Question

In C++, I can use find_if with a predicate to find an element in a container. Is there something like that in Java? The contains method on collections uses equals and can not be parameterized.

Answer 1

You can use Predicate from Google Collections. Here is the tutorial and an example from it:

final Predicate<Car> expensiveCar = new Predicate<Car>() {
   public boolean apply(Car car) {
      return car.price > 50000;
   }
}

List<Car> cars = Lists.newArrayList();
cars.add(new Car("Ford Taurus", 20000));
cars.add(new Car("Tesla", 90000));
cars.add(new Car("Toyota Camry", 25000));
cars.add(new Car("McClaren F1", 600000));

final List<Car> premiumCars =
   Lists.immutableList(Iterables.filter(cars, expensiveCar));

You can also look at this thread: What is the best way to filter a Collection?