On Thu, 2008-08-21 at 19:40 -0400, Vadim Gritsenko wrote:
> On Aug 21, 2008, at 8:18 AM, Thorsten Scherler wrote:
>
> > still updating forrest to use cocoon-2.1.x and I found a problem in
> > the
> > AbstractCachingProcessingPipeline.
> >
> > I am not sure whether someone is using the cocoon cli ATM. Forrest is
> > based around this component.
> >
> > https://issues.apache.org/jira/browse/FOR-955?focusedCommentId=12624340
> > #action_12624340
> >
> > I found that in
> > org
> > .apache
> > .cocoon.components.pipeline.impl.AbstractCachingProcessingPipeline
> > line 245
> > Object lock =
> > env.getObjectModel().get(HttpEnvironment.HTTP_REQUEST_OBJECT);
> > the lock is null which causes the NPE in the end.
> >
> > I changed it the following way:
> > Object lock =
> > env.getObjectModel().get(HttpEnvironment.HTTP_REQUEST_OBJECT);
> > + if (null==lock){
> > + lock =
> > env.getObjectModel().get(ObjectModelHelper.REQUEST_OBJECT);
> > + }
> > try {
> >
> > and now it is working as before.
> >
> > Can somebody verify that it is a bug? Should I commit the patch?
>
> It is a bug, but with proposed change you can get a deadlock under
> some conditions (IIRC, when using parallels inclusion in the sitemap
> which ultimately pull from the same pipeline). The idea behind that
> lock is to synchronize on the main request (top most request), and not
> on any of sub-request object created during aggregation. Suitable
> alternative would be to lock against top most command line request.
How about:
Index:
src/java/org/apache/cocoon/components/pipeline/impl/AbstractCachingProcessingPipeline.java
===================================================================
---
src/java/org/apache/cocoon/components/pipeline/impl/AbstractCachingProcessingPipeline.java
(revision 681296)
+++
src/java/org/apache/cocoon/components/pipeline/impl/AbstractCachingProcessingPipeline.java
(working copy)
@@ -36,6 +36,7 @@
import org.apache.cocoon.caching.ComponentCacheKey;
import org.apache.cocoon.caching.PipelineCacheKey;
import org.apache.cocoon.environment.Environment;
+import org.apache.cocoon.environment.ObjectModelHelper;
import org.apache.cocoon.environment.http.HttpEnvironment;
import org.apache.cocoon.transformation.Transformer;
import org.apache.cocoon.util.HashUtil;
@@ -242,7 +243,7 @@
getLogger().debug("Lock EXISTS: '" + lockKey +
"'");
}
} else {
- Object lock =
env.getObjectModel().get(HttpEnvironment.HTTP_REQUEST_OBJECT);
+ Object lock =
env.getObjectModel().get(ObjectModelHelper.REQUEST_OBJECT);
try {
transientStore.store(lockKey, lock);
} catch (IOException e) {
This way we always lock the same object.
Thanks for the feedback Vadim.
salu2
>
> Vadim
--
Thorsten Scherler thorsten.at.apache.org
Open Source Java consulting, training and solutions
