AbstractList.equals（Object o）

做java2年多，没什么长进，在未来1年要研究一般JDK源码，每天记载一点：

AbstractList.equals（Object o）的实现源码写的实在是太简练、精辟了

public boolean equals(Object o) {if (o == this)    return true;if (!(o instanceof List))    return false;ListIterator<E> e1 = listIterator();ListIterator e2 = ((List) o).listIterator();while(e1.hasNext() && e2.hasNext()) {    E o1 = e1.next();    Object o2 = e2.next();    if (!(o1==null ? o2==null : o1.equals(o2)))return false;}return !(e1.hasNext() || e2.hasNext());    }

Iterrator实现源码

private class Itr implements Iterator<E> {/** * Index of element to be returned by subsequent call to next. */int cursor = 0;/** * Index of element returned by most recent call to next or * previous.  Reset to -1 if this element is deleted by a call * to remove. */int lastRet = -1;/** * The modCount value that the iterator believes that the backing * List should have.  If this expectation is violated, the iterator * has detected concurrent modification. */int expectedModCount = modCount;public boolean hasNext() {            return cursor != size();}public E next() {            checkForComodification();    try {E next = get(cursor);lastRet = cursor++;return next;    } catch (IndexOutOfBoundsException e) {checkForComodification();throw new NoSuchElementException();    }}public void remove() {//验证当前迭代元素是否已经remove    if (lastRet == -1)throw new IllegalStateException();            checkForComodification();    try {    //remove当前迭代的元素AbstractList.this.remove(lastRet);//索引位置-1if (lastRet < cursor)    cursor--;//修改移除元素标志lastRet = -1;//遍历时 集合添加修改标志？expectedModCount = modCount;    } catch (IndexOutOfBoundsException e) {throw new ConcurrentModificationException();    }}final void checkForComodification() {    if (modCount != expectedModCount)throw new ConcurrentModificationException();}    }