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Wouldn't it be easier to just use:

public static class IntArrayProcessor {
 private Integer[] arr;
 public IntArrayProcessor(Integer[] arr) {
 this.arr = arr;
 }
 public Integer[] unique() {
 final Set<Integer> uniqueSet = new HashSet<Integer>(Arrays.asList(this.arr));
 return uniqueSet.toArray(new Integer[uniqueSet.size()]);
 }
}

I changed the method name from getSet() to the more descriptive unique().

This simply generates a hash set, which contains only the unique values of the array. The hash set (uniqueSet) is then converted from Set to Integer[], and returned.

Given that this is using built-in methods and objects, it would likely be faster than most custom implementations.

Notice that HashSet:

makes no guarantees as to the insertion order of the set; in particular it does not guarantee that the order will remain constant over time.

— HashSet documentation

If you need to keep insertion order, use LinkedHashSet as suggested in @mrblewog's comment. If you want to have the internal Set sorted, use SortedSet or TreeSet.

I also changed int[] to Integer[] so that it can be used with generics (generics do not support primitive types).

Wouldn't it be easier to just use:

public static class IntArrayProcessor {
 private Integer[] arr;
 public IntArrayProcessor(Integer[] arr) {
 this.arr = arr;
 }
 public Integer[] unique() {
 final Set<Integer> uniqueSet = new HashSet<Integer>(Arrays.asList(this.arr));
 return uniqueSet.toArray(new Integer[uniqueSet.size()]);
 }
}

I changed the method name from getSet() to the more descriptive unique().

This simply generates a hash set, which contains only the unique values of the array. The hash set (uniqueSet) is then converted from Set to Integer[], and returned.

Given that this is using built-in methods and objects, it would likely be faster than most custom implementations.

Notice that HashSet:

makes no guarantees as to the insertion order of the set; in particular it does not guarantee that the order will remain constant over time.

— HashSet documentation

If you need to keep insertion order, use LinkedHashSet as suggested in @mrblewog's comment. If you want to have the internal Set sorted, use SortedSet or TreeSet.

I also changed int[] to Integer[] so that it can be used with generics (generics do not support primitive types).

Wouldn't it be easier to just use:

public static class IntArrayProcessor {
 private Integer[] arr;
 public IntArrayProcessor(Integer[] arr) {
 this.arr = arr;
 }
 public Integer[] unique() {
 final Set<Integer> uniqueSet = new HashSet<Integer>(Arrays.asList(this.arr));
 return uniqueSet.toArray(new Integer[uniqueSet.size()]);
 }
}

I changed the method name from getSet() to the more descriptive unique().

This simply generates a hash set, which contains only the unique values of the array. The hash set (uniqueSet) is then converted from Set to Integer[], and returned.

Given that this is using built-in methods and objects, it would likely be faster than most custom implementations.

Notice that it returns a sorted array, rather than an unsorted one. I also changed int[] to Integer[] so that it can be used with generics (generics do not support primitive types).

Wouldn't it be easier to just use:

public static class IntArrayProcessor {
 private Integer[] arr;
 public IntArrayProcessor(Integer[] arr) {
 this.arr = arr;
 }
 public Integer[] unique() {
 final Set<Integer> uniqueSet = new HashSet<Integer>(Arrays.asList(this.arr));
 return uniqueSet.toArray(new Integer[uniqueSet.size()]);
 }
}

I changed the method name from getSet() to the more descriptive unique().

This simply generates a hash set, which contains only the unique values of the array. The hash set (uniqueSet) is then converted from Set to Integer[], and returned.

Given that this is using built-in methods and objects, it would likely be faster than most custom implementations.

Notice that HashSet:

makes no guarantees as to the insertion order of the set; in particular it does not guarantee that the order will remain constant over time.

— HashSet documentation

If you need to keep insertion order, use LinkedHashSet as suggested in @mrblewog's comment. If you want to have the internal Set sorted, use SortedSet or TreeSet.

I also changed int[] to Integer[] so that it can be used with generics (generics do not support primitive types).

Wouldn't it be easier to just use:

public static class IntArrayProcessor {
 private Integer[] arr;
 public IntArrayProcessor(Integer[] arr) {
 this.arr = arr;
 }
 public Integer[] unique() {
 final Set<Integer> uniqueSet = new HashSet<Integer>(Arrays.asList(this.arr));
 return uniqueSet.toArray(new Integer[uniqueSet.size()]);
 }
}

I changed the method name from getSet() to the more descriptive unique().

This simply generates a hash set, which contains only the unique values of the array. The hash set (uniqueSet) is then converted from Set to Integer[], and returned.

Given that this is using build-in methods and objects, it would likely be faster than most custom implementations.

Notice that it returns a sorted array, rather than an unsorted one. I also changed int[] to Integer[] so that I can be used with generics (generics do not support primitive types).

Wouldn't it be easier to just use:

public static class IntArrayProcessor {
 private Integer[] arr;
 public IntArrayProcessor(Integer[] arr) {
 this.arr = arr;
 }
 public Integer[] unique() {
 final Set<Integer> uniqueSet = new HashSet<Integer>(Arrays.asList(this.arr));
 return uniqueSet.toArray(new Integer[uniqueSet.size()]);
 }
}

I changed the method name from getSet() to the more descriptive unique().

This simply generates a hash set, which contains only the unique values of the array. The hash set (uniqueSet) is then converted from Set to Integer[], and returned.

Given that this is using built-in methods and objects, it would likely be faster than most custom implementations.

Notice that it returns a sorted array, rather than an unsorted one. I also changed int[] to Integer[] so that it can be used with generics (generics do not support primitive types).