Question

I am working on a project in which I need to add a ton of objects to an ArrayList and then call specific functions in them later on. I have this part down but in my program I need to access specific instances from the ArrayList with only the parameter of the class I am looking for.
For example:

public class Manager {
    public static ArrayList<O> loadedHacks = new ArrayList<O>();
    public void initOs(){
        loadedHacks.add(new O());
    }
}

public class O {
    public boolean enabled = false;
    public void onEnable(){}
}

public class A extends O{
}

Then later I want to do something like this:

if(Helper.get(A.class).enabled){}

Answer 1

It isn’t exactly clear from your question what the actual problem is that you’re trying to solve, but if I understand correctly, what you’re trying to do is say: “object X could be of some subclass of class A. If it’s subclass B, then I want to call B.method(), which isn’t defined on A”.

In which, case you can do something like this:

if (object instanceof SpecificSubclass) {
  SpecificSubclass specificObject = (SpecificSubclass) object;
  specificObject.specificMethod();
}

EDIT: from your comment, it seems the functionality you’re looking for is slightly different. If you have as a parameter a Class, then to see if a particular object is in effect an instance of that class, use the Class.isAssignableFrom() method.