How to instantiate fields?

Hi
I am unsure how you should instantiate an instance field. I have seen it two ways
private List<Car> cars;
public CarMaker()
cars = new ArrayList<Car>();
...Or this way
private List<Car> cars = new ArrayList<Car>();
contructor here
...What is the difference and what should I normally do?

You've got the terminology wrong:
instantiate = Create an object of a type. You instanciate classes.
initialize = set to some defined value. You initialize fields.
As to your question:
if a field is initialized the same way for each constructor and doesn't need any of the parameters of the constructor for initialization, then I'd use the second way.

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