How to hold the main thread, till response is received from the server?

I have a program in which the GUI client(View program in Swings) sends a request to server (Manager program) , and waits for the response from Manager.
The method used is waitForResponse() as follows
<code>
private void waitForResponse()
m_blWaitFlag=true;
//after response from manager m_blWait flag is set to false.
while (m_blWaitFlag)
try
Thread.sleep(500);
}catch(Exception r_ex)
</code>
And in notifyResponse() method, the wait flag is set to false
as in,
<code>
public void notifyResponse(VcvResponse r_objResponse)
m_blWaitFlag = false; //this line makes the thread to come out of the wait mode.
</code>
When I click a menu item, this request is sent and there is a wait for a response from manager.
The problem is , this kind of waiting makes the system slow, and grey patches are seen immediately after clicking a menu item.
Are there other ways of waiting??
Thanks in advance

When I click a menu item, this request is sent and there is a wait for a response from manager.This means you are using the GUI thread to send the request.
The problem is , this kind of waiting makes the system slow, and grey patches are seen immediately after clicking a menu item.This means the GUI thread is waiting for the response. No GUI updates can occur while it is waiting.
Are there other ways of waiting??Use another thread. e.g the main as you suggested. If you are using a callback, why do you have a thread waiting at all? WHy not do the things you would do when a response comes back in the call back?

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Itunes could not connect to the ipad because an invalid response was received from the device

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Waiting the main thread till all child thread has completed

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Thanks.

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private boolean myStopFlag;
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How to make the main() thread wait?

I would like to know how to make the main() thread wait for another thread?If I use wait() method in main() method it says "non-static method wait() cannot be referenced from a static context",since main()
is static.

Here is an example how you may wait for a Thread in the main -
but be careful, this is no real OO:
public class WaitMain {
// this is the thread class - you may also create
// a runnable - I use a inner class to
// keep my example simple
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                    sleep(10000);
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                    sleep(10000);
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// this is the object we wait for -
// it is just a synchronizer, nothing else
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// this will wait for the notify
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Hello,
I have a multi-threaded application but the main thread doesnt blocks the application so the application quits just after started. Im using this code to block the main thread:
/*BufferedReader r = new BufferedReader(new InputStreamReader(System.in));
for(;;) {
try {
r.readLine();
catch (IOException e) {
I tryed to just use for(;;){} but it causes 100% of CPU using. This code above its very dangerous because sometimes System.in blocks the entire application (all threads)
Thanks a lot

This application its a socket server, Im doing:
main {
Thread1 - createServer();
Thread2 - createLogging();
waitForServerShutDown();
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I am trying to find an elegant way for a child thread (spawned from a main thread) to stop what its doing and tell the main thread something went wrong. I thought that if I invoke mainThread.interrupt() from the child thread by giving the child thread a reference to the main thread, that would do the trick. But it doesn't work all the time. I want to know why. Here's my code below:
The main class:
* IF YOU RUN THIS OFTEN ENOUGH, YOU'LL NOTICE THE "Child Please!" MESSAGE NOT SHOW AT SOME POINT. WHY?
public class InterruptingParentFromChildThread
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The class for the child thread:
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EJP wrote:
I'm not convinced about that. The wording in join() suggests that, but the wording in interrupt() definitely does not.Thread.join() doesn't really provide much in the way of details, but Object.wait() does:
"throws InterruptedException - if any thread interrupted the current thread +before+ or while the current thread was waiting for a notification. The interrupted status of the current thread is cleared when this exception is thrown."
every jdk method i've used which throws InterruptedException will always throw if entered while a thread is currently interrupted. admitted, i rarely use Thread.join(), so it's possible that method could be different. however, that makes the thread interruption far less useful if it's required to hit the thread while it's already paused.
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Thread.currentThread().interrupt();
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What exactly is the main thread?

please consider this code:
public class Foo {
    public static void main(String[] args) {
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"public void run();" method?
While I can't think of any practical usage of this knowledge yet, but I'd still like to know. Thanks.
Edited by: outekko on Mar 17, 2010 6:38 PM

joshg_75 wrote:
You should always refer to the javadoc for infomation of a method and its usage. In this case, refer to the javadoc of the Thread class.
http://java.sun.com/j2se/1.5.0/docs/api/java/lang/Thread.html
I suggest you also read up on usage of threads.Can you please share a little of your expertise in threads?
Remember this is the "New To Java" forum, and I am just a beginner as you discovered. Any help from experts would be embraced. Before you became a thread expert, you must have started somewhere. I don't need immediate assistance, but whenever you get the time, why not cut/paste this into your IDE and take a look.
public class Main {
static ObjectOutputStream oos;
static ObjectInputStream ois;
public static void main(String[] args) {
    try {
      PipedInputStream pin = new PipedInputStream();
      PipedOutputStream pout = new PipedOutputStream(pin);
      oos = new ObjectOutputStream(pout);
      ois = new ObjectInputStream(pin);
      new OutThread().start();
      for(;;) {
        Thread t = (Thread) ois.readObject();
        t.start();
    } catch (Exception e) { e.printStackTrace(); }
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        public void run() {
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}Not only do I appear to serialize instances of threads, the threads are actually running . So, does a live thread have private, non-transient, "state" that needs to be persisted? If so, why does serialization work? If not, why not write in the API that java.lang.Thread implements Serializable ? Whatever understanding (if any) I had of threads has melted to nothing. I am struggling with your field of expertise; please help me get back on track. Any assistance embraced.
ps. don't offer friendly criticism by scolding my design of serialized threads. My only goal is to see if I can do it (and learn something along the way).

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