On Friday, January 24, 2003, at 03:23 PM, Matt Munz wrote:
this one didn't make it either...In all the mbeans I have written and seen in jboss, aside from egregious bugs, if setting an attribute doesn't have an immediate effect, it does have the desired effect if you run through the service lifecycle (usually stop, start, occasionally stop, destroy, create, start). My view is that mbeans in jboss can take advantage of the service lifecycle. If you don't want to, make all your attribute changes have their effects immediately. All our mbeans are pretty much jboss specific and most heavily use the service lifecycle. They just won't run without it. I still think it is a really convenient extension to vanilla jmx and don't see why we should replace it.
-----Original Message-----
From: Matt Munz
Sent: Fri 1/24/2003 12:18 PM
To: [EMAIL PROTECTED]
Cc:
Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master Configuration Service
David,
If you will, take a step back with me. Think JMX and not JBoss-JMX. You are writing a tool to do generic operations on MBeans. This is the purpose of JMX in the first place. Your tool encounters a RW attribute. What assumptions can be made, reasonably?
Here are my assumptions:
1. get the value of the attribute and store it in an object. Do not modify the object. Set the value of the attribute to the object. No error will occur.
2. set the attribute to a given value that is not equivalent to the current value. The behavior / state of the MBean will change in a meaningful way.
Does the JMX spec enforce these? Perhaps not. Is it nevertheless reasonable to expect this behavior? I think so. Neither of these assumptions are upheld, however, in the current use of MBeans in > JBoss.
I realize that re-writing mbeans might cause pain for the project. I'm not suggesting that it should even be done, necessarily, at least not right away. I am, however, trying to reconcile the notion of a RW attribute where writing the value has no effect. Can this be explained simply?
BTW, I don't see how the lifecycle is related to this particular issue. Perhaps you could explain this in more depth?
david jencks
- Matt
-----Original Message-----
From: David Jencks [mailto:[EMAIL PROTECTED]]
Sent: Fri 1/24/2003 11:44 AM
To: [EMAIL PROTECTED]
Cc:
Subject: Re: [JBoss-dev] [ jboss-Change Notes-672538 ] Master Configuration Service
On Friday, January 24, 2003, at 11:07 AM, Matt Munz wrote:
> Sacha,
>
> I follow you fine. The RW attributes you describe should be RO.
> Another mechanism should be used to designate a default value. This
> (mis)use of the MBean interface results in an inconsistent view of the
> server configuration capabilities. It may be convenient to describe a
> "write-once at a very-specific time" attribute as RW, but this is
> fitting a round peg in a square hole (it may fit, but it rattles
> around a lot and could break as a result).
I think our current lifecycle based approach is quite workable as long
as you use it as described in my previous post.
As I understand it you are suggesting replacing the jboss lifecycle
idea with the following:
1. All attributes that currently require lifecycle state changes should
be made read only and set in the mbean constructor.
2. There should be some easy to use way to recreate an mbean with the
same object name, some unchanged attributes, but new constructor
arguments, at least as easy as the current "stop-change-start"
technique.
3. No lifecycle methods.
This might work, I haven't thought of any fatal problems with it.
+: Currently most of our mbeans are probably insufficiently
synchronized. By setting all arguments in the constructor, such
problems could perhaps be reduced.
-: This would require rewriting nearly every jboss mbean.
I'd like to see more advantages before undertaking such an enormous
project.
david jencks
>
> What you need is an Object-creation descriptor that says "pass these
> arguments to the constructor of object X". Then the value will be set
> *before* the object is loaded into the MBean server, and there is no
> need to name any attributes RW spuriously.
>
> I think that it is possible that the XMBean descriptor has something
> like this -- perhaps this is the best option.
>
> The take-home message here is that MBean Persistence is a
> cross-cutting concern. As such, I expect it to pull some skeletons
> out of the closet re: MBeans with inconsistent interfaces.
>
> - Matt
>
> -----Original Message-----
> From: [EMAIL PROTECTED] on behalf of
> Sacha Labourey
> Sent: Fri 1/24/2003 10:30 AM
> To: [EMAIL PROTECTED]
> Cc:
> Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> Configuration Service
>
>
> Not exatly.
>
> Take a look at the Naming Service MBean for example. It has a Port
> and IPAddress RW attribute for example because when the MBean is
> started the following occurs:
> - an instance of the Naming Service class is created (new blabla())
> - the attribute values found in jboss-service.xml for this mbean are
> assigned to the RW attributes of the Naming Service MBean
> - the service controller invokes create and then start on the MBean
> instance
> - inside the create/start methods, the Port/IPAddress attribute
> values are used to connect to the appropriate port
>
> Once this is done, changing the Port RW attribute will have *no*
> effect i.e. the naming service will not unbind/rebind with a new
> address/port. For this, you must stop the service, change the values
> and restart it. Do you follow me?
