Hi,
I created ear file with about 6 war files. All war files are cocoon web applications
and thus have same WEB-INF/lib directories. The ear file has apx. 100MB due to
duplicity of libraries in WEB-INF/lib's. It seems reasonable to me to pull up those
duplicit libraries at ear level and share them among web applications.
But I'm stuck with the use of static ThreadLocal class fields in some cocoon classes.
Good example is CocoonComponentManager.environmentStack:
this static field is used in methods
- enterEnvironment()
- leaveEnvironment()
which are call on every request process by Cocoon.process() method:
process(Environment environment) {
try {
CocoonComponentManager.startProcessing(environment);
CocoonComponentManager.enterEnvironment(environment,
this.componentManager, this); // <- environmentStack.push
...
finally {
CocoonComponentManager.leaveEnvironment();
// -> environmentStack.pop
CocoonComponentManager.endProcessing(environment, key);
}
CocoonComponentManager.checkEnvironment(getLogger());
Providing that CocoonComponentManager class is located in WEB-INF/lib, we have no
problem, because every webapp gets its own class loader that creates its local
instance of static field. This field is then used only by proper webapplication and in
the threadsafe manner. But if we move CocoonComponentManager to ear level and share
this class among more than one web application, we break the contract, because only
one instance of this static field will be created for all web applications. When we
consider that one application can call other one, then we can see this not working,
because multiple web aplications will be writing the same instance of the static
field. The example is CocoonComponentManager.checkEnvironment() which throws exception
when environmentStack is not empty.
The problem can be even more visible in portlet environmnet (our environment in use),
when portlet container - webapp #1 is allowed to call portlets - webapp #2-#n)
parallelly in separate threads.
That's why the use of static ThredLocal class fields should be prohibited in all
cocoon component classes. There must be some alternative for it.
WDYT?
Call of CocoonComponentManager.checkEnvironment in Cocoon.process() is marked as
// TODO (CZ): This is only for testing - remove it later on
CocoonComponentManager.checkEnvironment(getLogger());
Isn't this the proper time to remove it? Or at least to have a possibility to disable
this check?
Thank you,
Michal
Attch: classes using the ThreadLocal static field:
src\blocks\scratchpad\java\org\apache\cocoon\ant\AntBuildGenerator.java
src\javaorg\apache\cocoon\components\CocoonComponentManager.java
src\blocks\portal\java\org\apache\cocoon\portal\serialization\IncludingHTMLSerializer.java
src\blocks\portal\java\org\apache\cocoon\portal\impl\PortletPortalManager.java
src\blocks\portal\java\org\apache\cocoon\portal\util\ReferenceFieldHandler.java
src\blocks\portal-fw\java\org\apache\cocoon\webapps\portal\context\SessionContextImpl.java
src\blocks\batik\java\org\apache\cocoon\components\url\SourceProtocolHandler.java
src\java\org\apache\cocoon\components\treeprocessor\variables\VariableResolverFactory.java
