使用Hutool中的RandomUtil.weightRandom方法，生成帶有權重的隨機值

import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
import cn.hutool.core.lang.WeightRandom;
import cn.hutool.core.lang.WeightRandom.WeightObj;
import cn.hutool.core.util.RandomUtil;

public class Demo {
	public static void main(String[] args) {
		List<WeightRandom.WeightObj<String>> weightList = new ArrayList<WeightRandom.WeightObj<String>>();
		WeightRandom.WeightObj<String> a = new WeightObj<String>("A", 1);
		WeightRandom.WeightObj<String> b = new WeightObj<String>("B", 2);
		WeightRandom.WeightObj<String> c = new WeightObj<String>("C", 3);
		WeightRandom.WeightObj<String> d = new WeightObj<String>("D", 4);
		weightList.add(a);
		weightList.add(b);
		weightList.add(c);
		weightList.add(d);
		WeightRandom wr = RandomUtil.weightRandom(weightList);
		String str = "";
		int num_a = 0, num_b = 0, num_c = 0, num_d = 0;
		for (int i = 0; i < 100000; i++) {
			str = wr.next().toString();
			switch (str) {
			case "A":
				num_a = num_a+1;
				break;
			case "B":
				num_b = num_b+1;
				break;
			case "C":
				num_c = num_c+1;
				break;
			case "D":
				num_d = num_d+1;
				break;
			}
			//System.out.println(str);
		}
		System.out.println("A---------"+num_a);
		System.out.println("B---------"+num_b);
		System.out.println("C---------"+num_c);
		System.out.println("D---------"+num_d);
	}

}

運行結果：