public void add(Cell cell) {
    /*
     * For faster hashing, use combinatorial generation
     * http://www.eecs.harvard.edu/~kirsch/pubs/bbbf/esa06.pdf
     */
    int hash1;
    int hash2;
    HashKey<Cell> hashKey;
    if (this.bloomType == BloomType.ROWCOL) {
      hashKey = new RowColBloomHashKey(cell);
      hash1 = this.hash.hash(hashKey, 0);
      hash2 = this.hash.hash(hashKey, hash1);
    } else {
      hashKey = new RowBloomHashKey(cell);
      hash1 = this.hash.hash(hashKey, 0);
      hash2 = this.hash.hash(hashKey, hash1);
    }
    setHashLoc(hash1, hash2);
  }
Creates another similar Bloom filter. Does not copy the actual bits, and sets the new filter's
key count to zero.
@return a Bloom filter with the same configuration as this
hbase-server/src/main/java/org/apache/hadoop/hbase/util/BloomFilterChunk.java