Re: Osgifing Tomcat

2008-05-01 Thread Costin Manolache
Long thread, my summary: 1. Adding OSGI manifests to tomcat jars: there is interest, it will provide benefits for people using tomcat in an OSGI environment. I don't think there is any major controversy - it'll not affect any existing functionality. If Henri or someone familiar with OSGi and inter

Re: Osgifing Tomcat

2008-05-01 Thread Jim Manico
> I just don't have the time. If you keep your responses to a few short paragraphs, you might get more input Filip, hey. May I ask when you think the HttpOnly patch will go live? And Mark, I've spammed you about this as well - I'm running my own custom branch eager to back back inline with the

Re: Osgifing Tomcat

2008-05-01 Thread Filip Hanik - Dev Lists
Peter Kriens wrote: I must admit I feel I am walking on eggs ... and I am a bit surprised how few others tune in. there is a reason few others turn in, at this point, you have written, and very well so, about 30 pages of responses. It's just to hard keep up with long essays like that, not t

Re: Osgifing Tomcat

2008-05-01 Thread Peter Kriens
Regarding 'dynamic register/unregister' - the servlet API defines one way to do this, i.e. war and the deployment. There is no standard API to install/uninstall/start/stop a .war - but HttpService is not that either. Runtime config changes ( adding/removing servlets without web.xml changes an

Re: Osgifing Tomcat

2008-04-30 Thread David Jencks
On Apr 30, 2008, at 10:28 AM, Costin Manolache wrote: On Wed, Apr 30, 2008 at 1:00 AM, Peter Kriens <[EMAIL PROTECTED]> wrote: Regarding HttpService - I don't think it's a good idea for tomcat. One of the major problems with OSGI ( and we need to make sure we don't fall in this trap ) is t

Re: Osgifing Tomcat

2008-04-30 Thread Costin Manolache
On Wed, Apr 30, 2008 at 1:00 AM, Peter Kriens <[EMAIL PROTECTED]> wrote: > Regarding HttpService - I don't think it's a good idea for tomcat. > > One of the major problems with OSGI ( and we need to make sure we don't > > fall > > in this trap ) is the re-invention of common APIs - logging, servle

Re: Osgifing Tomcat

2008-04-30 Thread Niall Pemberton
On Tue, Apr 22, 2008 at 11:45 AM, Henri Gomez <[EMAIL PROTECTED]> wrote: > Hi to all, > > Did there is plans, ideas or interest around about OSGI-fing Tomcat ? Quotes from http://www.infoq.com/news/2008/04/springsource-app-platform "...the SpringSource Application Platform, an application server

Re: Osgifing Tomcat

2008-04-30 Thread Peter Kriens
Regarding HttpService - I don't think it's a good idea for tomcat. One of the major problems with OSGI ( and we need to make sure we don't fall in this trap ) is the re-invention of common APIs - logging, servlet interfaces, etc. As a bit of background. The logging and Http Service API are fro

Re: Osgifing Tomcat

2008-04-29 Thread Costin Manolache
Well, IMHO the servlet spec is going from bad to worse in terms of complexity and feature bloat, so careful what you wish :-) My point was mostly that we don't have to implement OSGI HttpService, it may be ok to use them for modularization but for servlet-specific APIs we should stick with the JSR

Re: Osgifing Tomcat

2008-04-29 Thread Henri Gomez
> You should try to read the article I think :) This is about a specific > issue, where there's no actual disagreement (basically it is a publicity > stunt). I read it carefully Remy, don't worry. There is open discussion on Servlet 3.0 and may be the opportunity to discuss more than just disc

Re: Osgifing Tomcat

2008-04-29 Thread Remy Maucherat
On Tue, 2008-04-29 at 22:12 +0200, Henri Gomez wrote: > Read on serverside that JSR-315 needs ideas for servlet 3.0 specs. You should try to read the article I think :) This is about a specific issue, where there's no actual disagreement (basically it is a publicity stunt). Rémy --

