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This noncompliant code snippet \[[Techtalk 07|AA. Java References#Techtalk 07]\] prints {{100}} as the size of the {{HashSet}} while it is expected to print {{1}}. The combination of a {{short}} and an  {{integer}} value in the operation {{i-1}} leads to autoboxing into an {{Integer}} object. The {{HashSet}} contains only {{short}} values whereas (distinctly typed) {{Integer}} objects are being removed successively. The remove operation is thus equivalent to a _No Operation_ (NOP). The compiler enforces type checking so that only {{short}} values are inserted, however, a programmer is free to remove an object of any type without triggering any exceptions since {{Collections<E>.remove}} takes an Object parameter and not {{E}}. Such behavior can result in unintended object retention or memory leaks.

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public class ShortSet {
  public static void main(String[] args) {
    HashSet<Short> s = new HashSet<Short>();
      for(short i=0; i<100;i++) {
        s.add(i);
        s.remove(i - i);
      }
    System.out.println(s.size());
  }
}

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