commons-issues mailing list archives

Site index · List index
Message view « Date » · « Thread »
Top « Date » · « Thread »
From "Oliver Heger (JIRA)" <j...@apache.org>
Subject [jira] Commented: (CONFIGURATION-390) AbstractHierarchicalFileConfiguration is not thread safe
Date Mon, 28 Sep 2009 20:21:16 GMT

    [ https://issues.apache.org/jira/browse/CONFIGURATION-390?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=12760370#action_12760370
] 

Oliver Heger commented on CONFIGURATION-390:
--------------------------------------------

Ralph, your changes look good to me. I have the following questions/remarks:

* Can we be sure that the problem described in CONFIGURATION-344 does not pop up again? With
the lock used by the CombinedConfiguration and the locks used by child configurations there
are multiple locks involved which may be prone to dead lock under certain circumstances.
* I wonder whether SubnodeConfiguration.getRootNode() needs locking, too. Probably not, because
it is mainly called internally by methods that should already have the lock. But I am not
sure.

> AbstractHierarchicalFileConfiguration is not thread safe
> --------------------------------------------------------
>
>                 Key: CONFIGURATION-390
>                 URL: https://issues.apache.org/jira/browse/CONFIGURATION-390
>             Project: Commons Configuration
>          Issue Type: Bug
>          Components: File reloading
>    Affects Versions: 1.6
>            Reporter: Emmanuel Bourg
>             Fix For: 1.7
>
>         Attachments: commons-configuration-390.patch, configtest.tar.gz, TestSuite.txt
>
>
> AbstractHierarchicalFileConfiguration doesn't implement the same locking mechanism found
in AbstractFileConfiguration. The consequence is that getting a property while the configuration
is being reloaded by another thread can return an invalid result.
> This can be demonstrated by changing testDeadlockWithReload() in TestCombinedConfiguration
to use an XMLConfiguration instead of a PropertiesConfiguration.
> Here is a reduced test case:
> {code:java}
> public void testConcurrentGetAndReload() throws Exception
> {
>     //final FileConfiguration config = new PropertiesConfiguration("test.properties");
>     final FileConfiguration config = new XMLConfiguration("test.xml");
>     config.setReloadingStrategy(new FileAlwaysReloadingStrategy());
>     assertTrue("Property not found", config.getProperty("test.short") != null);
>     new Thread()
>     {
>         public void run()
>         {
>             for (int i = 0; i < 1000; i++)
>             {
>                 config.reload();
>             }
>         }
>     }.start();
>     
>     for (int i = 0; i < 1000; i++)
>     {
>         assertTrue("Property not found", config.getProperty("test.short") != null); //
failure here
>     }
> }
> {code}
> The test doesn't always fail. It does about 50% of the time.

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


Mime
View raw message