Java | Leetcode Java题解之第284题窥视迭代器

题目：

题解：

class PeekingIterator<E> implements Iterator<E> {private Iterator<E> iterator;private E nextElement;public PeekingIterator(Iterator<E> iterator) {this.iterator = iterator;nextElement = iterator.next();}public E peek() {return nextElement;}@Overridepublic E next() {E ret = nextElement;nextElement = iterator.hasNext() ? iterator.next() : null;return ret;}@Overridepublic boolean hasNext() {return nextElement != null;}
}