public static String normalizePartitionCase(String s) {
    if (s == null) {
      return null;
    }
    Map<String, String> map = Splitter.on(Path.SEPARATOR).withKeyValueSeparator('=').split(s);
    return FileUtils.makePartName(new ArrayList<>(map.keySet()), new ArrayList<>(map.values()));
  }
A helper method to return SQL's 'IS NULL'
clause whenever input is NULL.
@param input A string to be compared to null.
@return String
standalone-metastore/metastore-server/src/main/java/org/apache/hadoop/hive/metastore/txn/TxnUtils.java