几种方法，其中一种，类似于您的方法
private enum Type{ TYPE_A(10 ), TYPE_B(1), TYPE_C(5), TYPE_D(20), TYPE_E(7);private int weight;private Type(int weight) { this.weight = weight;}private int getWeight() { return weight;} private static final List<Type> VALUES = Collections.unmodifiableList(Arrays.asList(values())); private int summWeigts() { int summ = 0; foreach(Type value: VALUES)summ += value.getWeight(); return summ; } private static final int SIZE = summWeigts(); private static final Random RANDOM = new Random(); public static Type randomType() { int randomNum = RANDOM.nextInt(SIZE); int currentWeightSumm = 0; for(Type currentValue: VALUES) {if (randomNum > currentWeightSumm && randomNum <= (currentWeightSumm + currentValue.getWeight()) { break;}currentWeightSumm += currentValue.getWeight(); } return currentValue.get(); }}
