code: @Override
  	public void releaseSlot(@Nonnull SlotRequestId slotRequestId, @Nullable Throwable cause) {
  
  		componentMainThreadExecutor.assertRunningInMainThread();
  
  		log.debug("Releasing slot [{}] because: {}", slotRequestId, cause != null ? cause.getMessage() : "null");
  		releaseSingleSlot(slotRequestId, cause);
  	}
docs: ------------------------------------------------------------------------