This section provides a tutorial example on how to step through execution statements of the child thread in a multi-thread application.
2. Stepping through statements in the sub thread:
Thread-0[1] where all
Signal Dispatcher:
Finalizer:
[1] java.lang.Object.wait (native method)
[2] java.lang.ref.ReferenceQueue.remove (ReferenceQueue.java:111)
[3] java.lang.ref.ReferenceQueue.remove (ReferenceQueue.java:127)
[4] java.lang.ref.Finalizer$FinalizerThread.run (Finalizer.java:...
Reference Handler:
[1] java.lang.Object.wait (native method)
[2] java.lang.Object.wait (Object.java:429)
[3] java.lang.ref.Reference$ReferenceHandler.run (Reference.java...
main:
[1] java.lang.Thread.sleep (native method)
[2] PrimeNumberSeeker.main (PrimeNumberSeeker.java:21)
Thread-0:
[1] PrimeNumberSeeker.run (PrimeNumberSeeker.java:28)
Thread-0[1] next
2, 2, 0
>
Step completed: "thread=Thread-0", PrimeNumberSeeker.run(), line=29
29 while (count < ceiling) {
Thread-0[1] where all
...
main:
[1] java.lang.Thread.sleep (native method)
[2] PrimeNumberSeeker.main (PrimeNumberSeeker.java:21)
Thread-0:
[1] PrimeNumberSeeker.run (PrimeNumberSeeker.java:29)
Thread-0[1] next
3, 2, 0
>
30 current++;
Thread-0[1] next
4, 3, 0
>
31 int j = 2;
Thread-0[1] next
> 5, 3, 0
32 boolean isPrime = true;
Thread-0[1] next
6, 3, 0
>
33 while (j<current/2 && isPrime) {
Thread-0[1] list
29 while (count < ceiling) {
30 current++;
31 int j = 2;
32 boolean isPrime = true;
33 => while (j<current/2 && isPrime) {
34 isPrime = current % j > 0;
35 j++;
36 }
37 if (isPrime) {
38 count++;
Thread-0[1] print current
current = 3
What I have done here:
I used "where all" to display the current location of all threads.
Then I used "next" to execute one statement in the current thread, the sub thread, going from line 28
to line 29.
The next "where all" command showed me that the main thread went through an entire iteration of the
"while" loop. The main thread stopped again at line 21.
Then I used a couple of "next" command in the sub thread to bring the execution to line 33. At the
same time, the main thread went through a couple of iterations, printed some output messages.
Then I used "print" to check the current value of variable "current". Value 3 is correct.
