public void initMasks(String query) {
    queryMasks.clear();
    for (Mask m : Mask.values()) {
      if (m.existsIn(query)) {
        queryMasks.add(m);
      }
    }
  }
Pattern to match and (partial) replacement text.
For example, {"transaction":76,"bucketid":8249877}.  We just want to mask 76 but a regex that
matches just 76 will match a lot of other things.
itests/util/src/main/java/org/apache/hadoop/hive/ql/QOutProcessor.java