How to convert int[] to Set in Java

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How to convert int[] to Set< Integer> in Java

To Set< Integer> before JDK8

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public static Set<Integer> toSet(int[] nums) {
    Set<Integer> set = new HashSet<>();
    for (int num : nums) {
        set.add(num);
    }
    return set;
}

To Set< Integer> After JDK8

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public static Set<Integer> toSet(int[] nums) {
    return Arrays.stream(nums).boxed().collect(Collectors.toSet());
}

To TreeSet< Integer>

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public static TreeSet<Integer> toSet(int[] nums) {
    return Arrays.stream(nums).boxed().collect(Collectors.toCollection(TreeSet::new));
}

To ArrayList< Integer>

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public static List<Integer> toList(int[] nums) {
    return Arrays.stream(nums).boxed().collect(Collectors.toList());
}