From: Michal Suchanek <hramrach@...>
Date: 2010-05-26T06:38:56+09:00
Subject: Re: Ruby one-file launcher that sets up environment?

On 25 May 2010 21:56, Charles Oliver Nutter <headius@headius.com> wrote:
> On Sun, May 23, 2010 at 5:18 PM, Michal Suchanek <hramrach@centrum.cz> wrote:
>> Well, actually it does not.
>>
>> If I wanted to distribute the script in multiple files then
>> distributing it with a launcher would be just fine and would not
>> require the user of the script to have administrative privileges to
>> install the script in a system directory nor the additional knowledge
>> how to make it effective without restarting his session.
>>
>> However, I was aiming for one self-contained example which is easy to
>> distribute so I wanted one file.
>
> You can generally get by using the runtime CLASSPATH in JRuby:
>
> require 'java'
>
> $CLASSPATH << 'somefile.jar'
>
> This doesn't always work, since it's using a child classloader in
> JRuby to handle all the classpath entries, but it often works well
> enough for a simple self-contained app.
>
> Alternatively you can just throw everything in the same jar if there
> aren't file conflicts...
>

The thing is that I do have to set the CLASSPATH for my application to
work, and even set LD_LIBRARY_PATH in some cases, even if everything
is in one jar.

Also setting $CLASSPATH does not work anyway:
java/lang/ClassLoader.java:1649:in `loadLibrary':
java.lang.UnsatisfiedLinkError: Can't load library:
/InsightToolkit.jar must be in CLASSPATH/libSwigRuntimeJava.so
(NativeException)
        from java/lang/Runtime.java:787:in `load0'
        from java/lang/Runtime.java:775:in `load'
        from InsightToolkit/itkbase.java:60:in `<clinit>'
        from InsightToolkit/itkImageFileReader_2DJNI.java:1493:in `<clinit>'
        from InsightToolkit/itkImageFileReaderF2.java:67:in
`itkImageFileReaderF2_New'
        from ./testscript.rb:29

Thanks

Michal