code: public final void findCallingMethodsInDir(final File dir, final FileFilter filter) {
  
          final FileProcessor fileProcessor = new FileProcessor(new FileHandler() {
              @Override
              public final FileHandlerResult handleFile(final File file) {
                  if (file.isDirectory()) {
                      return FileHandlerResult.CONTINUE;
                  }
                  if (file.getName().endsWith(".class") && (filter == null || filter.accept(file))) {
                      handleClass(file);
                  }
                  return FileHandlerResult.CONTINUE;
              }
          });
          fileProcessor.process(dir);
  
      }
docs: Locate method calls in classes of a directory.
  
  @param dir
  Directory to search (including sub directories).
  @param filter
  File filter or NULL (process all '*.class' files).