Re: Osgifing Tomcat

2008-04-29 Thread Henri Gomez
Read on serverside that JSR-315 needs ideas for servlet 3.0 specs. http://www.theserverside.com/news/thread.tss?thread_id=49212 May be a good opportunity to send various requests about dynamic reload purposes (with or without OSGI) to the JCR. Regards --

Re: Osgifing Tomcat

2008-04-29 Thread Costin Manolache
On Mon, Apr 28, 2008 at 11:25 PM, Peter Kriens <[EMAIL PROTECTED]> wrote: > Tomcat to really make a lot of sense. Providing OSGi headers seems to > fulfill > the immediate need of several groups. However, it would be really nice if > you > could provide a service interface like an Http Service (

Re: Osgifing Tomcat

2008-04-28 Thread Peter Kriens
Please, I think the audience is pretty much "mature" developpers here :-) I know, that is why it is scary and sounds complex because experienced developers know much better what can go wrong. Novices have much fewer qualms. :-) Anyway, the dynamism is not Eclipse's strongest feature, but the

Re: Osgifing Tomcat

2008-04-28 Thread Damien B
On Mon, Apr 28, 2008 at 12:52 PM, pkriens wrote: > > To me, a webapp adds "entries" (aka Servlet) to menus (aka url patterns) > > from a static file inside the war (web.xml). If it was not possible in 4 > > years to solve this problem in Eclipse, how will it be possible for > > Tomcat? > More and m

Re: Osgifing Tomcat

2008-04-28 Thread pkriens
> To me, a webapp adds "entries" (aka Servlet) to menus (aka url patterns) > from a static file inside the war (web.xml). If it was not possible in 4 > years to solve this problem in Eclipse, how will it be possible for > Tomcat? More and more code is supporting the dynamic life cycle model beca

Re: Osgifing Tomcat

2008-04-28 Thread Damien B
pkriens wrote: Just my 2c: Eclipse, OSGified since 3.2, still doesn't fully support updates without a JVM restart; and they have full control about the whole aspects. Unfortunately there are tens of thousands of plugin writers out there that are not aware of the dynamics. Eclipse migrated to OS

Re: Osgifing Tomcat

2008-04-28 Thread pkriens
> Someone recently pointed out to me that the Bnd tool comes with ant > tasks. I haven't tried that (we've used maven in commons) and I > suspect that there isn't the option to just produce the manifest > (rather than jar and manifest) as there is in the maven plugin. If > that was required then i

Re: Osgifing Tomcat

2008-04-28 Thread pkriens
> my feeling is though, is that you are going for the "mavenization" just > to run the BND or BNE or whatever the plugin is called, that generates > the OSGi manifests. The project is called bnd (pronounce b and d). The jar can be used as an ant task, command utility, eclipse plugin, and library

Re: Osgifing Tomcat

2008-04-27 Thread pkriens
> I think the first main problem with these frameworks is how intrusive > they are, esp compared with whet they provide :( I suppose there's no > problem with doing a tomcat-osgi in the sandbox if people want to. As I > said I really don't care. We tried awfully hard to be not intrusive :-( Actua

Re: Osgifing Tomcat

2008-04-27 Thread pkriens
> Just my 2c: Eclipse, OSGified since 3.2, still doesn't fully support > updates without a JVM restart; and they have full control about the > whole aspects. Unfortunately there are tens of thousands of plugin writers out there that are not aware of the dynamics. Eclipse migrated to OSGi 4 years

Re: Osgifing Tomcat

2008-04-27 Thread pkriens
The way the dynamics work in OSGi is only partly classloading. In the HTTP examples, we have defined an HttpService where you register a servlet. When a bundle (OSGi JAR) is started, it registers a servlet with the http service. When it is stopped, the Http Service detects this and removes the map

Re: Osgifing Tomcat

2008-04-27 Thread pkriens
> I've heard various claims of this nature from osgi zealots, but when > talking to apparent experts the only things resembling this they > seemed to know about were grad student experiments that did not have > production use as even a far-in-the-future goal. Do you know of any > actual e

Re: Osgifing Tomcat

2008-04-25 Thread Henri Gomez
> But I think the main question is if it's worth it - there is a lot of > complexity and many things that can go wrong. Very few advanced users > will be able to use this - in particular if they have production > environments and some release testing is required ( i.e. it would be > quite hard

