thread priority question...

[Padhu Vinirs]

JDK 1.4 on WinXP. I have 2 threads started from the main thread. I would
like to print some status of the child threads from the main thread
periodically. But I dont see the main thread to print out anything when the
child threads are running. The child threads do sleep after some work.
Instead should I make the child threads wait() and make the main thread
notifyAll() after printing ?

public class MainThread {
WorkerThread t1, t2;
public static void main(String[] args) {
new MainThread().st art();
}

public void start() {
t1 = new WorkerThread();
t2 = new WorkerThread();
t1.start();
t2.start();
// even this is not printed...
System.out.prin tln("print");
printWorkerStat us();
}

public void printWorkerStat us() {
while ( t1.isAlive() || t2.isAlive() ) {
t1.printStatus( ); // this print never happens
t2.printStatus( ); // this print never happens
Thread.sleep(40 *1000);
}
}
}

[Marek Puchalski]

Re: thread priority question...

Padhu Vinirs wrote:
[color=blue]
> public void printWorkerStat us() {
> while ( t1.isAlive() || t2.isAlive() ) {
> t1.printStatus( ); // this print never happens
> t2.printStatus( ); // this print never happens
> Thread.sleep(40 *1000);
> }[/color]

This code will not compile. Thread.sleep method throws an
InterruptedExce ption which is not handeled anywhere. Fix it. The rest of
the code seems ok. Should you have more problems, post the content of
the printStatus method.

Hope this helps

Marek

--
# You can't run away. Everyone's connected.
# Marek Puchalski
# Proud linux user: 409592

[Padhu Vinirs]

Re: thread priority question...


This was sample code I typed in here. Please assume that the exceptions are
caught etc. printStatus is very simple:

public void printStatus() {
// some system.out of thread's state variables...
}

Thanks

-- padhu

"Marek Puchalski" <marpuch+news@g mail.com> wrote in message
news:dumiqo$1kq a$1@node3.news. atman.pl...[color=blue]
> Padhu Vinirs wrote:
>[color=green]
>> public void printWorkerStat us() {
>> while ( t1.isAlive() || t2.isAlive() ) {
>> t1.printStatus( ); // this print never happens
>> t2.printStatus( ); // this print never happens
>> Thread.sleep(40 *1000);
>> }[/color]
>
> This code will not compile. Thread.sleep method throws an
> InterruptedExce ption which is not handeled anywhere. Fix it. The rest of
> the code seems ok. Should you have more problems, post the content of the
> printStatus method.
>
> Hope this helps
>
> Marek
>
> --
> # You can't run away. Everyone's connected.
> # Marek Puchalski
> # Proud linux user: 409592[/color]

[Marek Puchalski]

Re: thread priority question...

Padhu Vinirs wrote:[color=blue]
> This was sample code I typed in here. Please assume that the exceptions are
> caught etc. printStatus is very simple:
>
> public void printStatus() {
> // some system.out of thread's state variables...
> }[/color]

It's a pain to try to find bugs in a sample code. See this. It works fine.

class WorkerThread extends Thread
{
public void run()
{
while ( true )
;
}

public void printStatus()
{
System.out.prin tln( 111 );
}
}

public class MainThread
{
WorkerThread t1, t2;

public static void main( String[] args )
{
new MainThread().st art();
}

public void start()
{
t1 = new WorkerThread();
t2 = new WorkerThread();
t1.start();
t2.start();
// even this is not printed...
System.out.prin tln( "print" );
printWorkerStat us();
}

public void printWorkerStat us()
{
while ( t1.isAlive() || t2.isAlive() )
{
t1.printStatus( ); // this print never happens
t2.printStatus( ); // this print never happens
try
{
Thread.sleep( 40 * 1000 );
}
catch ( InterruptedExce ption e )
{
// TODO Auto-generated catch block
e.printStackTra ce();
}
}
}
}

and the output is like:

print
111
111
111
111 (...)

Hope this helps.

Marek

--
# You can't run away. Everyone's connected.
# Marek Puchalski
# Proud linux user: 409592

[Oliver Wong]

Re: thread priority question...


