How to quit with a locked thread around ?

[Patrick Stadelmann]

Hi,

How can I force my application to quit when it has a "locked" thread ?
The lockup is caused by attempting to use a Virtual COM port when no
device is connected. I can detect the lockup and live with it, however
it prevents my application from exiting when I return from "main".

Thanks,

Patrick

 

[Owen Jacobson]

Hi,

How can I force my application to quit when it has a "locked" thread ?
The lockup is caused by attempting to use a Virtual COM port when no
device is connected. I can detect the lockup and live with it, however
it prevents my application from exiting when I return from "main".

In addition to exiting when all non-daemon threads terminate, the JVM
will also exit when certain methods are called:

<http://java.sun.com/javase/6/docs/api/java/lang/
System.html#exit(int)>

-o

 

[Knute Johnson]

Hi,

How can I force my application to quit when it has a "locked" thread ?
The lockup is caused by attempting to use a Virtual COM port when no
device is connected. I can detect the lockup and live with it, however
it prevents my application from exiting when I return from "main".

Thanks,

Patrick

The best option would be to get the 'locked' thread to return. Maybe
you could timeout the call to use the COM port and force the return.
The other option is to specifically call System.exit() when you are done.

 

[Thomas Kellerer]

Patrick Stadelmann wrote on 07.05.2008 22:02:

Hi,

How can I force my application to quit when it has a "locked" thread ?
The lockup is caused by attempting to use a Virtual COM port when no
device is connected. I can detect the lockup and live with it, however
it prevents my application from exiting when I return from "main".

Run that thread as a daemon thread. After creating the Thread instance and
before starting the thread call setDaemon(true)

 

[Patrick Stadelmann]

In addition to exiting when all non-daemon threads terminate, the JVM
will also exit when certain methods are called:

<http://java.sun.com/javase/6/docs/api/java/lang/
System.html#exit(int)>

This worked, thanks.

The best option would be to get the 'locked' thread to return. Maybe
you could timeout the call to use the COM port and force the return.

I tried this first, but to no avail. The lockup occurs when writing to
the output stream with certain Virtual COM port, and I couldn't find a
way to set the write operation to timeout.

The other option is to specifically call System.exit() when you are done.

Thanks, it worked.

Run that thread as a daemon thread. After creating the Thread instance and
before starting the thread call setDaemon(true)

This did not work, but thanks anyway !

Patrick

 

[Arne Vajhøj]

This worked, thanks.

But it is a rather hard way of closing down. It may be fine
for your app, but ther are certinly apps where it would
not be good.

Arne

 

[Chronic Philharmonic]

Unfortunately, when a thread is running deep in the guts of native code, it
might not respond to standard Java thread attention getters, such as
interrupting the thread or marking it as a daemon. For example, this can be
a problem for threads blocked in socket reads. Sometimes you can break the
thread loose by closing the socket from another thread, but it can be
implementation and/or platform dependent even then.