How do you access a private integer (declared in a nested class) from a method within the starter class?

Question

I've seen lots of questions about accessing private methods, but none about accessing private integers, so I figured this was worth asking. Basically, I have my main class, RunnyStack, with a private nested class called Run. Inside Run, I initialized a private integer, length, and I'm trying to access this private int from a method inside RunnyStack.

I've already tried searching up this problem (for too long), and the answers I found don't work for me, because (per class instructions) I need to declare length as a private int inside Run. This means (from what I've tried) I cannot do 'Run hello = new Run();", because it says 'The constructor RunnyStack.Run() is undefined'. I also tried 'RunnyStack.Run len = new RunnyStack.Run();', but it just said 'The constructor RunnyStack.Run() is undefined'

    class RunnyStack<Base> {
private class Run {
    private Base base;
    private Run next;
    private int length;

    private Run(Base base, Run next) {
        this.base = base;
        this.next = next;
        this.length = 0;
    }
}

This code shows the creation of the nested private class, including the private integer length.

    public void push(Base base) {
    if(isEmpty()) {
        top = new Run(base, top);
    }
    else {
        if(base == top) {
            length += 1;
        }
    }
}

This code shows the method I'm trying to access length in

All I want to do is access length so that I can increase it whenever the if statement is fulfilled. Any help is appreciated, thanks!

Answer 1

Inside the Run class, create a getter method:

foo getFoo(){ // Cannot be private
    return this.foo;
}

Also: Setters

void setFoo(Foo f){ // Also cannot be private
    this.foo = f;
}

Answer 2

You need to implement a getter method - these are usually public methods which can access the private fields.

The format is usually

public field-type getFieldName () {
  return fieldname;
}

so for length it would be

public int getLength () {
    return length;
}