IOException when loading a native library inside an OSGI bundle using jna.library.path

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What steps will reproduce the problem?
1. Create an OSGi bundle that uses a jnaerated CustomLibrary.INSTANCE
2. Run OSGi container with path to native library (-Djna.library.path=lib)
3. Deploy and start the custom bundle

What is the expected output? What do you see instead?
The JNAerated code should run without problem as according to the documentation 
jna.library.path is where libraries are looked for at run-time. Instead an 
IOException is thrown by the call LibraryExtractor.getLibraryPath()

What version of the product are you using? On what operating system?
maven-jnaerator-plugin 0.9.5 on Windows 7

Is the problem still present in the latest SVN version ?
Yes

Workaround:
Instead of defining jna.library.path, set library.custom
-Dlibrary.custom=lib\custom.dll
This tricks LibraryExtractor.getLibraryPath() 

Stack trace of the Exception:
ERROR: Failed to extract library mOcrApi
java.io.IOException: Cannot list contents of bundle://5.0:1/libraries/win32
        at com.ochafik.net.URLUtils.listFiles(URLUtils.java:58)
        at com.ochafik.lang.jnaerator.runtime.LibraryExtractor.getLibraryPath(Li
braryExtractor.java:96)
        at xx.CustomLibrary.<clinit>(CustomLibrary.jav
a:18)
        at xx.CustomDriver.<clinit>(CustomDriver.java
:16)
        at xx.CustomBundleActivator.start(CustomBundleActivator
eActivator.java:12)
        at org.apache.felix.framework.util.SecureAction.startActivator(SecureAct
ion.java:633)
        at org.apache.felix.framework.Felix.activateBundle(Felix.java:1822)
        at org.apache.felix.framework.Felix.startBundle(Felix.java:1739)
        at org.apache.felix.framework.Felix.setActiveStartLevel(Felix.java:1143)

        at org.apache.felix.framework.StartLevelImpl.run(StartLevelImpl.java:264
)
        at java.lang.Thread.run(Unknown Source)

Original issue reported on code.google.com by A.Kambu...@gmail.com on 30 Nov 2010 at 3:21

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[deleted comment]

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Hello Aleksandar,

Thank you for your report (and for the workaround !).
(EDIT: deleted a silly comment of mine, didn't realize that library.custom is 
JNAerator's own library location override mechanism... this tells you how often 
I use this hack ;-))

Would you have any pointer to an OSGI bundle-howto, so that I can reproduce the 
issue and play a bit ?

Cheers
--
Olivier

Original comment by olivier.chafik@gmail.com on 30 Nov 2010 at 4:08

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Salut Olivier,

As seen in my case, I use Apache Felix. To use it as an OSGi container you can 
get starting information from this page:
http://felix.apache.org/site/apache-felix-framework-usage-documentation.html

Here is a 5-step quick guide:

1. Download Felix Framework Distribution 3.0.6:
http://felix.apache.org/site/downloads.html

2. If you're using Maven, create a test project and do the following to your 
POM:

Add a dependency to OSGi:
            <dependency>
                <groupId>org.apache.felix</groupId>
                <artifactId>org.osgi.core</artifactId>
                <version>1.4.0</version>
            </dependency>

Set packaging to bundle:
<packaging>bundle</packaging>

Create and configure a bundle activator:
            <plugin>
                <groupId>org.apache.felix</groupId>
                <artifactId>maven-bundle-plugin</artifactId>
                <extensions>true</extensions>
                <configuration>
                    <instructions>
                        <Bundle-Activator>xx.CustomBundleActivator</Bundle-Activator>
                    </instructions>
                </configuration>
            </plugin>

3. Inside the start() method of your CustomBundleActivator (implementation of 
org.osgi.framework.BundleActivator), use the Custom.INSTANCE field to include 
the JNAerator magic in the mix.

4. Put your bundle in Felix' bundle/ directory

5. Run Felix:
java -jar bin/felix.jar

Hope that helps,
Alex

Original comment by A.Kambu...@gmail.com on 1 Dec 2010 at 7:10

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btw Here is the code by JNAerator:
    public static final java.lang.String JNA_LIBRARY_NAME = LibraryExtractor.getLibraryPath("Custom", true, xx.CustomLibrary.class);
    public static final NativeLibrary JNA_NATIVE_LIB = NativeLibrary.getInstance(xx.CustomLibrary.JNA_LIBRARY_NAME, com.ochafik.lang.jnaerator.runtime.MangledFunctionMapper.DEFAULT_OPTIONS);
    public static final CustomLibrary INSTANCE = (CustomLibrary)Native.loadLibrary(xx.CustomLibrary.JNA_LIBRARY_NAME, xx.CustomLibrary.class, com.ochafik.lang.jnaerator.runtime.MangledFunctionMapper.DEFAULT_OPTIONS);

I didn't understand why it's different from your example:
http://code.google.com/p/jnaerator/wiki/SimpleMeaningfulExample

public TestLibrary INSTANCE = 
(TestLibrary)com.sun.jna.Native.loadLibrary("test", TestLibrary.class);

I tried different command line options but I couldn't remove the call to 
LibraryExtractor.getLibraryPath(). Maybe only -skipLibraryInstance, but I don't 
like it as a solution because then I'll have to write stuff in my code.

Original comment by A.Kambu...@gmail.com on 1 Dec 2010 at 7:34

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Hi,

The workaround mentioned in the initial report does not work for me. I don't 
even use jna.library.path at all: because my native libraries have other 
dependencies, I set the LD_LIBRARY_PATH environment variable instead. It 
doesn't seem to make any difference if I set jna.library.path or library.custom 
at all.

I now use -skipLibraryInstance while generating the code, and lose the 
getLibraryPath call in my own code. Maybe not so clean, but it works for me.

By the way, I use JNAerator for some Eclipse plug-ins which need to access 
native libraries. Eclipse is also OSGi based, which is why this issue shows up 
for me.

Original comment by tim.slec...@gmail.com on 7 Jun 2011 at 9:10

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Hi,
This issue moved to Github :
https://github.com/ochafik/nativelibs4java/issues/153

Thanks for not updating this page anymore and adding further comments on Github.
Cheers
--
zOlive

Original comment by olivier.chafik@gmail.com on 1 Sep 2011 at 7:26

• Changed state: MigratedToGitHub