迭代器模式

public interface Iterator {

    boolean hasNext();

    Object next();

}

import java.util.ArrayList;


public class IteratorImpl<T> implements Iterator {

    ArrayList list = new ArrayList<T>();
    int index = 0;

    @Override

    public boolean hasNext() {
        int len = list.size();
        if (index < len) {
            return true;
        } else {
            return false;
        }
    }

    @Override
    public T next() {
        return (T)list.get(index++);
    }

}