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https://issues.apache.org/jira/browse/LANG-520?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel
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Henri Yandell closed LANG-520.
------------------------------

    Resolution: Fixed

svn ci -m "Changing the hashCode() method to return toHashCode() per the 
request in LANG-520"
Sending        src/java/org/apache/commons/lang/builder/HashCodeBuilder.java
Sending        src/test/org/apache/commons/lang/builder/HashCodeBuilderTest.java
Transmitting file data ..
Committed revision 829285.

> HashCodeBuilder.hashCode() should return the same value as 
> HashCodeBuilder.toHashCode()
> ---------------------------------------------------------------------------------------
>
>                 Key: LANG-520
>                 URL: https://issues.apache.org/jira/browse/LANG-520
>             Project: Commons Lang
>          Issue Type: Improvement
>    Affects Versions: 2.4
>            Reporter: Paul Martin
>            Priority: Minor
>             Fix For: 3.0
>
>
> HashCodeBuilder's toHashCode() method must currently be used to generate the 
> calculated hash code value for an object.  However, this method name 
> ('toHashCode') is very similar to the standard 'hashCode()' method, which 
> will just return the (default) hash code of the HashCodeBuilder object 
> itself.  Since these names are so similar (and otherwise have the same 
> signature), they are easy to confuse.  If this happens, then the hashCode 
> used for an object will be that of the HashCodeBuilder, which then will 
> probably not be compatible with its 'equals' implementation.  This may result 
> in serious bugs (e.g. memory leaks when combined with ToStringBuilder - see 
> LANG-453).
> I suggest either:
> - Implement HashCodeBuilder.hashCode() to return the same value as 
> .toHashCode() (maybe with a logged warning), in which case it will not matter 
> if the wrong method is called.  This will still be compatible with 
> HashCodeBuilder's equals/hashCode contract, since equals is not implemented, 
> and should therefore be relatively backwards-compatible (though the hashCode 
> will now change as calls are made to HashCodeBuilder).
> - Throw an UnsupportedOperationException in hashCode().  This is more likely 
> to break existing code though.

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