>
> Cheers,
>
>
> sacha
>
> -----Message d'origine-----
> De : Matt Munz
> [mailto:[EMAIL PROTECTED]]De la part de
> Matt Munz
> Envoyé : vendredi, 24 janvier 2003 15:59
> À : [EMAIL PROTECTED]
> Objet : RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> Configuration Service
>
>
> Sacha,
>
> I don't really understand. What good is a RW attribute if
> changing it has no effect? If this is really the case, then I think a
> lot of those RW attributes should be changed to RO. The whole idea of
> JMX is Management. The interface means something, right?
>
> - Matt
>
> -----Original Message-----
> From: [EMAIL PROTECTED] on behalf of
> Sacha Labourey
> Sent: Fri 1/24/2003 9:45 AM
> To: [EMAIL PROTECTED]
> Cc:
> Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> Configuration Service
>
>
> Oh, no, nothing wrong at all. It is just that while I can easily
> see an advantage to take a snapshot of a server config for future
> reference or analysis, re-loading a previous seems as hazardous to me
> because the configuration should really be applied when the mbeans are
> created, not afterwards because many settings would then have no
> effects at all (such as port numbers, etc.)
>
> Thank you. cheers,
>
>
> Sacha
>
> -----Message d'origine-----
> De : Matt Munz
> [mailto:[EMAIL PROTECTED]]De la part de
> Matt Munz
> Envoyé : vendredi, 24 janvier 2003 15:35
> À : [EMAIL PROTECTED]
> Objet : RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> Configuration Service
>
>
> Sacha,
>
> No. Nothing fancy going on here. Just a quick one-off
> proof-of-concept deal. What it does is make text-file-based mbean
> persistence available today, in a format perhaps more amenable to vi
> hackers.
>
> It's pretty simple to use -- why don't you just drop it in
> deploy and try it out...
>
> Basically, it takes and loads snapshots. Simple and useable. I
> suppose it could be modified to do other things...
>
> What is wrong with the jboss-service.xml files? I'm curious --
> What are you getting at?
>
> - Matt
>
> -----Original Message-----
> From: Sacha Labourey [mailto:[EMAIL PROTECTED]]
> Sent: Fri 1/24/2003 8:00 AM
> To: [EMAIL PROTECTED]
> Cc:
> Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> Configuration Service
>
>
>
> Can it be used at server startup instead of the
> jboss-service.xml, etc.
> files? i.e. can it create all Mbeans and apply all attributes
> value at
> runtime or can he "only" capture an instant snapshot of the
> current values?
>
> > -----Message d'origine-----
> > De : [EMAIL PROTECTED]
> > [mailto:[EMAIL PROTECTED]]De la
> part de Matt
> > Munz
> > Envoyé : mercredi, 22 janvier 2003 19:39
> > À : [EMAIL PROTECTED]
> > Objet : RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> > Configuration Service
> >
> >
> > BTW, I realize that the name "Master Configuration Service" may
> > be misleading. It only configures the JMX RW attributes, and
> > isn't really intended as a fundamental architectural component,
> > but rather as an optional tool and a POC for the flexibility of
> JMX.
> >
> > - Matt
> >
> > -----Original Message-----
> > From: Matt Munz
> > Sent: Wednesday, January 22, 2003 1:14 PM
> > To: [EMAIL PROTECTED]
> > Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> > Configuration Service
> >
> >
> > Bill,
> >
> > I read the forum, and I'm not sure how this relates to MBean
> > Persistence. Your examples seem to be AOP-specific. Could you
> > give an example of what the integration of this stuff with JMX
> > would be like (if that is what you intend)?
> >
> > - Matt
> >
> > -----Original Message-----
> > From: Bill Burke [mailto:[EMAIL PROTECTED]]
> > Sent: Wednesday, January 22, 2003 12:13 PM
> > To: [EMAIL PROTECTED]
> > Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> > Configuration Service
> >
> >
> > I am doing some things around MetaData and centralized
> configuration and
> > configuration chains in AOP that I'd like to merge with the
> rest of JBoss.
> > Please see the topic configuration and metadata in the AOP
> forum.
> >
> > Bill
> >
> > > -----Original Message-----
> > > From: [EMAIL PROTECTED]
> > > [mailto:[EMAIL PROTECTED]]On
> Behalf Of Matt
> > > Munz
> > > Sent: Wednesday, January 22, 2003 11:47 AM
> > > To: [EMAIL PROTECTED]
> > > Subject: RE: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> > > Configuration Service
> > >
> > >
> > > Dain,
> > >
> > > I put this together with your use cases in mind. If
> possible,
> > > check it out, and let me know what you think.
> > >
> > > - Matt
> > >
> > > -----Original Message-----
> > > From: SourceForge.net [mailto:[EMAIL PROTECTED]]
> > > Sent: Wednesday, January 22, 2003 11:29 AM
> > > To: [EMAIL PROTECTED]
> > > Subject: [JBoss-dev] [ jboss-Change Notes-672538 ] Master
> Configuration
> > > Service
> > >
> > >
> > > Change Notes item #672538, was opened at 2003-01-22 11:28
> > > You can respond by visiting:
> > >
> https://sourceforge.net/tracker/?func=detail&atid=381174&aid=67253
> > > 8&group_id=22866
> > >
> > > Category: None
> > > Group: None
> > > Status: Open
> > > Priority: 5
> > > Submitted By: Matthew Munz (mattmunz)
> > > Assigned to: Nobody/Anonymous (nobody)
> > > Summary: Master Configuration Service
> > >
> > > Initial Comment:
> > > A Service which writes and reads all of the JMX RW
> > > attributes to a single file in the Java Properties Format.
