code: public Map<String, Class<?>> defineClasses(Map<String, byte[]> typeDefinitions) throws ClassNotFoundException {
          if (sealed) {
              throw new IllegalStateException("Cannot inject classes into a sealed class loader");
          }
          return doDefineClasses(typeDefinitions);
      }
docs: Defines a group of types to be loaded by this class loader. If this class loader is sealed, an {@link IllegalStateException} is thrown.
  
  @param typeDefinitions The types binary representations.
  @return The mapping of defined classes or previously defined classes by their name.
  @throws ClassNotFoundException If the class could not be loaded.