On Aug 22, 2008, at 8:57 AM, Thorsten Scherler wrote:
On Fri, 2008-08-22 at 08:18 -0400, Vadim Gritsenko wrote:
On Aug 22, 2008, at 3:35 AM, Thorsten Scherler wrote:
How about:
} 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.
Exactly this thing I was trying to explain - it will not work because
instead of using top level request you are suggesting to use current
sub-request.
Sorry I am not really following. As understand you we cannot use
ObjectModelHelper.REQUEST_OBJECT since we cannot be sure that is not a
sub-request (a request for the exact same resource in a concurrent
situation).
Exactly.
If the lock is null for a HttpEnvironment.HTTP_REQUEST_OBJECT then we
are in CLI mode.
(patch quoted above does not have lock == null comparison anymore,
that's why it is dangerous for HTTP env)
In CLI ASAIK there is no concurrent situation meaning
the problem cannot occur. However since the issue is talking about
includes that may occur.
Yes. You can still use IncludeTransformer in CLI. So deadlock can
happen.
Having a typical call from the cli gives for the env.getObjectModel():
HashMap values:
[null,
[EMAIL PROTECTED],
link-collection=[],
[EMAIL PROTECTED],
null, null, null, null,
context
=
org
[EMAIL PROTECTED],
null, null, source-
resolver
=
org
[EMAIL PROTECTED],
org
.apache
.cocoon
.components
.CocoonComponentManager
[EMAIL PROTECTED], null,
null, null]
So which object you would suggest to lock?
You wrote "Suitable alternative would be to lock against top most
command line request."
To what you are referring with "top most command line request"?
That would be CommandLineRequest. Following HTTP environment analogy,
that would be CommandLineEnvironment.CLI_REQUEST_OBJECT.
Vadim
salu2
Take a look at EnvironmentWrapper (which is used e.g. in
SitemapSource):
// create new object model and replace the request object
Map oldObjectModel = env.getObjectModel();
if (oldObjectModel instanceof HashMap) {
this.objectModel = (Map)
((HashMap)oldObjectModel).clone();
} else {
this.objectModel = new HashMap(oldObjectModel.size()*2);
Iterator entries = oldObjectModel.entrySet().iterator();
Map.Entry entry;
while (entries.hasNext()) {
entry = (Map.Entry)entries.next();
this.objectModel.put(entry.getKey(),
entry.getValue());
}
}
this.request = new
RequestWrapper(ObjectModelHelper.getRequest(oldObjectModel),
requestURI,
queryString,
this,
rawMode);
this.objectModel.put(ObjectModelHelper.REQUEST_OBJECT,
this.request);
Vadim
--
Thorsten Scherler
thorsten.at.apache.org
Open Source Java consulting, training and
solutions
