Return ArrayList from method in Java

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Hi,

I have a method in Java that returns a List, and it can return null:

Java

public List<Player> route(String message, double[] destination)
{
  List<Player> tempList = new ArrayList<Player>();

 if (.....)
   return null;
 else
  {
     tempList.add(p1);
     tempList.add(p2);
  }

return tempList
}

Now I want to add it to my ArrayList, but it doesn't work.
I do it like this:

Java

myList.addall(route(........);

but it doesn't work. (probably because I return null sometimes).

What do I do wrong?
How should I do it correctly?

Thanks

Posted 22-Apr-12 12:00pm

user_code

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Comments

Sergey Alexandrovich Kryukov 22-Apr-12 19:31pm

What is really written in this line with "......". It would not compile... must be "addAll", for example. :-)
Do the actual types of a generic parameter match?
--SA

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TorstenH. · Accepted Answer · 2012-04-22T22:20:00

Solution 1

return an empty ArrayList:

Java

if(condition){
  return new ArrayList<player>();
}
</player>

That is much easier to deal with on the receiving side.

Posted 22-Apr-12 22:20pm

TorstenH.