@Override
  public DropPartitionMessage buildDropPartitionMessage(Table table, Iterator<Partition> partitions) {
    return new JSONDropPartitionMessage(HCAT_SERVER_URL, HCAT_SERVICE_PRINCIPAL, table.getDbName(),
        table.getTableName(), table.getTableType(),
        MessageBuilder.getPartitionKeyValues(table, partitions), now());
  }
The JSON implementation of the MessageFactory. Constructs JSON implementations of
each message-type.
hcatalog/server-extensions/src/main/java/org/apache/hive/hcatalog/messaging/json/JSONMessageFactory.java