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From Peter Firmstone <j...@zeus.net.au>
Subject Re: River & OSGi
Date Thu, 19 Nov 2009 07:13:02 GMT
Mike you need to stop sounding like your looking down from the top of 
the podium and adopt a little humility in your comments.  Do try to be a 
little more agreeable.  Otherwise it rubs people the wrong way, which 
just isn't productive.  If your on the run all the time, perhaps you 
might want to get a netbook instead of the iPhone, then you can open an 
ide too.  Much better for participating.

I think that what comes across as an attitude of I know better and your 
wrong (whether intended or not) on the dev list is what puts people off 
participating.  Nobody wants to argue the details, we want to feel like 
we're contributing something.  We need to encourage people to try, 
perhaps we can set up an experimental area for would be committers, if 
need be, so they gain confidence to participate, more knowledgeable 
people can have a look and make suggestions and assist.  Once you start 
to get to know the codebase it isn't that hard to work with, I've been 
creating jUnit tests from the integration test code when I make changes 
to a class, it's pretty easy to do in your ide and the test results are 
instant.  Every now and then you can run the integration and jtreg tests.

I downloaded your code from svn on kharma, have had a brief look and 
plan to look into it further, while doing so I thought to myself, here 
is someone who can write code,  why are we having so much trouble 
communicating?

You know when I talk to the great coders, their attitude is never one of 
superiority, it's always one of generosity and assistance, they're just 
happy to help with whatever problem your experiencing.  I think that's 
what distinguishes the great programmers, communication, it is reflected 
in their code too, and I'm not talking about comments, I mean you read 
the code, the names of methods and classes, the intent is just obvious.  
But then look on find bugs, even the best are still human.

One word of advise about life, once you realise your own mortality and 
stare death in the face, before your time, especially when you have 
children, you wont worry so much about the technicalities, the little 
things just don't bother you anymore.  Make the most of life while it 
lasts, it really is fleeting.  It's not what you have that matters, its 
who.  Everything we argue over today will be forgotten tomorrow.

Best Regards,

Peter.



Mike McGrady wrote:
>
>
> Sent from my iPhone
>
> On Nov 18, 2009, at 8:59 PM, Sam Chance <sgchance@gmail.com> wrote:
>
>> Mike,
>>
>> The typos and comments in your "reply" suggest you may be tired or a
>> little under "some" influence.
>
> I am using an iPhone and haven't taken a single intoxicant for 
> millenia.  iPhones make up there own spelling at times.
>
>>
>> If your "SOA experience" is typical, I can almost guarantee that it
>> consists of proliferating (SOAP-based) web services...so what?
>> Wrapping an interface in XML simply perpetuates the same brittle -
>> point-to-point - architecture.
>
> This is not true for real systems.
>
>>
>> As for SLA, you *must* be joking! SLA are one of the *missing* aspects
>> of "mainstream" SOA. In fact, only recently has SLA been elevated in
>> the dialog. I'm quite confident the "weighty SOA mindset" you posit is
>> based on WS-*.
>
> You are clearly confident but mistaken.  Try to get SDN data for the 
> FAA SWIM program your way.  Knowing about the data has virtually 
> nothing to do with actually getting it.
>
>
>>
>> I find it almost humorous that you seem to refute Jini and OSGi as
>> instances of SOA constructs. You may want to circle back and change
>> all the literature about these two SOA frameworks to reflect your
>> view. Good luck with that.
>
> SOA is not a framework.  SOA is an architecture in which the atomic 
> elements are business level services.  This is standard talk.
>
>>
>> I live and work in the DC area. I sense you do as well; or at least
>> you work on DoD or Federal government systems. That would explain your
>> view about "SOA". But I could be wrong.
>
> I dont live in DC.  I live in the Seattle area.
>
>
>>
>> I'd welcome the chance to meet with you and hammer out these issues.
>> I'm sure I could learn a lot...and *maybe* teach you a thing or two.
>> :-)
>>
>
> I am sure I could learn a lot from you.
