code: public Map<String, Class<?>> scan(String classNamePattern) throws IOException {
          final Map<String, Class<?>> scannedClasses = new LinkedHashMap<>();
          scan(classNamePattern, scannedClasses);
          return scannedClasses;
      }
docs: Find all classes that match the class name pattern.
  
  @param classNamePattern the class name pattern
  @return a Map for scanned classes
  @throws IOException if an I/O error has occurred