public boolean isSetNumVersions() {
      return org.apache.thrift.EncodingUtils.testBit(__isset_bitfield, __NUMVERSIONS_ISSET_ID);
    }
Returns true if field numVersions is set (has been assigned a value) and false otherwise
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift/generated/Hbase.java