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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 values of types {{short}} and {{int}} in the operation {{i-1}} leads to autoboxing into an object of type {{Integer}}. The {{HashSet}} contains only values of type {{Short}} whereas the code attempts to remove objects of the (different) type {{Integer}}. As a result, the remove operation is 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 a parameter of type {{Object}} and not a parameter of type {{E}}. Such behavior can result in unintended object retention or memory leaks. \[[Techtalk 07|AA. Java References#Techtalk 07]\]

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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 - 1);
      }
    System.out.println(s.size());
  }
}

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