code: @SuppressWarnings("unchecked")
      private static <T> Class<T> getClass(String className)
      {
          if (CLASS_CACHE.containsKey(className))
          {
              return (Class<T>) CLASS_CACHE.get(className);
          }
          try
          {
              final Class<?> clazz = LOADER.loadClass(className);
              CLASS_CACHE.put(className, clazz);
              return (Class<T>) clazz;
          }
          catch (final ClassNotFoundException exception)
          {
              throw new LionEngineException(exception, ERROR_CLASS_PRESENCE + className);
          }
      }
docs: Get the class reference from its name using cache.
  
  @param <T> The class type.
  @param className The class name.
  @return The typed class instance.
  @throws LionEngineException If invalid class.