Re: Osgifing Tomcat

2008-04-25 Thread Costin Manolache
On Fri, Apr 25, 2008 at 12:49 AM, David Jencks <[EMAIL PROTECTED]> wrote: > > On Apr 24, 2008, at 11:11 PM, Henri Gomez wrote: > > > > > > > I've heard various claims of this nature from osgi zealots, but when > > > talking to apparent experts the only things resembling this they seemed > to > > >

Re: Osgifing Tomcat

2008-04-25 Thread Damien B
David Jencks wrote: > On Apr 24, 2008, at 11:11 PM, Henri Gomez wrote: > > We'll see how OSGI works underload with Glassfish v3. Are they planning to support "gapless" redeployment of web apps using only osgi features, with no other servlet container support? If so is can you point to an explan

Re: Osgifing Tomcat

2008-04-25 Thread Henri Gomez
> Since this requires state mutation (see the hooks that an Erlang OTP > application will supply for state upgrade, for instance) there won't be > a "no other hooks" version, I think :-) > > This is doable (I've done it, but only as a proof of concept - as > pointed out, this is a long way awa

Re: Osgifing Tomcat

2008-04-25 Thread Jan Grant
On Fri, 25 Apr 2008, David Jencks wrote: > Are they planning to support "gapless" redeployment of web apps using only > osgi features, with no other servlet container support? If so is can you > point to an explanation of how they plan to do this? Since this requires state mutation (see the hook

Re: Osgifing Tomcat

2008-04-25 Thread David Jencks
On Apr 24, 2008, at 11:11 PM, Henri Gomez wrote: I've heard various claims of this nature from osgi zealots, but when talking to apparent experts the only things resembling this they seemed to know about were grad student experiments that did not have production use as even a far-in-the-fut

Re: Osgifing Tomcat

2008-04-24 Thread Henri Gomez
> I've heard various claims of this nature from osgi zealots, but when > talking to apparent experts the only things resembling this they seemed to > know about were grad student experiments that did not have production use as > even a far-in-the-future goal. Do you know of any actual examples of

Re: Osgifing Tomcat

2008-04-24 Thread Henri Gomez
> OSGI is good of having 2 versions of a bundle running at the same time > - but it won't help you much, the servlet > engine needs to know where to send the requests, it has no clue a > request should go to the old version or the new. May be additions to servlet specs should be planned, ie, b

Re: Osgifing Tomcat

2008-04-24 Thread Costin Manolache
I'm not an expert, but I think I can tell you that yes, "hello world" applications can be upgraded without stopping, real applications can't. As long as you use sessions or statics or you make config changes - you have to restart the webapp. OSGI is good of having 2 versions of a bundle running at

Re: Osgifing Tomcat

2008-04-24 Thread David Jencks
On Apr 22, 2008, at 6:25 PM, Paul Benedict wrote: Is that enough so that web applications, either as a whole or in partial, can be upgraded without stopping them? It's my understanding that if web applications are loaded in an OSGi classloader, these kind of things are possible. I've hea

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> That's maven's problem - I don't think there is any value in > continuing this discussion, > again - if you can support maven by adding a build/maven directory and > whatever files > inside - you have my +1, I'm all for making it easy to build - as long > as the tools are not > intrusive a

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
On Wed, Apr 23, 2008 at 1:38 PM, Henri Gomez <[EMAIL PROTECTED]> wrote: > > And that would be the reason for -1. > > If a build system requires intrusive changes and forces a particular code > > organization - it shouldn't be used. > > that's maven phylosophy, not so bad. The layout may be

Re: Osgifing Tomcat

2008-04-23 Thread Filip Hanik - Dev Lists
Niall Pemberton wrote: On Wed, Apr 23, 2008 at 6:56 PM, Filip Hanik - Dev Lists <[EMAIL PROTECTED]> wrote: Henri Gomez wrote: I'm not sure it's the best idea, my goal is to move it out of sandbox, it already has enough experiments that need completion. and the main goal is to be 'li

Re: Osgifing Tomcat

2008-04-23 Thread Niall Pemberton
On Wed, Apr 23, 2008 at 6:56 PM, Filip Hanik - Dev Lists <[EMAIL PROTECTED]> wrote: > > Henri Gomez wrote: > > > > > > I'm not sure it's the best idea, my goal is to move it out of sandbox, > > > it already has enough experiments > > > that need completion. and the main goal is to be 'lite' :-).

