public void setKey(VectorMapJoinFastBytesHashMultiSetStore multiSetStore, long refWord) {

      // Preconditions.checkState(!KeyRef.getIsInvalidFlag(refWord));

      this.multiSetStore = multiSetStore;

      this.refWord = refWord;

      absoluteOffset = KeyRef.getAbsoluteOffset(refWord);

      // Position after next relative offset (fixed length) to the key.
      multiSetStore.writeBuffers.setReadPoint(absoluteOffset, readPos);

      keyLength = KeyRef.getSmallKeyLength(refWord);
      boolean isKeyLengthSmall = (keyLength != KeyRef.SmallKeyLength.allBitsOn);
      if (!isKeyLengthSmall) {

        // And, if current value is big we must read it.
        keyLength = multiSetStore.writeBuffers.readVInt(readPos);
      }

      // NOTE: Reading is now positioned before the key bytes.
    }
Setup for reading the key of an entry with the equalKey method.
@param multiSetStore
@param refWord
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/mapjoin/fast/VectorMapJoinFastBytesHashMultiSetStore.java