ArrayList实现了ListIterator接口
这个接口在Iterator接口的基础上,可以查找前驱和后继节点.还能添加和修改.
ArrayList的ListIterator实现.
- public interface ListIterator<E> extends Iterator<E> {
- boolean hasNext();
- E next();
- boolean hasPrevious();
- E previous();
- int nextIndex();
- int previousIndex();
- void remove();
- void set(E e);
- void add(E e);
- }
这个接口在Iterator接口的基础上,可以查找前驱和后继节点.还能添加和修改.
ArrayList的ListIterator实现.
- private class ListItr extends Itr implements ListIterator<E> {
- ListItr(int index) {
- super();
- cursor = index;
- }
- public boolean hasPrevious() {
- return cursor != 0;
- }
- public int nextIndex() {
- return cursor;
- }
- public int previousIndex() {
- return cursor - 1;
- }
- @SuppressWarnings("unchecked")
- public E previous() {
- checkForComodification();
- int i = cursor - 1;
- if (i < 0)
- throw new NoSuchElementException();
- Object[] elementData = ArrayList.this.elementData;
- if (i >= elementData.length)
- throw new ConcurrentModificationException();
- cursor = i;
- return (E) elementData[lastRet = i];
- }
- public void set(E e) {
- if (lastRet < 0)
- throw new IllegalStateException();
- checkForComodification();
- try {
- ArrayList.this.set(lastRet, e);
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
- }
- public void add(E e) {
- checkForComodification();
- try {
- int i = cursor;
- ArrayList.this.add(i, e);
- cursor = i + 1;
- lastRet = -1;
- expectedModCount = modCount;
- } catch (IndexOutOfBoundsException ex) {
- throw new ConcurrentModificationException();
- }
- }
- }
来自 “ ITPUB博客 ” ，链接：https://blog.itpub.net/29254281/viewspace-2121743/ ，如需转载，请注明出处，否则将追究法律责任。
下一篇：
内部类总结
请登录后发表评论
登录
全部评论
