[jira] Commented: (IVY-791) Memory leak in ModuleRevisionId.java

["Archie Cobbs (JIRA)" <ji...@apache.org>]

    [ https://issues.apache.org/jira/browse/IVY-791?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12585737#action_12585737 ] 

Archie Cobbs commented on IVY-791:
----------------------------------

Sorry, I said that backwards speaking of key vs. value.

It's the strong reference to the _value_ that causes the weak reference to the _key_ to never be cleared.

The fix is to wrap the values (not the keys) in WeakReferences.


> Memory leak in ModuleRevisionId.java
> ------------------------------------
>
>                 Key: IVY-791
>                 URL: https://issues.apache.org/jira/browse/IVY-791
>             Project: Ivy
>          Issue Type: Bug
>          Components: Core
>    Affects Versions: 2.0.0-beta-2
>            Reporter: Archie Cobbs
>
> In ModuleRevisionId.java an attempt is made to create a "canconical instance" cache like {{String.intern()}} using this static field:
> {noformat}
> private static final Map/*<ModuleRevisionId, ModuleRevisionId>*/ CACHE = new WeakHashMap();
> {noformat}
> This doesn't work: each entry is both a key and a value, so the strong reference to the key will never allow the weak reference to the value to be the only remaining reference, and so entries will never be dropped.
> You have to wrap the keys in a WeakReference.
> See [Classpath's implementation of String.intern()|http://cvs.savannah.gnu.org/viewvc/classpath/vm/reference/java/lang/VMString.java?root=classpath&view=markup] for an example.

-- 
This message is automatically generated by JIRA.
-
You can reply to this email to add a comment to the issue online.