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Java .dll files not working in .jar

I'm trying to listen keyboard events in Java by using a third-party library from "net.java.games.input". When I run my code in Eclipse, it works fine. But when I build my project and run the .jar, it does not. The reason I guess, the library needs some .dll files to listen my keyboard and they don't work in .jar.
Here's my code example;
ControllerEnvironment ce = ControllerEnvironment.getDefaultEnvironment();
Controller[] ca = ce.getControllers();
So, what should I do to make this work in a .jar?
Thanks.

You can use System.loadLibrary() to let the JVM loading your dll or System.load() to load file from a specific path:
static {
System.load("PATH/TO/file.dll");
}

so your issue is relative to this
JInput "no jinput-dx8 in java.library.path" Error
You should set java.library.path property to point to the directory
containing native dlls of JInput. You can do it by adding
-Djava.library.path=x (where x is your path) to the command line or to the "VM arguments" field of "Run configurations" dialog in Eclipse.
answered Jan 12 '10 at 19:48
axtavt 198k31421427
you can also at the beginnning of your main do this
System.setProperty("java.library.path", System.getProperty("java.library.path")+";thePathOfYourDll");

Eclipse: Setting an environment variable that references a folder contained in a plugin

I have some Java code that wraps an existing native application and performs the following:
Takes some input from the user
Executes a native application providing as parameters the input taken in step 1
Performs some more operations on the output files produced in step 2
The native application in step 2 requires some dynamic libraries. So, under Run Configurations -> Environment I have set the following variables to reference the libraries.
DYLD_LIBRARY_PATH = ${project_loc}/path/to/libs
DYLD_FALLBACK_LIBRARY_PATH = ${project_loc}/path/to/libs
And so far it all works. Now I have packaged my code and the existing native application as an Eclipse plugin. Whenever I try to run the code inside the plugin I get the following error:
dyld: Library not loaded: libsrcml.dylib
Referenced from: workspace/Project/src/nativeApp
Reason: image not found
To my understanding, this happens because the environment variables I had set previously reference {$project_loc}, which is the location where my Eclipse project was stored. Now, my code is no longer contained in that project, but it is contained inside a plugin, so the path for the variables no longer works. Question is, how can I set a path that references a folder inside my plugin? Alternatively, is it possible to, somehow, load those variables dynamically inside my Java code?

The path variables are used to specify a fixed location in the file system.
To identify a resource in a plugin, I would use its URL
Case 1: Platform.getBundle("").getEntry("")
Bundle bundle = Platform.getBundle("your.bundle.id");
URL url = bundle.getEntry("yourDir/yourFile.txt");
File f = new File(FileLocator.resolve(url).toURI());
Case 2 : Platform URL to your resource:
url = new URL("platform:/plugin/your.bundle.id/yourDir/yourFile.txt");
File f = new File(FileLocator.resolve(url).toURI());
Thanks to Vogella for this tip.
However, for libraries in your plug-in it is a little bit different, as System.loadLibrary("libname") must be able to resolve your lib.
If you ship and use native libraries in your plug-in, please package your plugin as a directory, and not as a compressed jar file.
So edit your plug-in's MANIFEST.MF and set your Eclipse-BundleShape: dir
Eclipse-BundleShape: dir
Then, your plug-in will be packaged as a folder, and then it is your responsibility to make your Native libraries interacting. Usually this depends on how the native libraries are linking each other, and on how your Java-to-native framework is setting the search paths.
My simple solution, is putting all the native libraries to the root folder of the Eclipse executable, which is the Java execution directory, so that I can get that path using the "user.dir" environment variable as follows:
System.getProperty("user.dir");
Then, when all the natives are in the same folder, they can reference each other without problems.
Please, also check these resources:
this StackOverflow answer
this eclipse forum answer

dependency of a JNI DLL which internally calls another dll

I have created a JNI library with visual studio to use in java application and internally this dll calls another DLL (openssl). Now when i load this library with eclipse I get an error saying "Can't find dependent libraries" unless I put the path of the other DLL on the PATH variable.
in thread "main" java.lang.UnsatisfiedLinkError: C:\*****\jniDLL.dll: Can't find dependent libraries
at java.lang.ClassLoader$NativeLibrary.load(Native Method)
at java.lang.ClassLoader.loadLibrary1(ClassLoader.java:1939)
at java.lang.ClassLoader.loadLibrary0(ClassLoader.java:1864)
at java.lang.ClassLoader.loadLibrary(ClassLoader.java:1854)
at java.lang.Runtime.loadLibrary0(Runtime.java:845)
at java.lang.System.loadLibrary(System.java:1084)
at iwinAlgTest.test.<clinit>(test.java:7)
And I've already tried adding it to -Djava.library.path and to the classpath, and i also included all of my dll and openssl dll and lib files like libeay32.lib but neither worked. Is there a way to do this?
I tried to use Dependency Walker to check if there are any files required by my jniDLL.dll
but i get interesting thing:
what i really do to create my jniDLL:
(jniDLL --> calls myDLL.dll) ==> (myDLL.dll --> calls openssl library)
but Dependency Walker says that
(jniDLL --> depends on myDLL.exe) not myDLL.dll
Note : at first it was a win32 application( which output myDLL.exe) but i changed the project setting to output myDLL.dll then i create another project to create a JNI dll from myDLL.dll which i wrote in c++

