public boolean isSet(_Fields field) {
    if (field == null) {
      throw new java.lang.IllegalArgumentException();
    }

    switch (field) {
    case NAME:
      return isSetName();
    case MAX_VERSIONS:
      return isSetMaxVersions();
    case COMPRESSION:
      return isSetCompression();
    case IN_MEMORY:
      return isSetInMemory();
    case BLOOM_FILTER_TYPE:
      return isSetBloomFilterType();
    case BLOOM_FILTER_VECTOR_SIZE:
      return isSetBloomFilterVectorSize();
    case BLOOM_FILTER_NB_HASHES:
      return isSetBloomFilterNbHashes();
    case BLOCK_CACHE_ENABLED:
      return isSetBlockCacheEnabled();
    case TIME_TO_LIVE:
      return isSetTimeToLive();
    }
    throw new java.lang.IllegalStateException();
  }
Returns true if field corresponding to fieldID is set (has been assigned a value) and false otherwise
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/generated/ColumnDescriptor.java