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javamultithreadingforkjoinpool

what does the number mean in current thread name?

I have a question about Thread while developing Java applications.

The code below is the result of a printout of the code into the thread.currentThread();

Thread[ForkJoinPool-1-worker-2,5,main]

Does 1 mean the index of the pool?

Does 2 mean worker number?

I don't know exactly the number meaning of 1, 2, 5.

Thanks.

Solution

  • if you look in ForkJoinPull class you can find one of many constructors

    ForkJoinPool(...){
  ....
  this.workerNamePrefix = "ForkJoinPool-" + nextPoolId() + "-worker-";
  ....
}

    wherenextPoolId() it's poolNumberSequence. After initialization workerNamePrefix will has next value - "ForkJoinPool-1-worker-...". after that in method final WorkQueue registerWorker(ForkJoinWorkerThread wt) {} will set thread name in string 1414 (wt.setName(prefix.concat(Integer.toString(tid)))) where wt is ForkJoinWorkerThread and tid are thread's pids. This name you showed in your output.