生成指定范围的随机数

public class GenerateRandomNextInt {
    public static void main(String[] args) {
        int leftLimit = 2;
        int rightLimit = 11;

        Random random = new Random();
        Runnable r = () -> {
            int generatedInteger = leftLimit + random.nextInt(rightLimit - leftLimit + 1);
            System.out.println(generatedInteger);
        };
       for (int i = 1; i < 10; i++) {
           new Thread(r).start();
       }
    }
}