Where to put methods?

Question

Hi folks, this isn't a Java dependant question but since I am coding in Java I will ask it here. I have a value object that contains a few attributes, accessor and persistence methods. We'll call the Class Player and it contains details of a person who is playing a game. All of the methods and attributes belonging to this Class are related to an instance of Player. I want to have a utility method that returns ALL the players. What do people of the group think is the best way to treat this method? Should I add a new Class i.e. PlayerUtils, where I could subsequently add more utility methods OR would adding a method to the Player Class, public static Vector getAllPlayers() be a viable option? My gut feeling is to go with the PlayerUtils Class even though there is only one method so far because it is more flexbile and it keeps static method calls out of my instance Class. I don't really have any formal training in Java so most of what I have learned is through experience and reference-type books. Your thoughts are valued.
Thanks, Max

Answer 1

This is like a singleton, except it is a "multipleton". (I haven't studied my design patterns well yet, maybe it has a name.) I agree that keeping the collection information in another class might be a better idea, but this Player class could also do its own enforcing that certain Player fields (such as name) acts like primary keys and are not duplicated.
class Player
   // static field
   private static Vector allPlayers = new Vector();
   // private constr
   private Player(<args>)
   public static Player createNewPlayer(<args>)
      Player newguy = new Player(args);
      allPlayers.add(newguy);
      return newguy;
   public static Player getPlayerByName(String name)
      ... // assuming Player has a Name field, find him
   public static Vector getAllPlayers()
      return allPlayers;  // or a copy of it