LongXorReduce extends ReduceSameTypeOperation<LongWritable> { @Override public LongWritable createInitialValue() { return new LongWritable(0L); } LongXorReduce(); @Override LongWritable createInitialValue(); @Override LongWritable reduce(LongWritable curValue,
      LongWritable valueToReduce); @Override void write(DataOutput out); @Override void readFields(DataInput in); static final LongXorReduce INSTANCE; }
@Test public void testZero() { Assert.assertEquals(0b0L, xor.createInitialValue().get()); }