Question

I would like to return an arraylist from a non-class method in java, i have searched around but found nothing so far.

{
     int d=e.length();
     ArrayList list2 = new ArrayList();
     for (int i=0;i<d;i++)
     {
         list2.add('_');
     }
     return list2;
}

Thanks alot!

Answer 1

All you need to do is put the return type in the signature, and then return the list

public class Example {
    // a static method
    public static List someStaticMethod(){
       // create and return a List
    }

    // this method is not static
    public List someMethod(){
       // create and return a List
    }

}

Note that because ArrayList extends List you can make the return type either one of those.

List is more generic, you can return any type of list. This is useful because if you want to change the internal list that you use (say change from ArrayList to LinkedList) you won’t have to change your API everywhere you use the method.

However, if you use a list implementation that has its own methods that are not defined by the List interface, you won’t be able to access those methods when you get the list back from your method, unless you either cast (ewe) or specify the exact return type.