How to access individual values of an object that is stored in an array of similar objects in Java

Question

I am having a problem with trying to keep my coding organized and as simple as possible. I basically have an array of similar objects that hold multiple values. I am wanting to access those individual values and be able to modify them at will but cannot seem to acess them. This is what the code basically looks like...

    //In file Champion.java
    package Champions;
    public interface Champion{}

    //In another file ChoGath.java
    package Champions;
    public class ChoGath implements Champion{
    public static double health = 440.0;
    }

    //Yet another file Ahri.java
    package Champions;
    public class Ahri implements Champion{
    public static double health = 380.0;
    }

    //In the main build file LOLChampBuilder.java
    package LOLChampBuilder;
    import Champions.*;
    public class LOLChampBuilder{
        public static Champion[] listOfChampions = {new ChoGath(), new Ahri()};
        public static void main(String args[]){
            //This next line works
            System.out.println(new ChoGath().health);
            //This next line does not work
            System.out.println(listOfChampions[0].health);
        }
    }

There are more variables and whatnot but this is the basic problem.

ChoGath and Ahri are part of the group Champions and each has their own unique value for health. I want to be able to combine it all into an array for ease of grabbing values because I know where ChoGath (as an example) is in the array.

I get the error Cannot find symbol 'health' in Champions.Champion . I have gone and created the value in Champion and that fixes it (and also change it to class and then extends instead of implements) but then when I go to print the value is always 380.0 as it was the most recent edit to the value health in Champion.

I want it so that I can group all the "Champions" together under a single array (so they need to be the same object type ie: Champion, correct me if I'm wrong ) and access their individual values. I cannot seem to do this so I don't know if I need to use ArrayList (which I've never used) or something else entirely. Now I know I could fix this and put it all into a massive file but I am trying to use multiple files for organizational purposes as well as cleanliness. Thoughts on what to do?

Answer 1

You need to add getHealth() to your interface. That's what getters are for.

Also avoid the use of static variables. They tend to produce programming errors.

Answer 2

You have to use getters and setters in the interface to get this functionality, or use a base class instead of an interface for Champion , eg:

interface Champion
{
    public int getHealth();
    public void setHealth(int health);
}

Answer 3

You need to have health variable in your interface. That is similar to concept of Subclass and Superclass. You can't access the variables of subclass using a superclass type because all superclass are not subclass(vice versa is true).You can only access them if its defined in the superclass. If you use a health variable in interface it has to be final static. So its better you use a setter and getter method in the interface to get the value.

interface Champion { public int getHealth(); }

Now implement this method in the ChoGath and Ahri classes