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
I grab jackrabbit and apacheds right now from eclipse : - added their repositories to eclipse - checkout maven project from SVN - got the main project and modules in the eclipse workspace - mvn package and voila it works ! Hard to be simpler :) Just a note, I'm not a maven evangelist :)

Re: Osgifing Tomcat

2008-04-23 Thread Filip Hanik - Dev Lists
Henri Gomez wrote: First define 'mavenizing' please :-) Yes If you mean exporting tomcat components in maven repository - fine with me. It's allready done (by hand) ? If you mean building tomcat with maven instead of ant - the opposite, absolutely not fine. it wa

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> > it was the idea. > > Sorry, -1 from me ( again ). Sic... > And that would be the reason for -1. > If a build system requires intrusive changes and forces a particular code > organization - it shouldn't be used. that's maven phylosophy, not so bad. > It is a choice each project can ma

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
On Wed, Apr 23, 2008 at 1:17 PM, Henri Gomez <[EMAIL PROTECTED]> wrote: > > First define 'mavenizing' please :-) > > Yes > > > > If you mean exporting tomcat components in maven repository - fine with > me. > > It's allready done (by hand) ? > > > > If you mean building tomcat with maven ins

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> First define 'mavenizing' please :-) Yes > If you mean exporting tomcat components in maven repository - fine with me. It's allready done (by hand) ? > If you mean building tomcat with maven instead of ant - the opposite, > absolutely not fine. it was the idea. > Maintaining a separate

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
First define 'mavenizing' please :-) If you mean exporting tomcat components in maven repository - fine with me. If you mean building tomcat with maven instead of ant - the opposite, absolutely not fine. Maintaining a separate maven build file - unofficial, i.e. the default build instructions sti

Re: Osgifing Tomcat

2008-04-23 Thread Filip Hanik - Dev Lists
hi Henri, Henri Gomez wrote: So nobody object for some experimentation around mavenizing Tomcat 6 ? no one can object what you do on your own time. It's your given right. However, if you look at the previous discussions around the Maven topic, you will see it is highly unlikely that the Tom

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
So nobody object for some experimentation around mavenizing Tomcat 6 ? Of course no commit just testing on my own eclipse/m2 workspace. >2008/4/23 Filip Hanik - Dev Lists <[EMAIL PROTECTED]>: > > Henri Gomez wrote: > > > > > > I'm not sure it's the best idea, my goal is to move it out of sandbox

Re: Osgifing Tomcat

2008-04-23 Thread Filip Hanik - Dev Lists
Henri Gomez wrote: I'm not sure it's the best idea, my goal is to move it out of sandbox, it already has enough experiments that need completion. and the main goal is to be 'lite' :-). It has a simple Addon mechanism, and I don't mind having an optional addon manager impl using OSGI - but I

Re: Osgifing Tomcat

2008-04-23 Thread Johnny Kewl
- Original Message - From: "Henri Gomez" <[EMAIL PROTECTED]> To: "Tomcat Developers List" Sent: Wednesday, April 23, 2008 2:24 PM Subject: Re: Osgifing Tomcat Yes, the modular aspect is for sure a better choice. So we can have a smaller Tomcat (by

Re: Osgifing Tomcat

2008-04-23 Thread Florent.BENOIT
Henri Gomez wrote: Indeed I'll try to spend some time on mavenize tomcatlight first and how it could be done then for tomcat trunk. Next how to OSGIfy the mavenized tomcats, experiences and advices welcomed here Once Tomcat has been mavenized, with maven-bundle-plugin you can produce bundl

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> I'm not sure it's the best idea, my goal is to move it out of sandbox, > it already has enough experiments > that need completion. and the main goal is to be 'lite' :-). It has a > simple Addon mechanism, and I don't mind > having an optional addon manager impl using OSGI - but I don't want

