Run icedtea-web using JamVM

[Robert Lougher]

JamVM is a Java Virtual Machine.  It supports both the GNU Classpath
library and the library from OpenJDK.  What you have on Buildroot is
JamVM with GNU Classpath.  The IcedTea project, packages OpenJDK with
additional VMs such as JamVM.  You could also build "vanilla" OpenJDK
and then replace the JVM with JamVM.  Additional information is
contained in JamVM's INSTALL and README files.

Rob.


On 4 October 2014 02:09, Felipe Scarel <fbscarel at gmail.com> wrote:
> This JamVM I was talking about is this project: http://jamvm.sourceforge.net/
> That said, I just checked Buildroot Makefile information for JamVM and
> it uses GNU classpath on build, so that's out the window.
>
> It's pretty clear I'll have to install openjdk-jre on the target
> machine, then. I've successfully compiled the JDK on the host machine
> in a test run, but for obvious size implications I'd like to "make
> install" only the JRE on the target machine. I'll research how to do
> that on OpenJDK docs and mailing lists, but if you have any pointers
> on that (even though not directly related to IcedTea), I'd be
> grateful.
>
> Thanks for the help, Omair. Regards,
> fbscarel
>
> On Fri, Oct 3, 2014 at 5:31 PM, Omair Majid <omajid at redhat.com> wrote:
>> * Felipe Scarel <fbscarel at gmail.com> [2014-10-03 14:48]:
>>> The problem is I used OpenJDK-7 to build the image in my host environment, and
>>> understandably IcedTea won't work on the resulting image, complaining 'java' is
>>> not on the PATH. I have access to JamVM on Buildroot (as this package has
>>> already been made available previously), so my question is: can I use
>>> icedtea-web with JamVM (rather than OpenJDK-JRE)?
>>
>> Can you elaborate what this JamVM is? Is it the JavmVM virtual machine
>> built so that it uses the OpenJDK class libraries?
>>
>> As far as I know, IcedTea-Web has almost no dependencies on the VM
>> itself - it really just expects a working valid JVM. It doesn't really
>> know anything specific about Hotspot. So, in a sense, a move from
>> Hotspot VM to JamVM VM should be invisible.
>>
>> IcedTea-Web does care about the class libraries though. It is designed
>> to work with OpenJDK's class libraries. It uses internal API that's not
>> part of the Java SE specification. It wont work with GNU classpath, for
>> example.
>>
>> Thanks,
>> Omair
>>
>> --
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