Returns a string representation of this FutureTask.
@implSpec
The default implementation returns a string identifying this
FutureTask, as well as its completion state. The state, in
brackets, contains one of the strings {@code "Completed Normally"},
{@code "Completed Exceptionally"}, {@code "Cancelled"}, or {@code
"Not completed"}.
@return a string representation of this FutureTask
Returns a string representation of this FutureTask.
@implSpec The default implementation returns a string identifying this FutureTask, as well as its completion state. The state, in brackets, contains one of the strings {@code "Completed Normally"}, {@code "Completed Exceptionally"}, {@code "Cancelled"}, or {@code "Not completed"}.
@return a string representation of this FutureTask