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https://issues.apache.org/jira/browse/BEANUTILS-402?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Gary D. Gregory closed BEANUTILS-402.
-------------------------------------
    Resolution: Fixed

> 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
>            Priority: Major
>             Fix For: 2.0.0
>
>          Time Spent: 20m
>  Remaining Estimate: 0h
>
> 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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