Vector.Itr 该类源码中的 synchronized 是为了？

c4f36e5766583218 · 2019-04-09T00:21:57Z

不知道什么关键字触发 403 Forbidden nginx 了，我一段段打 java.util.Vector.Itr 源码里面好几处，这样写的作用是？ synchronized (Vector.this) {

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不知道什么关键字触发 403 Forbidden nginx 了，我一段段打

java.util.Vector.Itr 源码里面好几处，这样写的作用是？

synchronized (Vector.this) {

Supplement 1 · Apr 9, 2019

1.8的java.util.Vector#readObject(ObjectInputStream) 源码里没看到defaultReadObject也没读capacityIncrement，反序列化会丢capacityIncrement值吧？

Supplement 2 · Apr 10, 2019

三: SynchronizedList和Vector的区别？只回答sync相关的区别即可（比如Collections#synchronizedList(ArrayList)与Vector）

Supplement 3 · Apr 10, 2019

#SynchronizedList和Vector的区别，网上搜到一个但没没明白要点
#老是被ban，不知道触发了什么关键字，浏览器Console执行下
["h","t","t","p","s",":","/","/","w","w","w",".","h","o","l","l","i","s","c","h","u","a","n","g",".","c","o","m","/","a","r","c","h","i","v","e","s","/","4","9","8"].join("/")

itr

vector

源码

Java

4 replies • 2019-04-11 08:43:08 +08:00

jsshaojinjie

Apr 9, 2019

是为了线程安全

c4f36e5766583218

Apr 10, 2019

fix: 打错了，是.join("")

@jsshaojinjie #1

* 哦，我搞错了，问题 1 应该是这样: 这样写是保证 Vector.Itr 创建的实例是线程安全的，比如 Vector.Itr#remove()方法内部```remove(lastRet);```不会并发导致数据多删，（线程安全并不是说不会报错，像 remove 的话还是可能 ArrayIndexOutOfBoundsException 的）
* 那问题 3 应该就是说 SynchronizedList 返回的 Iterator 并不一定是线程安全的

updated: 那看下问题 2 吧。

jsshaojinjie

Apr 11, 2019

@c4f36e5766583218 哪个是问题 2

c4f36e5766583218

Apr 11, 2019

@jsshaojinjie #3 问题 2=第 1 条附言