Java int[] array to HashSet

Question

I have an array of int:

int[] a = {1, 2, 3};

I need a typed set from it:

Set s;

If I do th

Answer 1

Another option would be to use a primitive set from Eclipse Collections. You can easily convert an int[] to a MutableIntSet to a Set or Integer[] as shown below, or you can use the MutableIntSet as is which will be much more memory efficient and performant.

int[] a = {1, 2, 3};
MutableIntSet intSet = IntSets.mutable.with(a);
Set integerSet = intSet.collect(i -> i);  // auto-boxing
Integer[] integerArray = integerSet.toArray(new Integer[]{});

If you want to go directly from the int array to the Integer array and preserve order, then this will work.

Integer[] integers = 
        IntLists.mutable.with(a).collect(i -> i).toArray(new Integer[]{});

Note: I am a committer for Eclipse Collections