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
On Wed, Apr 23, 2008 at 8:36 AM, Henri Gomez <[EMAIL PROTECTED]> wrote: > > Silly question, but did experiments with OSGI could be done, first, in > tomcatlight ? > I'm not sure it's the best idea, my goal is to move it out of sandbox, it already has enough experiments that need completion. and

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> Well, adding OSGI-compatible manifests to the existing jars is not > that intrusive, > and could be easily done in the trunk. AFAIK an Activator is not required - > i.e. > if you don't need the BundleContext or to add services, you can have a bundle > that just imports/exports packages. > >

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
Well, adding OSGI-compatible manifests to the existing jars is not that intrusive, and could be easily done in the trunk. AFAIK an Activator is not required - i.e. if you don't need the BundleContext or to add services, you can have a bundle that just imports/exports packages. I agree with Remy th

Re: Osgifing Tomcat

2008-04-23 Thread Remy Maucherat
On Wed, 2008-04-23 at 16:00 +0200, Florent.BENOIT wrote: > Also, for OSGi, as all is done by package (import/export) the first step > is to be sure that API and Implementation are never in the same package > name. So we can export APIs and keep private the implementation. I think the first main

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> I'm actually working in sandbox, and I plan to propose stuff for the > trunk - and thus become active ( I'm very slow those days - I don't have a > lot of free time ). Ditto. I don't have a lot of free time, but I willing to take on my spare time for OSGIfying Tomcat. More all contributio

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> I share your concern about OSGI and hype :-) As a regular Eclipse user, I like OSGI, but from the plugin altitude. > I spent few years working on a project using OSGI heavily, with people > buying the hype. It was a big disaster, most time was spent > reinventing the wheels and turning perf

RE: Osgifing Tomcat

2008-04-23 Thread Jim Manico
Remy - please consider the Apache guidelines about being respectful on the public lists. Key word: please. - Jim -Original Message- From: Remy Maucherat <[EMAIL PROTECTED]> Sent: Wednesday, April 23, 2008 7:35 AM To: Tomcat Developers List Subject: Re: Osgifing Tomcat On Tue, 2

Re: Osgifing Tomcat

2008-04-23 Thread Florent.BENOIT
Yes, that looks great. Also, for OSGi, as all is done by package (import/export) the first step is to be sure that API and Implementation are never in the same package name. So we can export APIs and keep private the implementation. Florent Henri Gomez wrote: Yes, the modular aspect

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
> I don't know if you noticed, but I have not really been participating in > Tomcat's trunk development for months, and am only dealing with Tomcat > 6.0. In trunk or any other future developments, at the moment my plan is > only to comment (pretty much like Costin does). I'm actually working

Re: Osgifing Tomcat

2008-04-23 Thread Costin Manolache
On Wed, Apr 23, 2008 at 4:35 AM, Remy Maucherat <[EMAIL PROTECTED]> wrote: > On Tue, 2008-04-22 at 12:45 +0200, Henri Gomez wrote: > > Hi to all, > > > > Did there is plans, ideas or interest around about OSGI-fing Tomcat ? > > The only thing which ever attracts you is pointless hype, it's quit

Re: Osgifing Tomcat

2008-04-23 Thread Remy Maucherat
On Wed, 2008-04-23 at 14:23 +0200, Henri Gomez wrote: > > The only thing which ever attracts you is pointless hype, it's quite > > funny ;) > > Remy, I, and many others, will be happy, at least one time, see you > discuss technicals and usage aspects of a Tomcat evolution. > > * What's the pros

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
>Yes, the modular aspect is for sure a better choice. So we can have a > smaller Tomcat (by only using few bundles) or bundles loaded on demand. +1 And select which part of the engine to be used. What make HTTPD server so successfull was its modular approach and openess. ---

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> The only thing which ever attracts you is pointless hype, it's quite > funny ;) Remy, I, and many others, will be happy, at least one time, see you discuss technicals and usage aspects of a Tomcat evolution. * What's the pros and cons ? * Interest, usage, openess OSGI is not buzz, it's rea

