public static void addLibrary(Class<?> libraryClass)
			throws SoundSystemException {
		if (libraryClass == null)
			throw new SoundSystemException(
					"Parameter null in method 'addLibrary'",
					SoundSystemException.NULL_PARAMETER);
		if (!Library.class.isAssignableFrom(libraryClass))
			throw new SoundSystemException("The specified class does not "
					+ "extend class 'Library' in method 'addLibrary'");

		if (libraries == null)
			libraries = new LinkedList<Class<?>>();

		if (!libraries.contains(libraryClass))
			libraries.add(libraryClass);
	}