Exceptionally completes this CompletableFuture with
a {@link TimeoutException} if not otherwise completed
before the given timeout.
@param timeout how long to wait before completing exceptionally
with a TimeoutException, in units of {@code unit}
@param unit a {@code TimeUnit} determining how to interpret the
{@code timeout} parameter
@return this CompletableFuture
Exceptionally completes this CompletableFuture with a {@link TimeoutException} if not otherwise completed before the given timeout.
@param timeout how long to wait before completing exceptionally with a TimeoutException, in units of {@code unit} @param unit a {@code TimeUnit} determining how to interpret the {@code timeout} parameter @return this CompletableFuture