Java code


    import java.util.Iterator;
    import java.util.NoSuchElementException;

    public abstract class AbstractIterator<T> implements Iterator<T> {

    T next = nextElement();

    public boolean hasNext() {
    return next != null;
    }

    public T next() {
    if (next == null) {
    throw new NoSuchElementException();
    }
    T result = next;
    next = nextElement();
    return result;
    }

    public void remove() {
    throw new UnsupportedOperationException();
    }

    protected abstract T nextElement();

    private static Iterator<Character> test(final String s) {
    return new AbstractIterator<Character>() {

    private int cursor = 0;

    protected Character nextElement() {
    return cursor == s.length() ? null : s.charAt(cursor++);
    }
    };
    }

    public static void main(String[] args) {
    for (Iterator<Character> i = test("OPS"); i.hasNext();) {
    System.out.print(i.next());
    }
    }
    }





问题：输出结果是什么？

Java code


    import java.util.Iterator;
    import java.util.NoSuchElementException;

    public abstract class AbstractIterator<T> implements Iterator<T> {

    T next = nextElement();

    public boolean hasNext() {
    return next != null;
    }

    public T next() {
    if (next == null) {
    throw new NoSuchElementException();
    }
    T result = next;
    next = nextElement();
    return result;
    }

    public void remove() {
    throw new UnsupportedOperationException();
    }

    protected abstract T nextElement();

    private static Iterator<Character> test(final String s) {
    return new AbstractIterator<Character>() {

    private int cursor = 0;

    protected Character nextElement() {
    return cursor == s.length() ? null : s.charAt(cursor++);
    }
    };
    }

    public static void main(String[] args) {
    for (Iterator<Character> i = test("OPS"); i.hasNext();) {
    System.out.print(i.next());
    }
    }
    }





问题：输出结果是什么？