为什么 IntelliJ 找不到我覆盖的 hasNext() 函数？

Question

I think this should be an easy problem, but I just can't solve it. Actually,I'm learning stack with iteration, when I tried to implement interface Iterable, IDE kept warning me for not implementing the method hasNext()

Here's my code:

import java.util.Iterator;

public class ResizingArrayStack<Item> implements Iterator<Item>
{
    private Item[] array = (Item[]) new Object[1]; //stores the elements
    private int size = 0;                          //number of the elements

    /*
    Codes that doesn't matter
    */

    //implement iterator()
    public Iterator<Item> iterator()
    {
        return new ReverseArrayIterator();
    }

    private class ReverseArrayIterator implements Iterator<Item>
    {
        private int i = size();

        //I ALREADY IMPLEMENTED IT!
        @Override
        public boolean hasNext()
        {
            return i > 0;
        }
        
        @Override
        public Item next()
        {
            return a[--i];
        }
    }
}

And here's what IDE shows:

Class 'ResizingArrayStack' must either be declared abstract or implement abstract method 'hasNext()' in 'Iterator'

I'll really appreciate it if you guys can answer this for me!

Answer 1

What I wrote in the inner class was correct, the problem is that, I should have been more strict when define class ResizingArrayStack . It should implements Iterable instead of Iterator