What number of threads does ForkJoinPool use by default to execute tasks?

By default, ForkJoinPool in Java creates a number of threads equal to the number of available processor cores, which can be obtained through Runtime.getRuntime().availableProcessors().

This is done to optimize resource utilization, avoid excessive context switching, and ensure maximum performance when executing parallel tasks.

Example of obtaining the default number of threads:

int parallelism = ForkJoinPool.commonPool().getParallelism();
System.out.println("Default number of threads: " + parallelism);

If needed, you can create a ForkJoinPool with a different level of parallelism by specifying the desired number of threads in the constructor.