code: private File extractThriftFile(String artifactId, String fileName, Set<File> thriftFiles) {
      for (File thriftFile : thriftFiles) {
        boolean fileFound = false;
        if (fileName.equals(thriftFile.getName())) {
          for (String pathComponent : thriftFile.getPath().split(File.separator)) {
            if (pathComponent.equals(artifactId)) {
              fileFound = true;
            }
          }
        }
  
        if (fileFound) {
          return thriftFile;
        }
      }
      return null;
    }
docs: Picks out a File from `thriftFiles` corresponding to a given artifact ID
  and file name. Returns null if `artifactId` and `fileName` do not map to a
  thrift file path.
  
  @parameter artifactId The artifact ID of which to look up the path
  @parameter fileName the name of the thrift file for which to extract a path
  @parameter thriftFiles The set of Thrift files in which to lookup the
  artifact ID.
  @return The path of the directory containing Thrift files for the given
  artifact ID. null if artifact ID not found.