public boolean retainAll(ByteIterable source)
{
int oldSize = this.size();
final ByteSet sourceSet = source instanceof ByteSet ? (ByteSet) source : source.toSet();
ByteIntHashMap retained = ByteIntHashMap.this.select(new ByteIntPredicate()
{
public boolean accept(byte key, int value)
{
return sourceSet.contains(key);
}