Transport.send(message) not working in the below code.. netbeans gets stuck at the running part. it doesn't proceed furthur.. it hangs there forever

Question

I have tried to write a code to send email using Java. But this code is not working. When the code is executed it gets stuck at transport.send(message). It's stuck there forever. Also I am not sure if the rest of the code is correct or not.

  //first from, to, subject, & text values are set
    public class SendMail {
    private String from;
    private String to;
    private String subject;
    private String text;


    public SendMail(String from, String to, String subject, String text){
        this.from = from;
        this.to = to;
        this.subject = subject;
        this.text = text;
    }

    //send method is called in the end 
    public void send(){

        Properties props = new Properties();
        props.put("mail.smtp.host", "smtp.gmail.com");
        props.put("mail.smtp.port", "465");

        Session mailSession = Session.getDefaultInstance(props);
        Message simpleMessage = new MimeMessage(mailSession);

        InternetAddress fromAddress = null;
        InternetAddress toAddress = null;
        try {
            fromAddress = new InternetAddress(from);
            toAddress = new InternetAddress(to);
        } catch (AddressException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }

        try {
            simpleMessage.setFrom(fromAddress);
            simpleMessage.setRecipient(RecipientType.TO, toAddress);
            simpleMessage.setSubject(subject);
                    simpleMessage.setText(text);
            Transport.send(simpleMessage);  // this is where code hangs     
        } catch (MessagingException e) {
            // TODO Auto-generated catch block
            e.printStackTrace();
        }       
    }
}

Asiatic

Answer 1

I ran into exactly the same problem and others have reported intermittent failures. The reason is that Transport.send with SMTP has two infinite timeouts which can result in your process just hanging!

From SUN documentation:

mail.smtp.connectiontimeout int Socket connection timeout value in milliseconds. Default is infinite timeout.

mail.smtp.timeout int Socket I/O timeout value in milliseconds. Default is infinite timeout.

To not "hang" forever, you can set these explicitly:

From SUN: The properties are always set as strings; the Type column describes how the string is interpreted. For example, use

    props.put("mail.smtp.port", "888");

Note that if you're using the "smtps" protocol to access SMTP over SSL, all the properties would be named "mail.smtps.*".

So, if you set the two timeouts, you should get a "MessagingException" which you can process with a try/catch rather than having the process just hang.

Assuming that you are using smtp, add the following where t1 and t2 are your timeouts in ms:

    props.put("mail.smtp.connectiontimeout", "t1");
    props.put("mail.smtp.timeout", "t2");

Of course, this will not fix the root-cause for the timeouts, but it will let you handle the issues gracefully.

Thanks to Siegfried Goeschl's post on Apache Commons

PS: The root cause of problem I experienced seems tied to the network connection I was using while traveling. Apparently the connection was causing an SMTP timeout which I have not had with any other connections.

Stetson

Answer 2

Replace Session.getDefaultInstance with Session.getInstance.

If that doesn't solve the problem, read the JavaMail FAQ, which has debugging tips.

Misfeasor

i tried that and it still doesn't work. and sir i cant understand the documentation in javamail FAQ. i cannot understand that.i am still learning java. but still thanks for trying. – Asiatic

Answer 3

I had the exact same issue. I took me multiple hours to find the source of the problem. I was using the wrong dependency / dependency combination...

     <dependency>
        <groupId>javax.mail</groupId>
        <artifactId>javax.mail-api</artifactId>
        <version>1.6.1</version>
    </dependency>
    <dependency>
        <groupId>com.sun.mail</groupId>
        <artifactId>javax.mail</artifactId>
        <version>1.5.3</version>
    </dependency>

Changing it to ...

     <dependency>
        <groupId>javax.mail</groupId>
        <artifactId>javax.mail-api</artifactId>
        <version>1.5.3</version>
    </dependency>
    <dependency>
        <groupId>com.sun.mail</groupId>
        <artifactId>javax.mail</artifactId>
        <version>1.5.3</version>
    </dependency>

... solved the issue.

Jermainejerman

The javax.mail; includess the javax.mail.api. It worked fine for me once I got rid of javax-mail-api. I have just mail-1.5.0-b01.jar AND activation-1.1.1.JAR in my classpath and it works now! – Quantitative

Answer 4

I had AVG Free installed and it was blocking the email being sent.

Open AVG, go to Menu > Settings > Basic Protection > Email Shield

Uncheck "Scan Outbound Emails (SMTP)" and try run your program again.

