code: public KeyGroupRangeOffsets getIntersection(KeyGroupRange keyGroupRange) {
  		Preconditions.checkNotNull(keyGroupRange);
  		KeyGroupRange intersection = this.keyGroupRange.getIntersection(keyGroupRange);
  		long[] subOffsets = new long[intersection.getNumberOfKeyGroups()];
  		if(subOffsets.length > 0) {
  			System.arraycopy(
  					offsets,
  					computeKeyGroupIndex(intersection.getStartKeyGroup()),
  					subOffsets,
  					0,
  					subOffsets.length);
  		}
  		return new KeyGroupRangeOffsets(intersection, subOffsets);
  	}
docs: Returns a key-group range with offsets which is the intersection of the internal key-group range with the given
  key-group range.
  
  @param keyGroupRange Key-group range to intersect with the internal key-group range.
  @return The key-group range with offsets for the intersection of the internal key-group range with the given
  key-group range.