public static Path generatePath(Path basePath, String dumpFilePrefix,
      Byte tag, String bigBucketFileName) {
    return new Path(basePath, "MapJoin-" + dumpFilePrefix + tag +
      "-" + bigBucketFileName + suffix);
  }
Construct a list of full partition spec from Dynamic Partition Context and the directory names
corresponding to these dynamic partitions.
ql/src/java/org/apache/hadoop/hive/ql/exec/Utilities.java