QCar $ = QCar.car;

Matcher

Car car = new Car().setHorsePower(123);
assertThat(car, hasValue($.horsePower, equalTo(123)));

Comparator

Car car = new Car().setHorsePower(50);
Car betterCar = new Car().setHorsePower(150);
assertEquals(-1, pathComparator($.horsePower).compare(car, betterCar));

Future ideas:
 - Sort definition: new MutableSortDefinition($.horsePower, true, true)
 - Bean wrapper: getPropertyDescriptor($.horsePower)
 - Sort builder: asc($.horsePower, $.model) -> Sort (Spring Data JPA)