实例化扩展 ArrayList 的类

Question

Is it possible to create an instance of a class extending of an ArrayList?

In the example below, how can I create an instance of class Cars containing all cars data? Is it possible this way, or do I have to remove inheritance and add a field in Cars class like --> private List Car listCars?

public class Cars extends ArrayList<Car>{
   public Cars() {}
}

public class Car {

    private String name;

    public String getName() {
        return name;
    }
    public void setName(String name) {
        this.name = name;
    }
}

Answer 1

You can extend ArrayList as it's not a final class and has visible constructors to call. In practice however one should favor composition over inheritance so below would be preferable:

public class Cars {
  private final List<Car> values = new ArrayList<>();

  public void add(Car c) {
    values.add(c);
  }
}