java生成指定个数及区间范围的不重复随机数存入数组中

//打印数组内容
public void print(Integer[] arr) {
        if(arr != null) {
            for (int i = 0; i < arr.length; i++) {
                if(i == 0) {
                    System.out.print("[");
                }
                System.out.print(arr[i]);

                if(i == arr.length - 1) {
                    System.out.print("]");
                } else {
                    System.out.print(",");
                }

            }
        } else {
            System.out.println("arr is null");
        }
    }


    /**
     * 通过指定的多少内的随机数及生成个数及是否从0开始,返回不重复的随机数数组
     * @param randomVal --- 多少内的随机数
     * @param arrSize  --- 数组长度
     * @param startZero  --- 是否从0开始
     * @return
     * @throws IllegalAccessException
     */
    public Integer[] random(int randomVal, int arrSize, boolean startZero) throws IllegalAccessException {
        if(randomVal < arrSize) {
            throw new IllegalAccessException("randomVal can't less than arrSize");
        } else if (randomVal <= 0) {
            throw new IllegalAccessException("randomVal should more than 0");
        }

        Integer[] arr = new Integer[arrSize];

        for (int i = 0; true;) {
            int val = new Random().nextInt(randomVal);
            if(!startZero) {
                val += 1;
            }
            boolean hasExist = false;
            if(i > 0) {
                for(int j = i - 1; j >= 0; j --) {
                    if (val == arr[j]) {
                        hasExist = true;
                        break;
                    }
                }
            }

            if(!hasExist) {
                arr[i ++] = val;
            }
            if(i == arrSize) {
                break;
            }
        }
        return arr;
    }

调用方式

print(random(5, 5, false));   //随机结果的一种 [1,2,5,4,3] 
print(random(5, 5, true));   //随机结果的一种 [0,4,1,3,2] 
print(random(100, 5, true));  //随机结果的一种 [45,27,51,99,88]