Carsten Ziegeler wrote:
Sylvain Wallez wrote:
Spotted the problems, which are actually twofold in the TreeProcessor:I think we have the second problem in Cocoon since our first version :(
- sitemap modification date is checked to be before or equal to the date when the treeprocessor was built, meaning continuous rebuild if the sitemap date is in the future
- treeprocessor disposal (and hence its component manager) occurs as soon as change is detected, even if some other request (either in another thread or through a "cocoon:") currently use that treeprocessor, leading to the IllegalStateExceptions
The first problem is easy to solve, but the second one is more tricky. My current thinking about it is to add a concurrent requests counter and disposal flag. When a sitemap change is detected the flag is set to true. The treeprocessor will be disposed if the disposal flag is true _and_ the concurrent requests counter is zero.
I always thought about adding a counter for the concurrent requests
in a tree processor, but always forget about it :( Regarding
performance: is this a problem as the counter has to be synchronized?
I was just looking in the VM spec if a increment operation on an integer is atomic or not. My opinion it has to be in the case of class members as the increment is surrounded by getfield/putfield instructions.
But the overhead should be minimal, as only the increment/decrement operation have to be synchronized.
Sylvain, currently working on the fix.
-- Sylvain Wallez Anyware Technologies http://www.apache.org/~sylvain http://www.anyware-tech.com { XML, Java, Cocoon, OpenSource }*{ Training, Consulting, Projects }
