# Jruby and ubuntu and libgcj **URL:** \ **Category:** Ruby\ **Created:** [August 11, 2008, 2:39pm UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553 "2008-08-11T14:39:59Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 11, 2008, 2:39pm UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/1 "2008-08-11T14:39:59Z")
Dear all, I have problems using jruby (1.1.3) on ubuntu 8.04, libgcj 4.2.3: axel@alecrim:~$ jruby -v Exception in thread “main” java.lang.NoClassDefFoundError: org.jruby.Main at gnu.java.lang.MainThread.run(libgcj.so.81) Caused by: java.lang.ClassNotFoundException: org.jruby.Main not found in gnu.gcj.runtime.SystemClassLoader{urls=[file:/usr/local/jruby-1.1.3/lib/bsf.jar,file:/usr/local/jruby-1.1.3/lib/profile.jar,file:./], parent=gnu.gcj.runtime.ExtensionClassLoader{urls=[], parent=null}} at java.net.URLClassLoader.findClass(libgcj.so.81) at gnu.gcj.runtime.SystemClassLoader.findClass(libgcj.so.81) at java.lang.ClassLoader.loadClass(libgcj.so.81) at java.lang.ClassLoader.loadClass(libgcj.so.81) at gnu.java.lang.MainThread.run(libgcj.so.81) > gij --version > java version “1.5.0” > gij (GNU libgcj) version 4.2.3 (Ubuntu 4.2.3-2ubuntu6) I found a similar bug report about earlier versions of jruby/ubuntu/gij versions here, where it is filed as a resolved bug … however, I can’t resolve it on my system: [http://jira.codehaus.org/browse/JRUBY-2254](http://jira.codehaus.org/browse/JRUBY-2254) Thank you for your help. Best regards, Axel ---
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 11, 2008, 6:32pm UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/2 "2008-08-11T18:32:19Z")
Axel E. wrote: > at java.lang.ClassLoader.loadClass(libgcj.so.81) > at java.lang.ClassLoader.loadClass(libgcj.so.81) > at gnu.java.lang.MainThread.run(libgcj.so.81) As far as I know, JRuby 1.1.3 neither compiles nor runs on GCJ, mostly because it’s missing several tools and libraries we need. We’re certainly open to someone getting it running, but with all the Linux distros now providing installable OpenJDK-based JVMs, there’s hasn’t been much interest in getting GCJ to work. - Charlie ---
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 11, 2008, 7:43pm UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/3 "2008-08-11T19:43:14Z")
-------- Original-Nachricht -------- > Datum: Tue, 12 Aug 2008 01:26:44 +0900 > Von: Charles Oliver N. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) > An: removed\_email\_address@domain.invalid > Betreff: Re: jruby and ubuntu and libgcj > gnu.gcj.runtime.SystemClassLoader{urls=[file:/usr/local/jruby-1.1.3/lib/bsf.jar,file:/usr/local/jruby-1.1.3/lib/profile.jar,file:./], > distros now providing installable OpenJDK-based JVMs, there’s hasn’t > been much interest in getting GCJ to work. > > - Charlie Dear Charles, thank you for responding. Could you advise which java virtual machine should be used for stress-free Jruby usage 🙂 ? Thank you, Best regards, Axel ---
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 11, 2008, 9:20pm UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/4 "2008-08-11T21:20:37Z")
On Mon, Aug 11, 2008 at 1:39 PM, Axel E. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid) wrote: > thank you for responding. Could you advise which java virtual machine should > be used for stress-free Jruby usage 🙂 ? (On Linux) I have either used Sun’s Java 6 JDK or (more recently moving toward) OpenJDK. I think on my Ubuntu box at home, I still have Sun’s release installed; but, Ubuntu 8.10 should have OpenJDK baked in: [https://lists.ubuntu.com/archives/ubuntu-devel-announce/2008-July/000460.html](https://lists.ubuntu.com/archives/ubuntu-devel-announce/2008-July/000460.html) ---
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 11, 2008, 11:00pm UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/5 "2008-08-11T23:00:51Z")
-------- Original-Nachricht -------- > Datum: Tue, 12 Aug 2008 04:16:58 +0900 > Von: removed\_email\_address@domain.invalid > An: removed\_email\_address@domain.invalid > Betreff: Re: jruby and ubuntu and libgcj > > thank you for responding. Could you advise which java virtual machine > > should > > be used for stress-free Jruby usage 🙂 ? > > (On Linux) I have either used Sun’s Java 6 JDK or (more recently > moving toward) OpenJDK. I think on my Ubuntu box at home, I still > have Sun’s release installed; but, Ubuntu 8.10 should have OpenJDK > baked in: > > [Java related changes in intrepid](https://lists.ubuntu.com/archives/ubuntu-devel-announce/2008-July/000460.html) … and it now works like a charm. Thank you very much ! Best regards, Axel ---
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 12, 2008, 4:17am UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/6 "2008-08-12T04:17:20Z")
On Monday 11 August 2008 11:26:44 Charles Oliver N. wrote: > with all the Linux > distros now providing installable OpenJDK-based JVMs, there’s hasn’t > been much interest in getting GCJ to work. Would there be any performance increase? That is: Does GCJ actually compile to binary? Or is it more like a wrapper for some sort of VM? My understanding is, it might at least reduce start time. But that’s probably not a reason to put a huge amount of effort into it. ---
**Author:** ![Axel\_E](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/7c8e57/32.png) [@Axel\_E](https://www.ruby-forum.com/u/Axel_E)\ **Post date:** [August 12, 2008, 11:13am UTC](https://www.ruby-forum.com/t/jruby-and-ubuntu-and-libgcj/145553/7 "2008-08-12T11:13:06Z")
David M. wrote: > My understanding is, it might at least reduce start time. But that’s probably > not a reason to put a huge amount of effort into it. GCJ is generally a lot slower at everything but startup time, because it lacks the ability to do the runtime optimizations that are typically responsible for Java’s best performance. My understanding is that it does compile to something mostly native with a very large runtime library (large as in comparable to what a JVM would be, or perhaps a bit smaller), and that native-compiled code starts up rather fast. But most numbers indicate that when the app is up and going, performance is not as good as, for example, OpenJDK. Like I say, though, we’d welcome someone helping to get JRuby running on GCJ. It did at one point, but as we started to incorporate more Java 5+ features it started to slip away. And with OpenJDK basically making Sun’s HotSpot JVM free AND Free, there’s been almost no demand for GCJ over the past several months. Hell, even Debian has approved OpenJDK for inclusion, and they were dead-set on requiring that all Free Java-based apps be GCJ-compatible for the longest time (keeping JRuby out of the dist for the past year or so). - Charlie