Comments for All the small things http://osgi.mjahn.net that still do matter Thu, 06 Sep 2012 21:42:37 +0000 hourly 1 http://wordpress.org/?v=3.4.1 Comment on OSGi vs. Jigsaw – Why can’t we TALK? by shuron http://osgi.mjahn.net/2009/07/01/osgi-vs-jigsaw-why-cant-we-talk/#comment-701 shuron Thu, 06 Sep 2012 21:42:37 +0000 http://osgi.mjahn.net/?p=164#comment-701 Yout wrote this down july 2009. Today we have Septemeber 2012 and Jigsaw will not be delivered in Java 8 next year... :( Yout wrote this down july 2009. Today we have Septemeber 2012 and Jigsaw will not be delivered in Java 8 next year… :(

]]> Comment on The Quest for Software Reuse by shuron http://osgi.mjahn.net/2009/04/23/the-quest-for-software-reuse/#comment-700 shuron Thu, 06 Sep 2012 21:35:27 +0000 http://osgi.mjahn.net/?p=144#comment-700 And again I agree with the idea that a repository takes verification and control. And again I agree with the idea that a repository takes verification and control.

]]> Comment on The myth of software reuse by shuron http://osgi.mjahn.net/2009/04/02/the-myth-of-software-reuse/#comment-699 shuron Thu, 06 Sep 2012 20:16:53 +0000 http://osgi.mjahn.net/?p=117#comment-699 This article is not new but hasn't lost its relevance. I'm not new in OSGi, because of being ever on Eclipse IDE and sometimes doing Eclipse RCP development, but looking closer on OSGi in a last time. You describe here not only OSGi relevant topic. Versioning is big problem in a maven world. So my 5 cents are: The are two problems, first is to define what is the proper version strategy and who defines it and maintenance this rules. Second who and how controls the preservation of the rules. First is maybe simple. OSGi Alliance is encourage do define some kind of spec on this. But the control has to be done carefully. Thereby i think about a popular (has to be bright accepted ) OSGi Bundle repository (like maven has) which enables some contol function. Some simple control can be done e.g. during publishing and lead to refusing of deployment to Repo. Deeper and even semantic control could be done by human comunity. And there is a lot of opportunities how this could be relised, maybe it has to be not specified to detailed. What do you think? This article is not new but hasn’t lost its relevance. I’m not new in OSGi, because of being ever on Eclipse IDE and sometimes doing Eclipse RCP development, but looking closer on OSGi in a last time.

You describe here not only OSGi relevant topic. Versioning is big problem in a maven world. So my 5 cents are:
The are two problems, first is to define what is the proper version strategy and who defines it and maintenance this rules.
Second who and how controls the preservation of the rules.

First is maybe simple. OSGi Alliance is encourage do define some kind of spec on this. But the control has to be done carefully. Thereby i think about a popular (has to be bright accepted ) OSGi Bundle repository (like maven has) which enables some contol function.

Some simple control can be done e.g. during publishing and lead to refusing of deployment to Repo. Deeper and even semantic control could be done by human comunity. And there is a lot of opportunities how this could be relised, maybe it has to be not specified to detailed.
What do you think?

]]> Comment on Inspect your OSGi container by Martijn van Iersel http://osgi.mjahn.net/2008/04/02/inspect-your-osgi-container/#comment-8 Martijn van Iersel Fri, 02 Dec 2011 16:22:04 +0000 http://osgi.mjahn.net/2008/04/02/inspect-your-osgi-container/#comment-8 Thanks, that is very interesting. I do have a question: the documentation says to "register an instance of this object as a service with the Interface org.eclipse.osgi.framework.console.CommandProvider". How do I actually do that? Where in eclipse do I register services? Thanks, that is very interesting. I do have a question: the documentation says to “register an instance of this object as a service with the Interface org.eclipse.osgi.framework.console.CommandProvider”. How do I actually do that? Where in eclipse do I register services?