Pest

Answer 5

Please try this,

    public class SMTPDemo {

  public static void main(String args[]) throws IOException,
      UnknownHostException {
    String msgFile = "file.txt";
    String from = "[email protected]";
    String to = "[email protected]";
    String mailHost = "yourHost";
    SMTP mail = new SMTP(mailHost);
    if (mail != null) {
      if (mail.send(new FileReader(msgFile), from, to)) {
        System.out.println("Mail sent.");
      } else {
        System.out.println("Connect to SMTP server failed!");
      }
    }
    System.out.println("Done.");
  }

  static class SMTP {
    private final static int SMTP_PORT = 25;

    InetAddress mailHost;

    InetAddress localhost;

    BufferedReader in;

    PrintWriter out;

    public SMTP(String host) throws UnknownHostException {
      mailHost = InetAddress.getByName(host);
      localhost = InetAddress.getLocalHost();
      System.out.println("mailhost = " + mailHost);
      System.out.println("localhost= " + localhost);
      System.out.println("SMTP constructor done\n");
    }

    public boolean send(FileReader msgFileReader, String from, String to)
        throws IOException {
      Socket smtpPipe;
      InputStream inn;
      OutputStream outt;
      BufferedReader msg;
      msg = new BufferedReader(msgFileReader);
      smtpPipe = new Socket(mailHost, SMTP_PORT);
      if (smtpPipe == null) {
        return false;
      }
      inn = smtpPipe.getInputStream();
      outt = smtpPipe.getOutputStream();
      in = new BufferedReader(new InputStreamReader(inn));
      out = new PrintWriter(new OutputStreamWriter(outt), true);
      if (inn == null || outt == null) {
        System.out.println("Failed to open streams to socket.");
        return false;
      }
      String initialID = in.readLine();
      System.out.println(initialID);
      System.out.println("HELO " + localhost.getHostName());
      out.println("HELO " + localhost.getHostName());
      String welcome = in.readLine();
      System.out.println(welcome);
      System.out.println("MAIL From:<" + from + ">");
      out.println("MAIL From:<" + from + ">");
      String senderOK = in.readLine();
      System.out.println(senderOK);
      System.out.println("RCPT TO:<" + to + ">");
      out.println("RCPT TO:<" + to + ">");
      String recipientOK = in.readLine();
      System.out.println(recipientOK);
      System.out.println("DATA");
      out.println("DATA");
      String line;
      while ((line = msg.readLine()) != null) {
        out.println(line);
      }
      System.out.println(".");
      out.println(".");
      String acceptedOK = in.readLine();
      System.out.println(acceptedOK);
      System.out.println("QUIT");
      out.println("QUIT");
      return true;
    }
  }
}

Irkutsk

this file that i am trying to send where does the code look for the file because it saying "java.io.FileNotFoundException: file.txt" – Asiatic

i managed to locate the file but after running the code now the following error comes:"java.net.ConnectException: Connection timed out: connect" – Asiatic

its giving me the following error "java.net.ConnectException: Connection timed out: connect" – Asiatic

and if i replace the port number 25 with 465 then it gets stuck again like the code i posted in the first place.. – Asiatic

i got solution to the connection getting stuck at transport.send(); – Asiatic

my port was being blocked by my firewall.. but still i get an error "connection refused " when i run my own code and i get an error "startTLS" should be enabled when i run your code. – Asiatic

Answer 6

Had this exact same problem. You have to close the transport in the catch block. The reason the code freezes is because the smtp server connection never gets shut down on the client side unless you do it manually.

    try {
        simpleMessage.setFrom(fromAddress);
        simpleMessage.setRecipient(RecipientType.TO, toAddress);
        simpleMessage.setSubject(subject);
                simpleMessage.setText(text);
        Transport.send(simpleMessage);  // this is where code hangs     
    } catch (MessagingException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
        Transport.close()
    } 

But the most efficient way to make sure javamail exits correctly is to bundle the javamail logic into one try block and close the transport in a finally block. Try this. [EDIT] After being alerted that the above code didn't work here is the code that compiles correctly.

import java.util.Properties;

import javax.mail.Message;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.Transport;
import javax.mail.Message.RecipientType;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;

//first from, to, subject, & text values are set

public class SendMail {
    private String from;
    private String to;
    private String subject;
    private String text;

    public SendMail(String from, String to, String subject, String text) {
            this.from = from;
            this.to = to;
        this.subject = subject;
            this.text = text;
    }

    // send method is called in the end
    public void send() throws MessagingException {

        Properties props = new Properties();
    props.put("mail.transport.protocol", "smtp");
    props.put("mail.smtp.host", "localhost");
    props.put("mail.smtp.auth", "false");// set to false for no username
    props.put("mail.debug", "false");
    props.put("mail.smtp.port", "25");

    Session session = Session.getDefaultInstance(props);

    InternetAddress fromAddress = null;
    InternetAddress toAddress = null;
    Transport transport = session.getTransport("smtp");
    transport.connect();
    try {
        Message simpleMessage = new MimeMessage(session);
        fromAddress = new InternetAddress(from);
        toAddress = new InternetAddress(to);
        simpleMessage.setFrom(fromAddress);
        simpleMessage.setRecipient(RecipientType.TO, toAddress);
        simpleMessage.setSubject(subject);
        simpleMessage.setText(text);
        transport.sendMessage(simpleMessage,
                simpleMessage.getAllRecipients());
    } catch (MessagingException e) {
        e.printStackTrace();
    } finally {
        transport.close();
    }
     }
 }

