public boolean retainAll(FloatIterable source)
{
int oldSize = this.size();
final FloatSet sourceSet = source instanceof FloatSet ? (FloatSet) source : source.toSet();
FloatFloatHashMap retained = FloatFloatHashMap.this.select(new FloatFloatPredicate()
{
public boolean accept(float key, float value)
{
return sourceSet.contains(value);
}