]]> Comment on Half bundle, half jar – the nature of a fragment, a blessing or a curse? by Vladislav Iliev http://osgi.mjahn.net/2008/03/13/half-bundle-half-jar-the-nature-of-fragment-a-blessing-or-a-curse/#comment-5 Vladislav Iliev Thu, 30 Dec 2010 08:45:36 +0000 http://osgi.mjahn.net/2008/03/13/half-bundle-half-jar-%e2%80%93-the-nature-of-fragment-a-blessing-or-a-curse/#comment-5 I've tried this example in Eclipse. When trying to start "BundleX" I'm getting a NoClassDefFound exception with the class in the package b: org.osgi.framework.BundleException: Exception in a.Activator.start() of bundle BundleX. at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:806) at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:755) at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:370) at org.eclipse.osgi.framework.internal.core.AbstractBundle.resume(AbstractBundle.java:374) at org.eclipse.osgi.framework.internal.core.Framework.resumeBundle(Framework.java:1067) at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:561) at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:546) at org.eclipse.osgi.framework.internal.core.StartLevelManager.incFWSL(StartLevelManager.java:459) at org.eclipse.osgi.framework.internal.core.StartLevelManager.doSetStartLevel(StartLevelManager.java:243) at org.eclipse.osgi.framework.internal.core.StartLevelManager.dispatchEvent(StartLevelManager.java:440) at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:227) at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:337) Caused by: java.lang.NoClassDefFoundError: b/BundleClassInPackageB at a.Activator.start(Activator.java:16) at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:783) at java.security.AccessController.doPrivileged(Native Method) at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:774) ... 11 more Caused by: java.lang.ClassNotFoundException: b.BundleClassInPackageB at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:460) at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:422) at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:410) at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107) at java.lang.ClassLoader.loadClass(Unknown Source) ... 15 more If I go in MANIFEST.MF for the fragment and remove the import of the b package (exported by Bundle Z), then everything goes well, the BundleX class in package b is loaded. So finally I think this issue is covered and no unexpected behavior (implementation) would be injected to the poor developer of Bundle X. I’ve tried this example in Eclipse.
When trying to start “BundleX” I’m getting a NoClassDefFound exception with the class in the package b:

org.osgi.framework.BundleException: Exception in a.Activator.start() of bundle BundleX.
at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:806)
at org.eclipse.osgi.framework.internal.core.BundleContextImpl.start(BundleContextImpl.java:755)
at org.eclipse.osgi.framework.internal.core.BundleHost.startWorker(BundleHost.java:370)
at org.eclipse.osgi.framework.internal.core.AbstractBundle.resume(AbstractBundle.java:374)
at org.eclipse.osgi.framework.internal.core.Framework.resumeBundle(Framework.java:1067)
at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:561)
at org.eclipse.osgi.framework.internal.core.StartLevelManager.resumeBundles(StartLevelManager.java:546)
at org.eclipse.osgi.framework.internal.core.StartLevelManager.incFWSL(StartLevelManager.java:459)
at org.eclipse.osgi.framework.internal.core.StartLevelManager.doSetStartLevel(StartLevelManager.java:243)
at org.eclipse.osgi.framework.internal.core.StartLevelManager.dispatchEvent(StartLevelManager.java:440)
at org.eclipse.osgi.framework.eventmgr.EventManager.dispatchEvent(EventManager.java:227)
at org.eclipse.osgi.framework.eventmgr.EventManager$EventThread.run(EventManager.java:337)
Caused by: java.lang.NoClassDefFoundError: b/BundleClassInPackageB
at a.Activator.start(Activator.java:16)
at org.eclipse.osgi.framework.internal.core.BundleContextImpl$1.run(BundleContextImpl.java:783)
at java.security.AccessController.doPrivileged(Native Method)
at org.eclipse.osgi.framework.internal.core.BundleContextImpl.startActivator(BundleContextImpl.java:774)
… 11 more
Caused by: java.lang.ClassNotFoundException: b.BundleClassInPackageB
at org.eclipse.osgi.internal.loader.BundleLoader.findClassInternal(BundleLoader.java:460)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:422)
at org.eclipse.osgi.internal.loader.BundleLoader.findClass(BundleLoader.java:410)
at org.eclipse.osgi.internal.baseadaptor.DefaultClassLoader.loadClass(DefaultClassLoader.java:107)
at java.lang.ClassLoader.loadClass(Unknown Source)
… 15 more

If I go in MANIFEST.MF for the fragment and remove the import of the b package (exported by Bundle Z), then everything goes well, the
BundleX class in package b is loaded.

