1.数组转List集合

​Integer[] a = {1,2,3};
        List<Integer> collect =
                Arrays.stream(a).collect(Collectors.toList());
        if (collect.contains(1)){
            System.out.println("正确");
        }

​

2.List集合转数组

List<Integer> list = Arrays.asList(1,2,3,4);
        System.out.println(list);
        Object[] array = list.toArray();
        System.out.println(Arrays.toString(array));