Re: Osgifing Tomcat

2008-04-23 Thread Remy Maucherat
On Tue, 2008-04-22 at 12:45 +0200, Henri Gomez wrote: > Hi to all, > > Did there is plans, ideas or interest around about OSGI-fing Tomcat ? The only thing which ever attracts you is pointless hype, it's quite funny ;) Rémy -

Re: Osgifing Tomcat

2008-04-23 Thread Florent.BENOIT
Yes, the modular aspect is for sure a better choice. So we can have a smaller Tomcat (by only using few bundles) or bundles loaded on demand. Regards, Florent Filip Hanik - Dev Lists wrote: Henri Gomez wrote: 2008/4/23 Florent.BENOIT <[EMAIL PROTECTED]>: Hello, As part of OW2 JOn

Re: Osgifing Tomcat

2008-04-23 Thread Filip Hanik - Dev Lists
Henri Gomez wrote: 2008/4/23 Florent.BENOIT <[EMAIL PROTECTED]>: Hello, As part of OW2 JOnAS 5.0 OSGi based application server we're interested to have Tomcat packaged as an OSGi bundle. All our modules are bundles and if tomcat is already a bundle we won't have to wrap it into a bundle

Re: Osgifing Tomcat

2008-04-23 Thread Florent.BENOIT
Our bundle of Tomcat is exposing JOnAS service API. I think that from a tomcat bundle view it should expose its own interface like API for registering/deploying a war component, etc. If you want to see some source code, it's in the SVN. http://svn.forge.objectweb.org/cgi-bin/viewcvs.cgi/jonas

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
2008/4/23 Florent.BENOIT <[EMAIL PROTECTED]>: >Hello, > > As part of OW2 JOnAS 5.0 OSGi based application server we're interested to > have Tomcat packaged as an OSGi bundle. > All our modules are bundles and if tomcat is already a bundle we won't have > to wrap it into a bundle on our side.

Re: Osgifing Tomcat

2008-04-23 Thread Henri Gomez
> I've put a note about this a while ago in tomcat/trunk/PROPOSALS.txt > my original plan was just to make sure all the MANIFEST.MF for each file > would have enough in it so that each JAR can be a OSGi bundle. Well it shouldn't hurt updating MANIFEST.MF. Could you update some so we could take a

Re: Osgifing Tomcat

2008-04-23 Thread Florent.BENOIT
Hello, As part of OW2 JOnAS 5.0 OSGi based application server we're interested to have Tomcat packaged as an OSGi bundle. All our modules are bundles and if tomcat is already a bundle we won't have to wrap it into a bundle on our side. Regards, Florent Henri Gomez wrote: Hi to all, Did

Re: Osgifing Tomcat

2008-04-22 Thread Paul Benedict
Is that enough so that web applications, either as a whole or in partial, can be upgraded without stopping them? It's my understanding that if web applications are loaded in an OSGi classloader, these kind of things are possible. Paul On Tue, Apr 22, 2008 at 7:24 PM, Filip Hanik - Dev Lists <[EMA

Re: Osgifing Tomcat

2008-04-22 Thread Filip Hanik - Dev Lists
Henri Gomez wrote: Hi to all, Did there is plans, ideas or interest around about OSGI-fing Tomcat ? I've put a note about this a while ago in tomcat/trunk/PROPOSALS.txt my original plan was just to make sure all the MANIFEST.MF for each file would have enough in it so that each JAR can be a

Re: Osgifing Tomcat

2008-04-22 Thread Henri Gomez
2008/4/22, Costin Manolache <[EMAIL PROTECTED]>: > I think OSGI has some good ideas - it is pretty good at handling class > loaders and loading/unloading modules. On the other side, they are > very 'framework' - and like all other frameworks you have to do all > things their way and they re-inv

Re: Osgifing Tomcat

2008-04-22 Thread Costin Manolache
I think OSGI has some good ideas - it is pretty good at handling class loaders and loading/unloading modules. On the other side, they are very 'framework' - and like all other frameworks you have to do all things their way and they re-invent a lot of wheels ( from logging APIs to almost everything