public Combination<Colors> generate(){
    List<Token<Colors>> combination = new ArrayList<Token<Colors>>(); 
    
    List<Colors> colors = Colors.getColors();
    
    Random r = new Random();    
    for (int i = 0; i < Combination.SIZE; i++) {
      int n = r.nextInt(colors.size());
      combination.add(new Token<Colors>(colors.get(n)));
      colors.remove(n);
    }
		
   return new Combination<Colors>(combination);
  }