- protected AbstractDOMForwardedCompositeTransaction(final Object identifier, final ImmutableMap<K, T> backingTxs) {
- this.identifier = Preconditions.checkNotNull(identifier, "Identifier should not be null");
- this.backingTxs = Preconditions.checkNotNull(backingTxs, "Backing transactions should not be null");
+ protected AbstractDOMForwardedCompositeTransaction(final Object identifier, final Map<K, T> backingTxs) {
+ this.identifier = requireNonNull(identifier, "Identifier should not be null");
+ this.backingTxs = requireNonNull(backingTxs, "Backing transactions should not be null");