Servlet thread programming

Hello,
I have a non-blocking IO channel server that gets instantiated through a thread. The server has to listen for a pre-specified number of clinet connections and close down. This is repeated a few times. The servlet calls two separate threads. One of the two threads calls the server.
The server works just fine till the time it is called from a tomcat servlet. On being called from a servlet the first time, the server starts listening, formats and displays the output correctly. However, the socket does not stop listening on the port[I have specifically put socket.close() in there]. As a result the next socket that gets started, simply dies due a bind error.
The code works perfectly outside the web-container (tomcat) environment.
Also, the ethereal output for both connections is identical; no extra FIN-ACKs or ACKs flying through.
Thanks in anticipation.

I tried increasing the value of the loop as suggested in the earlier mail, but that just kept the server hanging even after all communications.
Just noticed something funky. The servlet page sends the HTTP page to the requesting web-client immediately after the Fin ACK from the TCP client. The server then ACks the FIN ACK but never sends a FIN ACK back to the client. This causes the server to stay up. If the HTTP page is not served out immediately, the communication ends properly.
Any clue on how to do this?
Thanks

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Purush,
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Hi there,
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public class DataGenerator implements Runnable {
int nImageWidth;
int nImageHeight;
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Sorry about that, didnt realise.
Hi there,
Probably a fairly simple one here (quite new to java), i'm trying to do some thread programming but I get this error.
ThreadController.java:42: variable dataGeneratorThread might not have been initialized
The bit I dont understand is that I run
this line here
this line here
for(int i=0; i < JuliaFrame.NO_OF_DATA_GENERATORS; i++){
dataGenerators = new DataGenerator(JuliaFrame.ImageWidth,JuliaFrame.ImageHeight,inputBuffer);
dataGeneratorThread = new WorkerThread(dataGenerators,juliaCalc,displayBuffer);
dataGeneratorThread.start();
}but when I do
dataGeneratorThread.activeCount() is balks.
I check that the thread is alive first but dont no how to tell the compiler this - obviously NO_OF_DATA_GENERATORS could be 0 in which case the compiler would have issues - I just wish it was more trusting ;)
Here is some of the code
runable class{
new Thread( new ThreadController(inputBuffer,displayBuffer,juliaCalc) ).start();
public class ThreadController implements Runnable {
DataBuffer inputBuffer;
DataBuffer displayBuffer;
JuliaCalc juliaCalc;
/** Creates a new instance of ThreadController */
public ThreadController(DataBuffer inputBuffer,DataBuffer displayBuffer,JuliaCalc juliaCalc) {
inputBuffer = inputBuffer;
displayBuffer = displayBuffer;
juliaCalc = juliaCalc;
public void run()
DataGenerator[] dataGenerators = new DataGenerator[JuliaFrame.NO_OF_DATA_GENERATORS];
WorkerThread dataGeneratorThread;
for(int i=0; i < JuliaFrame.NO_OF_DATA_GENERATORS; i++){
dataGenerators = new DataGenerator(JuliaFrame.ImageWidth,JuliaFrame.ImageHeight,inputBuffer);
dataGeneratorThread = new WorkerThread(dataGenerators,juliaCalc,displayBuffer);
dataGeneratorThread.start();
dataGeneratorThread.activeCount();
int nNanoSecsBeforeCheck = 50;
while(true)
if(dataGeneratorThread.isAlive()){
if(dataGeneratorThread.activeCount() > inputBuffer.size())
public class DataGenerator implements Runnable {
int nImageWidth;
int nImageHeight;
DataBuffer inputBuffer;
public DataGenerator(int ImageWidth, int ImageHeight,DataBuffer inputBuffer) {
nImageWidth = ImageWidth;
nImageHeight = ImageHeight;
public void run()
// Non terminating thread - created datapakets and place them in the input buffer
// Get two radom number withoin a bound and find out bout default highest colou - 3rd value
while(true)
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nRandomYCord = ((int)(Math.random() * nImageHeight));
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inputBuffer.put(dpDataPacket);
}

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To get better help sooner, post a SSCCE that clearly demonstrates the problem.
Use 2 to 4 spaces, not tabs, for indentation. Most members won't take the trouble to read code that is too deeeply indented. I know I don't.
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