"Padhu Vinirs" <prabha_pady@co mcast.net> wrote in message
news:sOadnXdHBf ETT5PZRVn-tA@comcast.com. ..[color=blue]
>
> This was sample code I typed in here. Please assume that the exceptions
> are caught etc. printStatus is very simple:
>
> public void printStatus() {
> // some system.out of thread's state variables...
> }
>
> Thanks[/color]

If I assume you've done everything correctly, then yes, your code works
perfectly. Since it's not working perfectly, perhaps the assumption that
you've done everything correctly is invalid.

Please post an SSCCE. http://mindprod.com/jgloss/sscce.html

- Oliver

[Dobromir Gaydarov]

Re: thread priority question...

The MainThread is not properly coded to be a Thread - it does not
impletement the java.lang.Runna ble interface. If we assume you coded the
WorkerThread the same way your program executes sequentially and therefore
you will see your output from the main "thread" as soon as the child
"threads" complete.

Regards,
Dobromir

"Padhu Vinirs" <prabha_pady@co mcast.net> wrote in message
news:CuSdnTtRE9 a4WZPZRVn-qQ@comcast.com. ..[color=blue]
> JDK 1.4 on WinXP. I have 2 threads started from the main thread. I would
> like to print some status of the child threads from the main thread
> periodically. But I dont see the main thread to print out anything when
> the child threads are running. The child threads do sleep after some work.
> Instead should I make the child threads wait() and make the main thread
> notifyAll() after printing ?
>
> public class MainThread {
> WorkerThread t1, t2;
> public static void main(String[] args) {
> new MainThread().st art();
> }
>
> public void start() {
> t1 = new WorkerThread();
> t2 = new WorkerThread();
> t1.start();
> t2.start();
> // even this is not printed...
> System.out.prin tln("print");
> printWorkerStat us();
> }
>
> public void printWorkerStat us() {
> while ( t1.isAlive() || t2.isAlive() ) {
> t1.printStatus( ); // this print never happens
> t2.printStatus( ); // this print never happens
> Thread.sleep(40 *1000);
> }
> }
> }
>[/color]

[Padhu Vinirs]

Re: thread priority question...

The main thread is the starting class ( with the main method ). That is the
default thread. It doesnt need to implement Runnable. My question was
related to the main thread being able to print status of threads it started.

-- padhu

"Dobromir Gaydarov" <notme@sympatic o.ca> wrote in message
news:u7XPf.3149 $xM2.237984@new s20.bellglobal. com...[color=blue]
> The MainThread is not properly coded to be a Thread - it does not
> impletement the java.lang.Runna ble interface. If we assume you coded the
> WorkerThread the same way your program executes sequentially and therefore
> you will see your output from the main "thread" as soon as the child
> "threads" complete.
>
> Regards,
> Dobromir
>
> "Padhu Vinirs" <prabha_pady@co mcast.net> wrote in message
> news:CuSdnTtRE9 a4WZPZRVn-qQ@comcast.com. ..[color=green]
>> JDK 1.4 on WinXP. I have 2 threads started from the main thread. I would
>> like to print some status of the child threads from the main thread
>> periodically. But I dont see the main thread to print out anything when
>> the child threads are running. The child threads do sleep after some
>> work. Instead should I make the child threads wait() and make the main
>> thread notifyAll() after printing ?
>>
>> public class MainThread {
>> WorkerThread t1, t2;
>> public static void main(String[] args) {
>> new MainThread().st art();
>> }
>>
>> public void start() {
>> t1 = new WorkerThread();
>> t2 = new WorkerThread();
>> t1.start();
>> t2.start();
>> // even this is not printed...
>> System.out.prin tln("print");
>> printWorkerStat us();
>> }
>>
>> public void printWorkerStat us() {
>> while ( t1.isAlive() || t2.isAlive() ) {
>> t1.printStatus( ); // this print never happens
>> t2.printStatus( ); // this print never happens
>> Thread.sleep(40 *1000);
>> }
>> }
>> }
>>[/color]
>
>[/color]