public checkAndMutate_args setCompareOperator(@org.apache.thrift.annotation.Nullable TCompareOperator compareOperator) {
      this.compareOperator = compareOperator;
      return this;
    }
comparison to make on the value

@see TCompareOperator
hbase-thrift/src/main/java/org/apache/hadoop/hbase/thrift2/generated/THBaseService.java