HashMap entry lazy initialization in multithreaded enviroment? - 未名空间MITBBS历史存档

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HashMap entry lazy initialization in multithreaded enviroment?

HashMap entry lazy initialization in multithreaded enviroment?# Java - 爪哇娇娃

d*i2014-01-19 08:01

1 楼

【以下文字转载自 Immigration 讨论区】
发信人: daofei (摸鱼大侠), 信区: Immigration
标题: 请教个F1 转学的问题
发信站: BBS 未名空间站 (Mon Feb 8 20:33:55 2010, 美东)
F1 的时候申请了亲属移民，还能转学去别的学校么，身份会有问题吗？

l*n2014-01-19 08:01

2 楼

看到很多作品，都是在国内DIY网站上见过哦，哈哈哈，看来手工爱好者，喜欢逛的地
方都差不多啊，哈哈

m*a2014-01-19 08:01

3 楼

G*32014-01-19 08:01

4 楼

I have a problem. The entry in a hashmap has a big cost to create. So I want
to do lazy initialization. But it is in multithreaded enviroment. So I
resolve the issues like doubled checked locking and etc.

b*k2014-01-19 08:01

5 楼

co-ask

B*n2014-01-19 08:01

6 楼

love it!

w*z2014-01-19 08:01

7 楼

take a look at guava cache.

want

【在 G****3 的大作中提到】

: I have a problem. The entry in a hashmap has a big cost to create. So I want
: to do lazy initialization. But it is in multithreaded enviroment. So I
: resolve the issues like doubled checked locking and etc.

g*g2014-01-19 08:01

8 楼

ConcurrentHashMap.

want

【在 G****3 的大作中提到】

G*32014-01-19 08:01

9 楼

I read the code of ConcurrentHashMap. It does work. The get(key) doesn't use
lock for most cases. But it uses volatile to guarantee it can always get
the latest value. Very sophisticated code.
Thanks for the reply!