六个不重复随机数数组

public class ArrayTest {
    public static void main(String[] args) {
        int[] arr = new int[6];
        int i = 0;
        label: while (i < 6) {
            int num = (int) (Math.random() * 30 + 1);
            arr[i] = num;
            for (int j = 0; j < i; j++) {
                if (arr[j] == arr[i]) {
                    continue label;
                }
            }
            i++;
        }
        for (int j = 0; j < 6; j++) {
            System.out.print(arr[j] + "\t");
        }
    }
}