Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Adrian Brock
Ok. I misundertood what you said. You are correct. The dependent's create() is invoked after the dependee's create() but the important point is that it is not (necessarily) in a usuable state. i.e. The dependee's start() may or may not have been invoked. On Mon, 2006-05-22 at 14:42 +0200, Ale

Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Alexey Loubyansky
This is how I understood slide 11 of 040-Microkernel.ppt. It's not clear that it's true only for mbeans from the same -service.xml. Create is called when all bean I depend on are “created” When a service's create method is called: - This gives an MBean an opportunity to check that required MBea

Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Adrian Brock
On Mon, 2006-05-22 at 14:20 +0200, Alexey Loubyansky wrote: > What I described is A in its start method referencing B. B in its create > method in fact can check the existence of A. > > According to our training material, in create a service can check that > the services it depends on exist. In

Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Alexey Loubyansky
What I described is A in its start method referencing B. B in its create method in fact can check the existence of A. According to our training material, in create a service can check that the services it depends on exist. In your case, B can check that A exists. Jerry Gauthier wrote: Right.

Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Jerry Gauthier
Right. The problem occurs when A.startService() assumes that any dependent services B have already been created. But Adrian points out that B should not reference A in createService(). It seems like this is the key contract - that services can't reference dependent services during create(). Exc

Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Alexey Loubyansky
Unless A also depends on B and, as a workaround to not supported cyclic dependencies, checks in its start method that B has been created and hopes that B will be started... any time soon. Adrian Brock wrote: The WIKI page says that B should not reference A in its createService() so what differ

Re: [JBoss-dev] Service start sequence

2006-05-22 Thread Adrian Brock
The WIKI page says that B should not reference A in its createService() so what difference does it make? "create() - the service should do any setup and __not reference another service__" On Fri, 2006-05-19 at 11:46 -0600, Jerry Gauthier wrote: > According to the wiki page at > http://wiki.jboss

RE: [JBoss-dev] Service start sequence

2006-05-19 Thread Brian Stansberry
This is because the unit of work is the individual deployment. The URLDeploymentScanner finds your -service.xml file, passes it to the MainDeployer, who passes it to the SARDeployer. SARDeployer tells ServiceController to instantiate and configure all mbeans declared in the file. Then it tells S

[JBoss-dev] Service start sequence

2006-05-19 Thread Jerry Gauthier
According to the wiki page at http://wiki.jboss.org/wiki/Wiki.jsp?page=ServiceLifecycle , the service lifecycle for two Services A and B is as follows. If Service B is dependent on Service A, the startup sequence is the following. ServiceA.createService(); ServiceB.createService(); ServiceA.start