>
>> If you want to see SLA implemented by the runtime in a policy and
>> model-driven way, look at the Paremus Service Fabric. (Seems like
>> groundhog day...again).
>
> Service level agreements are not implemented in code.  This is WHY SOA 
> works.
>
>>
>> Sam
>>
>>
>> On 11/18/09, Mike McGrady <mmcgrady@topiatechnology.com> wrote:
>>> I have been involved with some fairly mature and well known SOA
>>> systems for years and I certainly would never consider either Jini or
>>> OSGi to be anything remotely like a SOA netwrk.  SOA services are
>>> explicitly SLA based and defined by business rules outside any IT
>>> strictures.  That is the key to there success.
>>>
>>> Only in a general and inconsequential sense can OSGi be considered to
>>> have a registry.  Keeping syst state is not a registry.
>>>
>>> I wish this conversation, since it diverges willy milky from
>>> established computer science terminology could stuck to the 
>>> particulars.
>>>
>>> Just my thing and I probably have nothing more to say.
>>>
>>>
>>>
>>> Sent from my iPhone
>>>
>>> On Nov 18, 2009, at 5:14 PM, Sam Chance <sgchance@gmail.com> wrote:
>>>
>>>> Peter,
>>>>
>>>> I agree with the notion that Jini and OSGi both implement the publish,
>>>> find and bind interaction model/pattern/paradigm / whatever additional
>>>> related words one prefers. I've always described this construct as the
>>>> "operational model" of SOA. It is exceedingly obvious to even the most
>>>> casual observer that Jini and OSGi adhere to this. The essential
>>>> difference is - in general terms - OSGi implements "publish-find-bind"
>>>> in a local memory space (I.e. a JVM) and Jini implements this across
>>>> multiple memory spaces (I.e. distributed). In my view, it is precisely
>>>> this difference that yields the complimentary nature of the two [SOA]
>>>> frameworks.
>>>>
>>>> Ironically, although contemporary mainstream SOA "deployments", which
>>>> are arguably Just a Bunch Of Web Services (JBOWS), prescribe 'publish,
>>>> find and bind', they rely little on a registry (e.g. UDDI) for the
>>>> 'find' function. Instead, they achieve the 'find' function via a
>>>> highly distributed and decentralized mechanism called "WoM" (Word of
>>>> Mouth). :-)
>>>>
>>>> Sam
>>>>
>>>>
>>>> On 11/18/09, Michael McGrady <mmcgrady@topiatechnology.com> wrote:
>>>>> Peter,
>>>>>
>>>>> Okay.  I see.  You are not using "pattern" in the sense of pattern
>>>>> brought
>>>>> into computer science by the Gang of Four.  You are using that term
>>>>> more in
>>>>> a plain English sense.  I think this is misleading in this venue
>>>>> and would
>>>>> suggest that you use another word to avoid the possible
>>>>> misunderstanding
>>>>> that you meant "design pattern" as it is used in computer science.
>>>>>
>>>>> On a more substantial note, I don't think the "pattern" you discuss
>>>>> is the
>>>>> same at all for Jini and OSGi.  The services for OSGi are not like
>>>>> the
>>>>> services for SOA.  SOA services may or may not be akin to the
>>>>> services for
>>>>> Jini.  I am very careful about abstracting or generalizing because,
>>>>> although
>>>>> my first and last love in computer science is architecture, the
>>>>> devil is in
>>>>> the detail.
>>>>>
>>>>> For my part, I think it would be worthwhile to determine the level of
>>>>> Ossification you want.  For example, there would be no harm at all
>>>>> in seeing
>>>>> whether you can modularize the jar files into bundles.  Once that
>>>>> is done,
>>>>> then you can begin seeing how the actual processes in OSGi match
>>>>> those in
>>>>> Jini.  As yet, you do not even know, as I understand it, what OSGi
>>>>> services
>>>>> you want.  That would need to be determined, since you will be
>>>>> customizing
>>>>> them.
