Websocket concurrent write not working 100% in java

Question

I have a websocket server that I have messages being sent to from a queue of bytebuffers in java. Here is the following code that sends the messages in the queue to the websocket server,

protected void dequeue() throws InterruptedException, IOException
{
    ByteBuffer bbuf;
    while((bbuf = messageQueue.take()).get(0) != 0)
    {
        bbuf.position(bbuf.limit());
        System.out.println(bbuf);
        bbuf.flip();
        for(Session session : sessionList)
        {
            session.getBasicRemote().sendBinary(bbuf);
        }
    }
}

However, when I try to write two messages concurrently from the queue there is not 100% reliability. Sometimes the first and second message get sent sometimes only the first message gets sent. I know that the message is getting sent due to that wireshark shows me the messages are being sent 100% of the time but not received every time as stated. Why might this being happening when I do concurrent writes on a websocket that the receiving end would not always receive the message? I am using tomcat 7.0.53

Answer 1

This is due to the following bug in tomcat, https://issues.apache.org/bugzilla/show_bug.cgi?id=57318#c1 updating to apache tomcat 7.0.57 will fix the issue. Updating to an apache tomcat version greater then 7.0.53 may fix the issue but has not been tested yet.