Doubts in threads !

[Manoj Chandran]

Hello,
look at this code:
class A{
public static void main(String s[]){
System.out.println("Hello");
}
}
My question is how many threads run concurrently(including JVM and gc)while executing the above code?
Plz give an elaborate reply..
Thanking in advance..,
Manoj

[Anshuman Acharya]

in this program the only non-daemon thread is the main thread.
there may be n numbers of daemon threads, of which gc is one example. the jvm exists only when all the non-daemon threads are dead. as for daemon threads, they are system threads and don't belong to a process as such.

[Manoj Chandran]

Hi Anshuman,
Can u plz differentiate between daemon n non daemon threads?
Manoj

[Anshuman Acharya]

I am giving a reference Baldwin's Java Tutorial
Daemon Threads
According to Java Primer Plus, if you set a thread as a daemon thread using setDaemon() method, you are
specifying that the thread belongs to the system and not to the process that spawned it.Daemon threads
are useful if you want a thread to run in the background for extended periods of time.
According to Deitel and Deitel, Java, How to Program, "A daemon thread is a thread that runs for the
benefit of other threads."
Daemon threads run in the background and do not prevent a program from terminating. For example, the
garbage collector is a daemon thread.
A program can include a mixture of daemon and non-daemon threads. The Java virtual machine will exit
when only daemon threads remain in a program.

satisfied?