So finally I think this issue is covered and no unexpected behavior (implementation) would be injected to the poor developer of Bundle X.

]]> Comment on Some thought on the OSGi R4.2 early draft by Martin Zdila http://osgi.mjahn.net/2008/08/28/some-thought-on-the-osgi-r42-early-draft/#comment-49 Martin Zdila Wed, 22 Sep 2010 07:53:38 +0000 http://osgi.mjahn.net/?p=40#comment-49 I don't agree that Spring-DM is way superiour to DS. They both use different approach. We switched our project from Spring-DM to DS. Problem with Spring-DM is that it relies on proxies and there was no tool to find out a missing dependency. We often had to wait until the dependency timeouts (default 5 minutes?). Now with DS it is very simple to find the dependency issue (scr info ). Also DS forces us do define one component.xml for one service. This is correct. DS is also more lightweight and low level (no proxies...) = better control and easier to debug. I don’t agree that Spring-DM is way superiour to DS. They both use different approach.

We switched our project from Spring-DM to DS. Problem with Spring-DM is that it relies on proxies and there was no tool to find out a missing dependency. We often had to wait until the dependency timeouts (default 5 minutes?). Now with DS it is very simple to find the dependency issue (scr info ). Also DS forces us do define one component.xml for one service. This is correct. DS is also more lightweight and low level (no proxies…) = better control and easier to debug.

]]> Comment on Making myself obsolete – well maybe. by Mirko Jahn http://osgi.mjahn.net/2010/03/03/making-myself-obsolete-well-maybe/#comment-78 Mirko Jahn Wed, 03 Mar 2010 12:14:33 +0000 http://osgi.mjahn.net/?p=212#comment-78 Thanks to Ina. She came up with the logo and I found it pretty cool, I have to admit! ;-) [WORDPRESS HASHCASH] The poster sent us '0 which is not a hashcash value. Thanks to Ina. She came up with the logo and I found it pretty cool, I have to admit! ;-)

[WORDPRESS HASHCASH] The poster sent us ’0 which is not a hashcash value.

]]> Comment on Making myself obsolete – well maybe. by Kaloyan http://osgi.mjahn.net/2010/03/03/making-myself-obsolete-well-maybe/#comment-77 Kaloyan Wed, 03 Mar 2010 08:06:13 +0000 http://osgi.mjahn.net/?p=212#comment-77 Awesome ! The inspector avatar is sooo looking like you :) Awesome ! The inspector avatar is sooo looking like you :)

]]> Comment on Is there a future for software versioning? by Eng http://osgi.mjahn.net/2009/12/15/is-there-a-future-for-software-versioning/#comment-76 Eng Mon, 01 Mar 2010 09:39:50 +0000 http://osgi.mjahn.net/?p=184#comment-76 In the field of software engineering any new updates in the technology is termed as version, advanced version, latest version etc. This is what the basic knowledge about "version" i had. Now came to know more. Thanks for the information In the field of software engineering any new updates in the technology is termed as version, advanced version, latest version etc. This is what the basic knowledge about “version” i had. Now came to know more. Thanks for the information

]]> Comment on The Quest for Software Reuse by Rui Curado http://osgi.mjahn.net/2009/04/23/the-quest-for-software-reuse/#comment-70 Rui Curado Thu, 25 Feb 2010 23:37:06 +0000 http://osgi.mjahn.net/?p=144#comment-70 You might want to have a look at ABSE (http://www.abse.info). ABSE is a Model-Driven Development approach with a strong focus on reuse. You might want to have a look at ABSE (http://www.abse.info). ABSE is a Model-Driven Development approach with a strong focus on reuse.

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