Idle socket causing delayed data transfer

Question

I have a telnet type client written that has a thread to continually read data from the socket with the server. The problem is, that when the connection is idle for a significant amount of time (no data transfered), the connection enters "delay state" (that's what I'll call it). In this state, if data were to begin transferring again, nothing is read from the InputStream until a while later (minutes).
From my observations, I believe the delay time reduces if more data is queued up.
Here is my thread code:
          public void run() {     
               inputField.requestFocusInWindow();
               if(!init()) return;
               byte[] buff=new byte[buf_size];
               int nch;
               thread:while(this==Thread.currentThread()) {
                    try {
                         if ((nch = in.read(buff, 0, buff.length)) == -1) {
                              addMessage("Natural disconnection from host.");
                              disconnect();
                              break thread;
                         outputArea.append(buff,nch);
                    } catch(Exception e) {
                         if(e instanceof IOException)
                              addMessage("Forcibly disconnected from host.");
                         else if(e instanceof DataFormatException)
                              addMessage("Fatal error - data corrupted. Disconnecting.");
                         else  //else I don't know what happened, so print the raw data
                              addMessage(e.toString());
                         disconnect();
                         break thread;
          }You'll notice a lot of references to my own methods. I think their naming is fairly self explanatory, but if you need clarification, feel free to ask.
Message was edited by:
natmaster

Answer 1

With ejp's pedigree on this forum, i think he understands threads!
<p>I think you've misinterpreted that tutorial. In the tutorial i found this code:
<p>
public void run() {<br>
��Thread myThread = Thread.currentThread();<br>
��while (clockThread == myThread) {<br>
����repaint();<br>
����try {<br>
������Thread.sleep(1000);<br>
����} catch (InterruptedException e) {<br>
������//The VM doesn't want us to sleep anymore,<br>
������//so get back to work.<br>
����}<br>
��}<br>
<p>which i presume you're referring to, but that only works because the code is run from an applet with a stop method that sets clockThread to null. It's nothing to do with fairness of executing threads.
<p>Think about which thread is executing the statement "this == Thread.currentThread". Unless you're calling this run method from yet another unspecified thread, it's going to be "this", and if "this" is having a chance to execute any statements at all, then it's also going to be the current thread, so that statement will always be true.
<p>If you want to be sure to be nice to other threads, you could call Thread.yield(). I never had much joy with using this method though, and the current JVMs seem to be pretty good at being fair to all threads even if none of them sleep or yield at all
<p>
[Sorry about formatting, damned forum seems to be shagged to tried to do it manually with html tags]