can we add primitive variables in ArrayList or just objects?

[Vishal Hegde]

can we add primitive variables in arraylist or just objects

[Chinna Eranna]

You can add *only* objects.

You can use.. wrapper classes.. for store the primitive data.

[Karthick Dharani Vidhya]

With the AUTO BOXING feature, the below code will work fine

  ArrayList a = new ArrayList();
        a.add(1);
        a.add(2);
        a.add(3);
        a.add(4);
        a.add(5);  

But even though you add primitive ones here, Auto boxing is done and all these values are added as Integer objects

[Vishal Hegde]

Karthick Dharani Vidhya wrote:With the AUTO BOXING feature, the below code will work fine

  ArrayList a = new ArrayList();
        a.add(1);
        a.add(2);
        a.add(3);
        a.add(4);
        a.add(5);  

But even though you add primitive ones here, Auto boxing is done and all these values are added as Integer objects

why aint you used

ArrayList<Integer>a=new ArrayList<Integer>();

[Karthick Dharani Vidhya]

Should have used it. Thanks.

[Campbell Ritchie]

Vishal Hegde wrote:why aint you used

ArrayList<Integer>a=new ArrayList<Integer>();

Surely you mean this?

List<Integer>iList=new ArrayList<Integer>();

[Vishal Hegde]

Ritchie sir , arent both correct?

i mean

ArrayList<Integer>a=new ArrayList<Integer>(); //as arraylist is a class

List<Integer>iList=new ArrayList<Integer>(); //list is an interface

[Janeice DelVecchio]

Vishal Hegde wrote:Ritchie sir , arent both correct?

i mean

ArrayList<Integer>a=new ArrayList<Integer>(); //as arraylist is a class

List<Integer>iList=new ArrayList<Integer>(); //list is an interface

Campbell's solution is best. It is my understanding that you should always code to an interface (when possible) and not its implementation.

I think this allows for greater flexibility if you need to change something down the line.