package pl.net.bluesoft.util.lang.cquery;
import pl.net.bluesoft.util.lang.cquery.func.F;
import java.util.Comparator;
/**
* User: POlszewski
* Date: 2011-07-29
* Time: 19:14:14
*/
final class AscendingComparator<T, R extends Comparable<R>> implements Comparator<T> {
private final F<? super T, R> selector;
public AscendingComparator(F<? super T, R> selector) {
this.selector = selector;
}
@Override
public int compare(T x, T y) {
if (x == y) {
return 0;
}
R sx = selector.invoke(x);
R sy = selector.invoke(y);
if (sx == sy) {
return 0;
}
if (sx == null) {
return +1;
}
if (sy == null) {
return -1;
}
return +sx.compareTo(sy);
}
}