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https://issues.apache.org/jira/browse/BEANUTILS-402?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=15449094#comment-15449094
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Hans-Peter Störr commented on BEANUTILS-402:
--------------------------------------------
Why don't you just fix it with making
org.apache.commons.beanutils.WeakFastHashMap.map volatile? That's easy and
solves the problem. I guess hardly anyone uses Java versions less than Java 5.
> Double-Checked Locking anti pattern in WeakFastHashMap
> ------------------------------------------------------
>
> Key: BEANUTILS-402
> URL: https://issues.apache.org/jira/browse/BEANUTILS-402
> Project: Commons BeanUtils
> Issue Type: Bug
> Components: Bean / Property Utils, ConvertUtils & Converters, Locale
> BeanUtils / Converters
> Affects Versions: 1.8.3
> Environment: Win XP, but doesn't matter
> Reporter: Volker Malzahn
> Fix For: 2.0
>
>
> The implementation of WeakFastHashMap has the flaw of implementing the
> Double-Checked Locking anti pattern (see JavaDoc of that class). As described
> in the JavaDoc "This class is not cross-platform.". In
> https://issues.apache.org/jira/browse/BEANUTILS-318 and
> https://issues.apache.org/jira/browse/BEANUTILS-373 this was solved for
> MethodUtils (usage of WeakFastHashMap). But following classes still use
> WeakFastHashMap for a cache: BeanUtils, ConvertUtilsBean, PropertyUtilsBean,
> LocaleConvertUtilsBean.
> I would suggest to make WeakFastHashMap deprecated and to change every usage
> of that class inside the commons-beanutils classes to a synchronized normal
> WeakHashMap like done (as the second step) in
> https://issues.apache.org/jira/browse/BEANUTILS-318. Otherwise strange things
> may happen in unusual plattforms/environments. An alternative could be to use
> "volatile" inside WeakFastHashMap which would fix it for Java 5 and higher
> (see http://en.wikipedia.org/wiki/Double-checked_locking or
> http://www.cs.umd.edu/~pugh/java/memoryModel/jsr-133-faq.html#volatile).
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