Abstract class with final uninitialized field

I was wondering if the below code makes any sense, since the compiler warns that "the blank final field objects may not have been initialized". Is there a better way of doing this?

public abstract Test {
  protected final ArrayList<Object> objects;
}

public TestSubA extends Test {

  public TestSubA() {
    objects = new ArrayList<Objects>(20);
    // Other stuff
  }
}

public TestSubB extends Test {

  public TestSubB() {
    objects = new ArrayList<Objects>(100);
    // Other stuff
  }
}

I would make the field final and force the constructors to pass the value up:

public abstract class Test {
  private final ArrayList<Object> objects;

  protected ArrayList<Object> getObjects() {
    return objects;
  }

  protected Test(ArrayList<Object> objects) {
    this.objects = objects;
  }
}

public class TestSubA extends Test {

  public TestSubA() {
    super(new ArrayList<Object>(20));
    // Other stuff
  }
}

public class TestSubB extends Test {

  public TestSubB() {
    super(new ArrayList<Object>(100));
    // Other stuff
  }
}

The problem with initializing the final parameters directly in the constructor of the sub-classes is that you need to do it all in one line since super() must be the first statement of the constructor. So instead, I prefer to make the constructor non-public and make a static build method like this:

public abstract class Test {
  protected final ArrayList<Object> objects;

  protected Test(ArrayList<Object> objects) {
    this.objects = objects;
  }
}

public class TestSubA extends Test {
  public static TestSubA build() {
    ArrayList<Object> objects = new ArrayList<Object>(20);
    objects.put(...);
    // Other stuff
    return new TestSubA(objects);
  }

  private TestSubA(ArrayList<Object> objects) {
    super(objects);
  }
}

Instantiate the objects in the abstract class constructor and just pass the difference to the that constructor.

Abstract class with final uninitialized field

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