The Balancer controls the maximum of concurrent threads in the current Scheduler(s) and prevents
from own thread resources exhaustion if other group of schedulers share the same pool of threads.
Handles responses from concurrent junit
Stuff to remember about JUnit threading:
parallel=classes; beforeClass/afterClass, constructor and all tests method run on same thread
parallel=methods; beforeClass/afterClass run on main thread, constructor + each test method run on same thread
parallel=both; same as parallel=methods
Noteworthy things about JUnit4 listening:
A class that is annotated with @Ignore will have one invocation of "testSkipped" with source==name
A method that is annotated with @Ignore will have a invocation of testSkipped with source and name distinct
Methods annotated with @Ignore trigger no further events.
Attempts to stop all actively executing tasks and immediately returns a collection
of descriptions of those tasks which have started prior to this call.