>>>>>
>>>>> I hope this is helpful and thank you for stating what you were
>>>>> thinking.
>>>>>
>>>>> Mike
>>>>>
>>>>>
>>>>> On Nov 17, 2009, at 8:33 PM, Peter Firmstone wrote:
>>>>>
>>>>>> Mike McGrady wrote:
>>>>>>> I am presently the author of a framework called "Karma" (Kolona
>>>>>>> Automated
>>>>>>> Resource Management Architecture) that is open source with a
>>>>>>> management
>>>>>>> app under another open source framework AUM (Automated Universal
>>>>>>> Middleware).
>>>>>>>
>>>>>>> UM  (Universal Middleware) is a more current name for OSGi.
>>>>>>>
>>>>>>> We could have called it DUM (Distributed Universal Middleware)
>>>>>>> instead of
>>>>>>> AUM but thought better.
>>>>>>>
>>>>>>> Too bad we did not get on better when I asked you what you meant
by
>>>>>>> "Service Pattern".  (I still have no idea what you mean.)
>>>>>> Here's a Clarification of what I meant by "Service Pattern", from
>>>>>> Richards
>>>>>> Book, page 12, this should clear up any remaining confusion:
>>>>>>
>>>>>> "the service-oriented publish, find, and bind interaction pattern:
>>>>>> service
>>>>>> providers publish their services into a service registry, while
>>>>>> service
>>>>>> clients search the
>>>>>> registry to find available services to use (see Figure 1.3)."
>>>>>>
>>>>>> So there you go it's the "Publish, find and bind interaction
>>>>>> pattern"
>>>>>>
>>>>>> The point I was attempting to make in the beginning was that Jini,
>>>>>> OSGi,
>>>>>> ServiceLoader and Netbeans Modules all use the "Publish, find and
>>>>>> bind
>>>>>> interaction pattern" to solve different problems, I was trying to
>>>>>> lay out
>>>>>> the understanding to avoid an argument and promote a discussion
>>>>>> about how
>>>>>> to implement utilisation of OSGi within River and its applications.
>>>>>>
>>>>>> I still haven't managed to achieve this discussion, hopefully the
>>>>>> best way
>>>>>> forward will become more apparent during implementation.
>>>>>>
>>>>>> Cheers,
>>>>>>
>>>>>> Peter.
>>>>>>> Anyway, this does all you want to do and we have a plan to have
>>>>>>> it set as
>>>>>>> a standard with IEEE, where I am a member of the standards
>>>>>>> committee.  If
>>>>>>> you check there in a few months, you can see what I was hoping
to
>>>>>>> talk to
>>>>>>> you about before your ego got in the way.
>>>>>>>
>>>>>>> Good luck with your endeavors.
>>>>>>>
>>>>>>> Mike
>>>>>>>
>>>>>>> On Nov 8, 2009, at 5:06 PM, Peter Firmstone wrote:
>>>>>>>
>>>>>>>> Yes that's the beauty of Services, they provide opportunity
for
>>>>>>>> pluggable replacement implementations.  That's the "Service
>>>>>>>> Pattern"  As
>>>>>>>> we have seen it is possible to use the Service Pattern to
solve
>>>>>>>> a number
>>>>>>>> of different problems.  Eg Netbean Plugins, SPI, OSGi, Jini.
>>>>>>>>
>>>>>>>> I'm looking at OSGi to wire up services inside the JVM as
you
>>>>>>>> say.  When
>>>>>>>> I say package, I mean a java package residing in the local
JVM
>>>>>>>> it may or
>>>>>>>> may not be part of a Jini service, it may be a purely local
JVM
>>>>>>>> package,
>>>>>>>> eg a library dependency or local domain package.  For example,
I
>>>>>>>> have
>>>>>>>> package X, version 1 loaded in my local JVM, I need to have
>>>>>>>> package X
>>>>>>>> version 2 loaded as version 1 isn't compatible with the new
>>>>>>>> Objects
>>>>>>>> (domain data) I'm recieving in serialized form.  I need to
share
>>>>>>>> this
>>>>>>>> information locally with Package Y that currently has references
>>>>>>>> to
>>>>>>>> objects in Package X version 1.  The Objects in Package X
>>>>>>>> version 1 that
>>>>>>>> Package Y references need to have their class files upgraded.
