@NotNull
  private static Collection<File> findPossibleSourcesForClass(JavaSourceRootDescriptor rd, final @Nullable String boundClassName) throws IOException {
    if (boundClassName == null) {
      return Collections.emptyList();
    }
    String relPath = suggestRelativePath(rd, boundClassName);
    final File containingDirectory = new File(rd.getRootFile(), relPath).getParentFile();
    if (containingDirectory == null) {
      return Collections.emptyList();
    }
    final File[] files = containingDirectory.listFiles(FileFilters.withExtension("java"));
    if (files == null || files.length == 0) {
      return Collections.emptyList();
    }
    return Arrays.asList(files);
  }
@NotNull
  private static Collection<File> findPossibleSourcesForClass(JavaSourceRootDescriptor rd, final @Nullable String boundClassName)