Return-Path: 
 <issues-return-46123-apmail-commons-issues-archive=commons.apache.org@commons.apache.org>
X-Original-To: apmail-commons-issues-archive@minotaur.apache.org
Delivered-To: apmail-commons-issues-archive@minotaur.apache.org
Received: from mail.apache.org (hermes.apache.org [140.211.11.3])
	by minotaur.apache.org (Postfix) with SMTP id 5009D17629
	for <apmail-commons-issues-archive@minotaur.apache.org>;
 Thu,  5 Feb 2015 22:15:35 +0000 (UTC)
Received: (qmail 92195 invoked by uid 500); 5 Feb 2015 22:15:35 -0000
Delivered-To: apmail-commons-issues-archive@commons.apache.org
Received: (qmail 92097 invoked by uid 500); 5 Feb 2015 22:15:35 -0000
Mailing-List: contact issues-help@commons.apache.org; run by ezmlm
Precedence: bulk
List-Help: <mailto:issues-help@commons.apache.org>
List-Unsubscribe: <mailto:issues-unsubscribe@commons.apache.org>
List-Post: <mailto:issues@commons.apache.org>
List-Id: <issues.commons.apache.org>
Reply-To: issues@commons.apache.org
Delivered-To: mailing list issues@commons.apache.org
Received: (qmail 92076 invoked by uid 99); 5 Feb 2015 22:15:35 -0000
Received: from arcas.apache.org (HELO arcas.apache.org) (140.211.11.28)
    by apache.org (qpsmtpd/0.29) with ESMTP; Thu, 05 Feb 2015 22:15:35 +0000
Date: Thu, 5 Feb 2015 22:15:34 +0000 (UTC)
From: "Thomas Neidhart (JIRA)" <jira@apache.org>
To: issues@commons.apache.org
Message-ID: <JIRA.12770532.1422402851000.272146.1423174534955@Atlassian.JIRA>
In-Reply-To: <JIRA.12770532.1422402851000@Atlassian.JIRA>
References: <JIRA.12770532.1422402851000@Atlassian.JIRA>
 <JIRA.12770532.1422402851544@arcas>
Subject: [jira] [Commented] (POOL-284) "Returned object not currently part
 of this pool" when using mutable objects
MIME-Version: 1.0
Content-Type: text/plain; charset=utf-8
Content-Transfer-Encoding: 7bit
X-JIRA-FingerPrint: 30527f35849b9dde25b450d4833f0394


    [ https://issues.apache.org/jira/browse/POOL-284?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=14308096#comment-14308096 ] 

Thomas Neidhart commented on POOL-284:
--------------------------------------

I have found a paper about performance regression testing. Interestingly, they evaluated both, GenericObjectPool and StaticBucketMap:

http://mp.binaervarianz.de/issta2014.pdf

The test code is available here: https://github.com/michaelpradel/ConTeGe/tree/SpeedGun

> "Returned object not currently part of this pool" when using mutable objects
> ----------------------------------------------------------------------------
>
>                 Key: POOL-284
>                 URL: https://issues.apache.org/jira/browse/POOL-284
>             Project: Commons Pool
>          Issue Type: Bug
>    Affects Versions: 2.2
>            Reporter: Valentin Mayamsin
>
> I'm using pool to reuse expensive Sets (storing millions of items). Here is a test which fails:
> {code}
>         GenericObjectPoolConfig config = new GenericObjectPoolConfig ();
>         GenericObjectPool<Set> aPool = new GenericObjectPool<> ( new BasePooledObjectFactory<Set> ()
>         {
>             @Override
>             public Set create () throws Exception
>             {
>                 return new HashSet();
>             }
>             @Override
>             public PooledObject<Set> wrap ( Set o )
>             {
>                 return new DefaultPooledObject<> ( o );
>             }
>             @Override
>             public void passivateObject ( PooledObject<Set> p ) throws Exception
>             {
>                 p.getObject ().clear ();
>                 super.passivateObject ( p );
>             }
>         }, config );
>         Set set = aPool.borrowObject ();
>         set.add ( new Object () );
>         
>         aPool.returnObject ( set );
> {code}
> This is because GenericObjectPool uses a HashMap<Object, PooledObject> to correlate objects and state. HashMap stores objects correlated to their hashCode. So in case object's state change then hashCode will change, thus Map will fail to correlate this object since it stores old hashCode



--
This message was sent by Atlassian JIRA
(v6.3.4#6332)