You are viewing a plain text version of this content. The canonical link for it is here.
Posted to dev@sling.apache.org by "Justin Edelson (JIRA)" <ji...@apache.org> on 2017/05/12 10:54:04 UTC
[jira] [Resolved] (SLING-6852) A question about reliability of
keeping non DS tracked references
[ https://issues.apache.org/jira/browse/SLING-6852?page=com.atlassian.jira.plugin.system.issuetabpanels:all-tabpanel ]
Justin Edelson resolved SLING-6852.
-----------------------------------
Resolution: Information Provided
> A question about reliability of keeping non DS tracked references
> -----------------------------------------------------------------
>
> Key: SLING-6852
> URL: https://issues.apache.org/jira/browse/SLING-6852
> Project: Sling
> Issue Type: Task
> Components: Best practices
> Affects Versions: Sling Models Impl 1.2.0
> Reporter: Dominik Smogór
> Priority: Minor
>
> It's a generic best practice question but illustrated on an example within sling models.
> We have 2 kind osgi services being in parent - child
> 1. a factory service that programmatically registers number listener services
> 2. the listener services.
> The listener services are called asynchronously (usually in a white board manner) by some 3rd party components.
> Now, the listener services implementations are keeping a simple object references to the parent service. Osgi is not aware of this link and is not tracking it in any way.
> An example of such a relation is here http://grepcode.com/file/repo1.maven.org/maven2/org.apache.sling/org.apache.sling.models.impl/1.2.0/org/apache/sling/models/impl/ModelAdapterFactory.java#900:
> with the ModelAdapterFactory creating instances of ModelPackageBundleListener which self register themselves with BundleTracker.
> No the question is: what guarantee do we have that the child services will never use defunct instances of parent objects after they have been deactivated by OSGI (for whatever reason)?
> Isn't it a potential for race conditions (that partner is used frequently throughout sling code base) during after related to bundle / component restarts?
> (disclaimer: I've used the highest sling models version that's there on grepcode)
--
This message was sent by Atlassian JIRA
(v6.3.15#6346)