public int reduceValuesToInt(long parallelismThreshold,
                                 ToIntFunction<? super V> transformer,
                                 int basis,
                                 IntBinaryOperator reducer) {
        if (transformer == null || reducer == null)
            throw new NullPointerException();
        return new MapReduceValuesToIntTask<K,V>
            (null, batchFor(parallelismThreshold), 0, 0, table,
             null, transformer, basis, reducer).invoke();
    }
public int reduceValuesToInt(long parallelismThreshold,
                                 ToIntFunction<? super V> transformer,
                                 int basis,
                                 IntBinaryOperator reducer)