How to solve "Symbol lookup error" by using JPL on Ubuntu11.04?

Question

I'm coding a program in Java and I would like to connect to Prolog. Thus, I decided to use JPL. It is perfectly to use JPL on Windows Vista. Later, I have to change the OS platform to be Ubuntu 11.04. Unfortunately, there is an error:

symbol lookup error: /usr/lib/swi-prolog/lib/i386/libjpl.so: undefined symbol: PL_is_initialised

Environment:

1. Ubuntu 11.04
2. Java version 1.6.0_24
3. Eclipse Galileo Version: 3.5.2
4. SWI-Prolog version 5.10.1 for i386
5. Jpl (apt-get install swi-prolog-java)
6. Family.java + family.pl

I explain steps of working and problems as follows. step1: Install swi-prolog + jpl using Synaptic Package Manager

step2: Run Family.java , found an error

step3: Configure the library path at VMarguments step4: Run again, there is an error /usr/lib/jvm/java-6-sun-1.6.0.24/bin/java: symbol lookup error: /usr/lib/swi-prolog/lib/i386/libjpl.so: undefined symbol: PL_is_initialised step5: I also config the environment but the error still the same.

The method that I used to solve the problem as in step 3 and 5 I searched from the internet. I can not find other solutions to try. Does anyone have any idea?
Thanks in advance.

Answer 1

You have to config the LD_LIBRARY_PATH, I think. Try to add the location of the so-library file. And make sure, your System.loadLibrary(); call is relative.

Answer 2

Thank you very much for every supports. Now,i can manage this problem. I found a suggestion from page http://code.google.com/p/javanaproche/wiki/HowToJPL

Following the instructions, i change the swi-prolog version to be a building form source pl-5.10.1. Finally, it works. I think the problem happens because the swi-prolog getting from synaptic manager doesn't set to be a shared library. If anyone knows how to set a share library , it might be work.