code: private static List<CopyPath> expandSingle(Path src, Path dstPath)
        throws IOException {
      List<Path> expandedPaths = new ArrayList<Path>();
      FileSystem fs = src.getFileSystem(defaultConf);
      FileStatus[] stats = fs.globStatus(src);
      if (stats == null || stats.length == 0) {
        throw new IOException("Path : " + src + " is invalid");
      }
      for (FileStatus stat : stats) {
        expandedPaths.add(stat.getPath());
      }
      List<CopyPath> expandedDirs = expandDirectories(fs, expandedPaths, dstPath);
      return expandedDirs;
    }
docs: Expand a single file, if its a file pattern list out all files matching the
  pattern, if its a directory return all files under the directory.
  
  @param src
  the file to be expanded
  @param dstPath
  the destination
  @return the expanded file list for this file/filepattern
  @throws IOException