>>>>>>>> Without
>>>>>>>> OSGi I can do this by persisting state, stopping the JVM,
>>>>>>>> restarting and
>>>>>>>> loading package X version 2.
>>>>>>>>
>>>>>>>> I'm not looking at distributed OSGi, but I can see a use
case for
>>>>>>>> utilising a Jini Service, when a local OSGi bundle that performs
>>>>>>>> some
>>>>>>>> task that could be done optimally if the processing can be
moved
>>>>>>>> to
>>>>>>>> where the data resides, this is just an example there are
>>>>>>>> probably 10
>>>>>>>> other ways of doing this:
>>>>>>>>
>>>>>>>> A local application bundle that provides an OSGi service
locally
>>>>>>>> queries
>>>>>>>> a remote database using JDBC and performs a considerable
amount of
>>>>>>>> manipulation to that data prior to returning a subset.  The
>>>>>>>> query and
>>>>>>>> its result are sent over the network using a database JDBC
>>>>>>>> connection.
>>>>>>>>
>>>>>>>> The processing for that data, if shifted to the machine that
has
>>>>>>>> the
>>>>>>>> database data, would consume significantly less network
>>>>>>>> resources.  EG
>>>>>>>> the data transferred over the network is reduced by a factor
of
>>>>>>>> 100 by
>>>>>>>> processing the data on the database machine after querying.
 A
>>>>>>>> bundle
>>>>>>>> that provides a "local JVM application" an "OSGi service"
could
>>>>>>>> utilise
>>>>>>>> a "Jini Service" to request the data be processed at the
Database
>>>>>>>> machine in a particular manner before receiving the result.
 This
>>>>>>>> function could be locally available as an OSGi service to
some
>>>>>>>> other
>>>>>>>> local application, that application doesn't need to know
about
>>>>>>>> Jini, it
>>>>>>>> is an implementation detail that is abstracted.
>>>>>>>>
>>>>>>>> My objectives are all based around codebase services (objects
>>>>>>>> aren't
>>>>>>>> locked to their http codebase origin), in combination with
OSGi or
>>>>>>>> something like it, to ensure compatible classes and packages
are
>>>>>>>> loaded
>>>>>>>> among separate JVM instances.  Yes Newton does something
similar,
>>>>>>>> however it is AGPLv3 licensed.
>>>>>>>>
>>>>>>>> I envision a distributed environment where nodes can have
the
>>>>>>>> majority
>>>>>>>> of their packages downloaded and upgraded via codebase servcies.
>>>>>>>> Providing an evolving cluster, that upgrades it's bundles
>>>>>>>> incrementally,
>>>>>>>> while maintaining the maximum level of class and package
>>>>>>>> compatibility.
>>>>>>>> Think Agile Cluster Running System component upgrades.
>>>>>>>>
>>>>>>>> People, who are jumping in now because I've mentioned OSGi,
are
>>>>>>>> making
>>>>>>>> assumptions and haven't been following the discussions I've
posted
>>>>>>>> previously about Versioned Classes, Classloader trees, Static
>>>>>>>> Analysis
>>>>>>>> and Codebase Services, this is frustrating as I was hoping
for
>>>>>>>> some
>>>>>>>> participation.  It seems I can only get attention when I
mention a
>>>>>>>> controversial subject.  What I want is attention to solving
the
>>>>>>>> problems
>>>>>>>> that will make River better.
>>>>>>>>
>>>>>>>> In my note below when I'm referring to the "Service Pattern",
I
>>>>>>>> mean the
>>>>>>>> service pattern that OSGi implements, enables bundles to
be
>>>>>>>> upgraded by
>>>>>>>> loading the replacement bundle in a new classloader,  The
>>>>>>>> service is a
>>>>>>>> common interface, the new upgraded service is discovered
after
>>>>>>>> it is
>>>>>>>> started.  The alternative is to use delegates to update references
>>>>>>>> between objects when the Classloader changes as per some
of the
>>>>>>>> other
>>>>>>>> patches I've uploaded.