Halt

Have you tried running this code? The finally does not work because 'transport' should be 'Transport', and also because you cannot make a static reference to close(). – Gatt

Hi, thanks for pointing that out. I created an object with import javax.mail.Transport; and that allows you to close it in the finally block. I will edit this. – Halt

You should try actually running this code, there are a few issues with the way you have it now. – Gatt

Answer 7

1. Disable all the Antivirus programs.
2. Disable the Firewall.

Then give a try, if you succeed, investigate further to find the culprit.

In my case it was the Antivirus, and I had to make an exception for outbound mails on SMTP to send the mail successfully.

Shainashaine

Answer 8

When you Declare Transport.send() it will not work use this instead of transport.sendMessage(message, message.getAllRecipients()); and also declare a javax.mail.Transport transport = session.getTransport("smtp"); object as shown in the code.

       javax.mail.Transport transport = session.getTransport("smtp");
 transport.sendMessage(message,message.getAllRecipients());

then the following code will appear like this Thank you, hope this will work perfectly

package org.java.vamsi;
//import javax.activation.*;

import java.io.IOException;
import java.io.PrintWriter;
import java.util.Properties;
//import java.io.*;
//import javax.mail.internet.*;
import javax.mail.MessagingException;
import javax.mail.Session;
import javax.mail.internet.InternetAddress;
import javax.mail.internet.MimeMessage;
import javax.servlet.ServletException;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import javax.mail.Message.RecipientType;
//import com.sun.corba.se.impl.protocol.giopmsgheaders.Message;

//import java.io.*;
//import java.util.*;
//import javax.servlet.*;
//import javax.servlet.http.*;
//import javax.mail.*;
//import javax.mail.internet.*;
//import javax.activation.*;



//import sun.rmi.transport.Transport;

public class SendEmail extends HttpServlet {
    private static final long serialVersionUID = 1L;

        public void doGet(HttpServletRequest request,
                HttpServletResponse response)
        throws ServletException, IOException
{
  // Recipient's email ID needs to be mentioned.
  String to = "[email protected]";

  // Sender's email ID needs to be mentioned
  String from = "[email protected]";

  // Assuming you are sending email from localhost
  String host = "localhost";

  // Get system properties
  Properties properties = System.getProperties();

  // Setup mail server
  properties.setProperty("mail.smtp.host", host);

  // Get the default Session object.
  Session session = Session.getDefaultInstance(properties);

  // Set response content type
  response.setContentType("text/html");
  PrintWriter out = response.getWriter();

  try{
      javax.mail.Transport transport = session.getTransport("smtp");
     // Create a default MimeMessage object.
     MimeMessage message = new MimeMessage(session);
     // Set From: header field of the header.
     message.setFrom(new InternetAddress(from));
     // Set To: header field of the header.
     message.addRecipient(RecipientType.TO,
                              new InternetAddress(to));//as we are importing the "javax.mail.Message.RecipientType"
     //we have to not set the type as this message.addRecipient(Message.RecipientType.TO,
     //new InternetAddress(to));

     // Set Subject: header field
     message.setSubject("This is the Subject Line!");
     // Now set the actual message
     message.setText("This is actual message");
     // Send message
     transport.sendMessage(message,
             message.getAllRecipients());
     String title = "Send Email";
     String res = "Sent message successfully....";
     String docType =
     "<!doctype html public \"-//w3c//dtd html 4.0 " +
     "transitional//en\">\n";
     out.println(docType +
     "<html>\n" +
     "<head><title>" + title + "</title></head>\n" +
     "<body bgcolor=\"#f0f0f0\">\n" +
     "<h1 align=\"center\">" + title + "</h1>\n" +
     "<p align=\"center\">" + res + "</p>\n" +
     "</body></html>");
  }catch (MessagingException mex) {
     mex.printStackTrace();
  }
}           
    }

Buffet

Answer 9

I have code stuck on submit in IntelliJ. When I tried my code on this site: https://www.jdoodle.com/iembed/v0/mBA I got: Exception in thread "main" java.lang.NoClassDefFoundError: com/sun/mail/util/MailLogger The solution was to add this

<dependency>
    <groupId>com.sun.mail</groupId>
    <artifactId>javax.mail</artifactId>
    <version>1.6.2</version>
</dependency>

It's strange that IntelliJ didn't report this exception.

Colorant

Answer 10

For some odd reason, Avast was blocking the program, idk why. I deactivated it, restarted my IDE, and it worked. Try it out.

Circumbendibus