Using different constructors

Question

Hello all,
I have a class that can be instantiated with 2 different constructors, like this :
public class LProject {
private List projects;
public LProject(String path, String name) {
super(path, name);
projects = new ArrayList();
public LProject(String path, String name, String description) {
super(path, name, description);
}My question concerns the initialization of the ArrayList, if i first create an object with LProject(path, name) the ArrayList will be initialize, and the then if i create a second object with LProject(path, name, description), the ArrayList would still be usable or it would be null?
Do i have to initialize the ArrayList in both constructor? In this case it would give me two differents ArrayList so if i add the LProject object created before it will be in two different ArrayList?
It is not clear for me can somebody help me clear that out.
thanks a lot

Answer 1

I don't think that is thread safe.
If I was you I would do
private static List projects = new LinkedList();
Actually, that is not thread safe. But your example is not thread safe, either.
@OP: if you want to use this static list, do this:
private static List projects = Collections.synchronizedList(new ArrayList());But synchronization is not really necessary, if you keep this field as private and if you will not provide any kind of getter method that can return this list field (you can't guarantee what the other programmers will do with your list). If you decide to not use synchronization, you must guarantee that the manipulation of this list will only occur inside this class, where you can yourself control the access of this list. And you can achieve this control only by making this list totally unavailable to the others.
If you are expert in synchronization, then you can use a unsynchronized list, doing the control of the manipulation of this list by your own code inside your class. Otherwise, if you don't know very much about synchronization, although the cost of performance when synchronization is being used (not so much, but there is a cost), it is always safer using a synchronized list.