Exporting to Runnable jar with extra native code libraries in eclipse

Question

I am having trouble exporting my java project from eclipse as a jar executable file. My java project uses an external library (its called jri). I have exported the jri.jar file and set the library path for its native library in eclipse, and it works great in development in eclipse. However, when I export it as an executable jar file I get the following error:

Cannot find JRI native library!
Please make sure that the JRI native library is in a directory listed in java.library.path.

I have placed a folder called lib in the same directory as my project's jar; this lib folder contains jri's native library. jri's native library is not in one file but in a folder. This is the same setup I have in eclipse.

The way I am exporting my project in eclipse is

Export...
Java > Runnable JAR file
Copy required libraries into a sub folder next to the generated Jar
Finish

And my folder is organized like this

folder project
  project.jar
  project_lib
    jri.jar
    jri native library folder  

The MANIFEST.MF of my project.jar is:

Manifest-Version: 1.0
Class-Path: . project_lib/jri.jar
Main-Class: index

What I want to achieve is to give another person a folder including project.jar and anything else needed so she/he can run it without needing to install anything else. Thanks so much

Sextuple

If you hate dont use it, dont blame about it. If something goes wrong with eclipse it might be your fault not eclipse. – Ultramontane

Check this similar answer, it migth help. #2702632 – Ultramontane

Did you try adding project_lib/jri_native_library_folder to the manifest.mf classpath? – Lordan

@Lordan I am going to try that now – Sextuple

@Lordan I didnt get any better results, I think it is because the problem is in the library path and not in the class path – Sextuple

What's wrong with using ANT? In the time of your running bounty, you could have written your build.xml file which does what you want. – Calk

Answer 1

Add a script containing something like that:

#!/bin/bash
java -Djava.library.path=project_lib/native/ -jar project_lib/jri.jar

I export some java projects that way.

Darendaresay

Answer 2

This is relatively hard to implement. The solutions I have seen involve extracting the native libraries in the JAR to an OS temp directory and then loading it. I would go for an integrated solution for that. One Jar and Java Class Loader support it, and on the second page you will find links to similar tools.

Spitfire

You're right, as far as I know, Java cannot load JNI libraries (.dll, .so, etc.) from a JAR file. The solutions you mention extract the relevant files at runtime, so that Java can load them. – Albuminate

Answer 3

You can put the libraries inside your jar:

Export...

Java > Runnable JAR file

Package required libraries into generated Jar

Finish

I always export this way. I don't know if it will work in your case, but worth a try.

---

Edit:

See these links:

• Instalation, setup and setting environment properly
• What to do when getting Cannot find JRI native library!

My guess is that this have something to do with LD_LIBRARY_PATH not correctly been set. Or the file wich it is searching for isn't in the path listed.

Catholicism

I have tried that but it doesnt work, remember that the native libraries for the external package is in a folder and the java.library.path need to have access to it. – Sextuple

Answer 4

You know I had the similar problems

Could not extract native JNI library.

all above proposes can't help me. I couldn't stop and start gradle deamon by using follow command:

gradle --stop

I saw that gradle deamon still not stopped in my processes. That's why I kill it in my process and all will be fine :)

Anthrax