>>>>>>>>
>>>>>>>> Jini also utilises a "Service Pattern", but to solve a different
>>>>>>>> problem.
>>>>>>>>
>>>>>>>> I knew this was going to be a difficult topic to present.
>>>>>>>>
>>>>>>>> What we need are separate lists, where people who want to
>>>>>>>> participate in
>>>>>>>> constructive development to solve problems can do so and
another
>>>>>>>> list
>>>>>>>> where people can pontificate about software ideals and have
>>>>>>>> disrespectful arguments with each other without holding up
>>>>>>>> development.
>>>>>>>> While we're developing we can keep an eye on the argument
list
>>>>>>>> without
>>>>>>>> getting embroiled.
>>>>>>>>
>>>>>>>> Anyway I've said enough, I'm going back to doing the things
I
>>>>>>>> need to
>>>>>>>> do, if someone who has been following my posts to date has
>>>>>>>> implementation ideas, but are afraid to mention it, please
feel
>>>>>>>> free to
>>>>>>>> contact me directly to discuss, I do need some input to gain
>>>>>>>> confidence
>>>>>>>> that I'm approaching these problems in the right manner.
>>>>>>>>
>>>>>>>> Peter.
>>>>>>>>
>>>>>>>> Dennis Reedy wrote:
>>>>>>>>>
>>>>>>>>> On Nov 8, 2009, at 1251AM, Peter Firmstone wrote:
>>>>>>>>>>
>>>>>>>>>> I had avoided OSGi purely due to the controversy
it generates
>>>>>>>>>> on this
>>>>>>>>>> list, however without the Service Pattern one cannot
upgrade a
>>>>>>>>>> package
>>>>>>>>>> without first persisting everything and shutting
down the
>>>>>>>>>> entire JVM,
>>>>>>>>>> then restarting.  At least OSGi allows you to stop
a bundle
>>>>>>>>>> and any
>>>>>>>>>> dependents, persist what you need to then start with
a later
>>>>>>>>>> bundle
>>>>>>>>>> version if desired, without having to persist or
shut down the
>>>>>>>>>> entire
>>>>>>>>>> JVM.
>>>>>>>>>
>>>>>>>>> If thats all you want you dont need OSGi. Service lifecycles
are
>>>>>>>>> supported with a variety of container approaches, from
JEE,
>>>>>>>>> Spring to
>>>>>>>>> Rio. You also do not need to shutdown the JVM to load
new service
>>>>>>>>> classes.
>>>>>>>>>
>>>>>>>>> Adopting OSGi as a micro-kernel architecture for wiring
up
>>>>>>>>> services
>>>>>>>>> inside the JVM is a different thing. Looking at distributed
>>>>>>>>> OSGi is a
>>>>>>>>> totally different thing on top of that. IMO, if you want
to
>>>>>>>>> consider
>>>>>>>>> OSGi for River, you focus on the former, not the latter.
>>>>>>>>>
>>>>>>>>>
>>>>>>>>>
>>>>>>>>
>>>>>>>
>>>>>>> Mike McGrady
>>>>>>> Principal Investigator AF081-028 AFRL SBIR
>>>>>>> Senior Engineer
>>>>>>> Topia Technology, Inc.
>>>>>>> 1.253.720.3365
>>>>>>> mmcgrady@topiatechnology.com
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>>
>>>>>>
>>>>>
>>>>>
>>>>
>>>> -- 
>>>> Sent from my mobile device
>>>>
>>>> Sam Chance
>>>> 443-694-5293 (m)
>>>> 410-694-0240 x108 (o)
>>>
>>
>> -- 
>> Sent from my mobile device
>>
>> Sam Chance
>> 443-694-5293 (m)
>> 410-694-0240 x108 (o)
>


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