You are viewing a plain text version of this content. The canonical link for it is here.
Posted to log4j-dev@logging.apache.org by "Remko Popma (JIRA)" <ji...@apache.org> on 2013/03/03 03:01:13 UTC
[jira] [Comment Edited] (LOG4J2-169) LogManager.getLogger doesn't
work
[ https://issues.apache.org/jira/browse/LOG4J2-169?page=com.atlassian.jira.plugin.system.issuetabpanels:comment-tabpanel&focusedCommentId=13591576#comment-13591576 ]
Remko Popma edited comment on LOG4J2-169 at 3/3/13 2:00 AM:
------------------------------------------------------------
You are right, I missed the "volatile" declaration.
Still, the "static singleton" solution proposed in both the articles (in yours it's under "Making it work for static singletons") looks a lot simpler:
(and it will be faster because it doesn't even have the volatile memory barrier).
private static List<ConfigurationFactory> factories = createFactories(); // no need to make this volatile
public static List<ConfigurationFactory> getInstance() { return factories; }
private static List<ConfigurationFactory> createFactories() { // no need for null checking or synchronization here
List<ConfigurationFactory> list = new ArrayList<ConfigurationFactory>();
....
return Collections.unmodifiableList(list);
}
was (Author: remkop@yahoo.com):
You are right, I missed the "volatile" declaration.
Still, the "static singleton" solution proposed in both the articles (in yours it's under "Making it work for static singletons") looks a lot simpler:
(and it will be faster because it doesn't even have the volatile memory barrier).
private static List<ConfigurationFactory> factories = createFactories(); // no need to make this volatile
public static List<ConfigurationFactory> getInstance() { return factories; } // first time this is called, the "factories" field is initialized
private static List<ConfigurationFactory> createFactories() { // no need for null checking or synchronization here
List<ConfigurationFactory> list = new ArrayList<ConfigurationFactory>();
....
return Collections.unmodifiableList(list);
}
> LogManager.getLogger doesn't work
> ---------------------------------
>
> Key: LOG4J2-169
> URL: https://issues.apache.org/jira/browse/LOG4J2-169
> Project: Log4j 2
> Issue Type: Bug
> Components: Core
> Affects Versions: 2.0-beta4
> Reporter: Jed Wesley-Smith
> Priority: Critical
> Labels: thread-safety
>
> We randomly get the following:
> java.util.ConcurrentModificationException
> at org.apache.logging.log4j.core.config.ConfigurationFactory$Factory.getConfiguration(ConfigurationFactory.java:377)
> at org.apache.logging.log4j.core.config.ConfigurationFactory$Factory.getConfiguration(ConfigurationFactory.java:361)
> at org.apache.logging.log4j.core.LoggerContext.reconfigure(LoggerContext.java:266)
> at org.apache.logging.log4j.core.LoggerContext.start(LoggerContext.java:134)
> at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:75)
> at org.apache.logging.log4j.core.impl.Log4jContextFactory.getContext(Log4jContextFactory.java:30)
> at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:165)
> at org.apache.logging.log4j.LogManager.getLogger(LogManager.java:174)
> at …
> factories is defined as:
> private static List<ConfigurationFactory> factories = new ArrayList<ConfigurationFactory>();
> The simple fix is to use a java.util.concurrent.CopyOnWriteArrayList:
> private static final List<ConfigurationFactory> factories = new CopyOnWriteArrayList<ConfigurationFactory>();
> https://svn.apache.org/repos/asf/logging/log4j/log4j2/trunk/core/src/main/java/org/apache/logging/log4j/core/config/ConfigurationFactory.java
--
This message is automatically generated by JIRA.
If you think it was sent incorrectly, please contact your JIRA administrators
For more information on JIRA, see: http://www.atlassian.com/software/jira
---------------------------------------------------------------------
To unsubscribe, e-mail: log4j-dev-unsubscribe@logging.apache.org
For additional commands, e-mail: log4j-dev-help@logging.apache.org