> > >
> > > I figured that this would be a good step on the road to an
> > > XML MBean Persistence engine. This service operates
> > > externally to the MBeans it persists. It is not really in
> > > line with the JMX spec, so it doesn't provide MBean
> > > Persistence in the way implied by the spec.
> > > Nonetheless, a "snapshot" of the server can be written
> > > and loaded quite easily.
> > >
> > > The details can be found in the documentation located
> > > under $jboss-head/varia/src/reources/master-
> > > config.sar/documentation .
> > >
> > > There are a few little details that should probably be
> > > ironed out, but for those that need MBean persistence
> > > today, this is a viable solution.
> > >
> > > The main audience for this tool is the system admin that
> > > does not use or prefer gui / html configuration tools. The
> > > use of the Properties file format is intentional, as it
> > > provides a more compact and readible interface when
> > > compared with the XML format.
> > >
> > > I'm not sure about the location of this code in the source
> > > tree, so I just put it in varia for now. I'd appreciate any
> > > ideas on a better place for it.
> > >
> > > - Matt Munz
> > >
> > >
> > >
> > >
> > >
> ----------------------------------------------------------------------
> > >
> > > You can respond by visiting:
> > >
> https://sourceforge.net/tracker/?func=detail&atid=381174&aid=67253
> > 8&group_id=22866
> >
> >
> > -------------------------------------------------------
> > This SF.net email is sponsored by: Scholarships for Techies!
> > Can't afford IT training? All 2003 ictp students receive
> scholarships.
> > Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and
> more.
> > www.ictp.com/training/sourceforge.asp
> > _______________________________________________
> > Jboss-development mailing list
> > [EMAIL PROTECTED]
> > https://lists.sourceforge.net/lists/listinfo/jboss-development
> >
> >
> > -------------------------------------------------------
> > This SF.net email is sponsored by: Scholarships for Techies!
> > Can't afford IT training? All 2003 ictp students receive
> scholarships.
> > Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and
> more.
> > www.ictp.com/training/sourceforge.asp
> > _______________________________________________
> > Jboss-development mailing list
> > [EMAIL PROTECTED]
> > https://lists.sourceforge.net/lists/listinfo/jboss-development
> >
> >
> >
> > -------------------------------------------------------
> > This SF.net email is sponsored by: Scholarships for Techies!
> > Can't afford IT training? All 2003 ictp students receive
> scholarships.
> > Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and
> more.
> > www.ictp.com/training/sourceforge.asp
> > _______________________________________________
> > Jboss-development mailing list
> > [EMAIL PROTECTED]
> > https://lists.sourceforge.net/lists/listinfo/jboss-development
> >
> >
> > -------------------------------------------------------
> > This SF.net email is sponsored by: Scholarships for Techies!
> > Can't afford IT training? All 2003 ictp students receive
> scholarships.
> > Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and
> more.
> > www.ictp.com/training/sourceforge.asp
> > _______________________________________________
> > Jboss-development mailing list
> > [EMAIL PROTECTED]
> > https://lists.sourceforge.net/lists/listinfo/jboss-development
> >
> >
> > -------------------------------------------------------
> > This SF.net email is sponsored by: Scholarships for Techies!
> > Can't afford IT training? All 2003 ictp students receive
> scholarships.
> > Get hands-on training in Microsoft, Cisco, Sun, Linux/UNIX, and
> more.
> > www.ictp.com/training/sourceforge.asp
> > _______________________________________________
> > Jboss-development mailing list
> > [EMAIL PROTECTED]
> > https://lists.sourceforge.net/lists/listinfo/jboss-development
> >
>
>
>
> -------------------------------------------------------
> This SF.NET email is sponsored by:
> SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2
> See!
> http://www.vasoftware.com
> _______________________________________________
> Jboss-development mailing list
> [EMAIL PROTECTED]
> https://lists.sourceforge.net/lists/listinfo/jboss-development
>
>
> <winmail.dat>
-------------------------------------------------------
This SF.NET email is sponsored by:
SourceForge Enterprise Edition + IBM + LinuxWorld =omething 2 See!
http://www.vasoftware.com
_______________________________________________
Jboss-development mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/jboss-development
-------------------------------------------------------
This SF.NET email is sponsored by:
SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See!
http://www.vasoftware.com
_______________________________________________
Jboss-development mailing list
[EMAIL PROTECTED]
https://lists.sourceforge.net/lists/listinfo/jboss-development
------------------------------------------------------- This SF.NET email is sponsored by: SourceForge Enterprise Edition + IBM + LinuxWorld = Something 2 See! http://www.vasoftware.com _______________________________________________ Jboss-development mailing list [EMAIL PROTECTED] https://lists.sourceforge.net/lists/listinfo/jboss-development
