If not already completed, sets the value returned by {@link
#get()} and related methods to the given value.
@param value the result value
@return {@code true} if this invocation caused this CompletableFuture
to transition to a completed state, else {@code false}
If not already completed, sets the value returned by {@link #get()} and related methods to the given value.
@param value the result value @return {@code true} if this invocation caused this CompletableFuture to transition to a completed state, else {@code false}