServlet extends HttpServlet 

{

    public  void doGet(HttpServletRequest request,HttpServletResponse response)

                                  throws ServletException, IOException
  
    {
       System.out.println("Inside the MailServlet....");
       response.setContentType("text/html");
       PrintWriter out=response.getWriter();
        try

        { 
	      java.security.Security.addProvider(new com.sun.net.ssl.internal.ssl.Provider());
           Properties props=new Properties();

           props.put("mail.smtp.host","smtp.gmail.com");   //  'localhost' for testing
           props.put("mail.smtp.port","587");
   	       props.put("mail.debug", "true");
    	   props.put("mail.smtp.auth", "true"); 
           props.put("mail.smtp.starttls.enable", "true");
   		   
            
           String hst =System.getProperty( "mail.smtp.host");
           if( hst != null)
           {
               props.put( "mail.smtp.host", "smtp.gmail.com");
               props.put("mail.smtp.port","587");
                
           } 
           Session session1=Session.getInstance(props,null);

           String name = request.getParameter("name"); //sender (from)
           String organization = request.getParameter("organization");
           String designation = request.getParameter("designation");
           String telephone = request.getParameter("telephone");
           String city = request.getParameter("city");
           String message = request.getParameter("message");
            
 	System.out.println("Name----"+name);
	System.out.println("organization---"+organization);
	System.out.println("designation---"+designation);
 	System.out.println("telephone---"+telephone);
 	System.out.println("city---"+city);
 	System.out.println("message---"+message);
 
    MimeMessage message1 = new MimeMessage(session1);
    message1.setFrom(new InternetAddress("shivankagrawal@gmail.com"));
    message1.setRecipients(Message.RecipientType.TO,InternetAddress.parse("shivank_be@yahoo.co.in",false));
    message1.setSubject("Hi this is testing mail");
    message1.setContent("khana", "text/plain"); 
    //Transport.send(message1);
    Transport tr = session1.getTransport("smtp");	
    //tr.send(message1); 
 
    String smtpHost="smtp.gmail.com";
    String mailID="shivankagrawal@gmail.com";
    String password="swamiji";
    
    tr.connect(smtpHost, mailID, password);
    message1.saveChanges();
    tr.sendMessage(message1, message1.getAllRecipients());//this the line where i get the error as mentioned in Subject line
    tr.close();
    
     out.println("mail has been sent");

        }   
        catch(Exception es)
	    {
        	es.printStackTrace();
        	 System.out.println("ERROR....."+es);
	    }
    
    }
  }