}
int oldSize = this.size();
if (source instanceof IntBag)
{
IntBag otherBag = (IntBag) source;
otherBag.forEachWithOccurrences(new IntIntProcedure()
{
public void value(int each, int occurrences)
{
int oldOccurrences = IntHashBag.this.items.removeKeyIfAbsent(each, 0);
IntHashBag.this.size -= oldOccurrences;