One way to bypass this is to load your openssl.dll prior to loading myDLL, so myDLL will find the symbols loaded when it tries to initiate .
Other ways to go around this :
add the openssl.dll to PATH (you already mentioned this)
copy openssl in system32 at install time
put openssl in the same folder as your executable path
This however will only work on Windows.
In linux, you will have to change the rpath inside the .so (but I believe this is out of scope).

JPL/SWI Prolog configuration failure

I'm configuring the JPL right now, and wanna work with swi-prolog using java.
I downloaded the newest stable version of SWI-Prolog, which is 6.2.0, and installed in D:\swipl
First, I added the following path to the PATH virable: D:\swipl\bin, which should include all dll files needed.
Then, I added the following path to the CLASSPATH virable: D:swipl\lib\jpl.jar, which should be the jar file needed.
When I tried to run the versions example provided, I got the following error:
Exception in thread "main" java.lang.UnsatisfiedLinkError: jpl.fli.Prolog.thread_self()I
at jpl.fli.Prolog.thread_self(Native Method)
at jpl.Query.open(Query.java:286)
at jpl.Util.textToTerm(Util.java:162)
at jpl.Query.Query1(Query.java:183)
at jpl.Query.<init>(Query.java:176)
at Versions.main(Versions.java:11)
After searching online, I found that many people just get java.lang.UnsatisfiedLinkError: no jpl in java.library.path which is because of the setting for the PATH variable, rather than the error I get here: java.lang.UnsatisfiedLinkError: jpl.fli.Prolog.thread_self()I (and yes, there is a "I" at the end of the line).
Has anyone gotten this error before? I've tried several previous version of SWI-Prolog, but also got other kinds of errors. I'm using Eclipse IDE for Java development -- have I missed anything?

I've sent the problem to the official mailing list (swi-prolog#lists.iai.uni-bonn.de) provided by swi-prolog.org, and luckily someone helped me to prove that there are some problems in the version 6.2.0. We then both tried the version 6.0.2, and it works perfectly. He mentioned that (and I noticed that) there is no swipl.dll in the bin folder of the version 6.2.0, which MAY causes the issue.
I've already reported the issue to the staff via Email, and at least for now, I suggest that people who want to configure JPL should download the version 6.0.2. Three things to remember:
add a new variable SWI_HOME_DIR under system variables in environment variables, and set the path to the place where you installed the SWI-Prolog (Mine is D:\swipl);
Add the path %SWI_HOME_DIR%\bin to your PATH variable, rather than use something like "D:\swipl\bin". (Otherwise [FATAL ERROR: Could not find system resources] will occur)
Add the path %SWI_HOME_DIR%\lib\jpl.jar to your PATH variable, rather than use something like "D:\swipl\lib\jpl.jar". (Otherwise [FATAL ERROR: Could not find system resources] will occur)
If you are using Eclipse for Java development, it seems that you DO NOT need to configure in your IDE. As long as you follow the 3 steps above and add the correct jar file as an external library, it should be fine.
I'm not sure whether the temporary solution works for everyone, but definitely, everyone who has the issue should try this method first. As long as the issue in the version 6.2.0 has been figured out, I'll add some comments here.
BTW, as far as I know, until now, people who have the issue are using 32-bit Windows.

Try adding your path to java.library.path via Run > Run Configuration > [project name] and add the following under "VM Arguments" tab.
-Djava.library.path="D:\swipl\bin;."
Furthermore, under the "Environment" tab, add the following:
VARIABLE: PATH
VALUE: D:\swipl\bin;${env_var:PATH}
After that, go to Project > Properties > Java Build Path, select "Libraries" tab.
Click "Add External JARS.." and find your jpl.jar.

Great Great Great, second answer is the solution
create SWI_HOME_DIR variable to set the swi prolog instalation directory
SWI_HOME_DIR ------- C:\Program Files\swipl
set PATH to point to the library and bin like this
PATH ------ %SWI_HOME_DIR%\bin;%SWI_HOME_DIR%\lib\jpl.jar
This fix my problem "Exception in thread "main" java.lang.UnsatisfiedLinkError: no jpl in java.library.path windows" it is a little bit rare but it works find.

I had the same problem. In addition to set the PATH, you need to verify if the installed SWI program has the same architecture (32 or 64) of your JVM.

how to overcome this exception

i am using a third part SDK with my java application.The providers of sdk provided me exe file that i installed and one java project.I installed the exefile.
Now when i run the code i get a dialog box showing error
Excepting a absulut path for library AKSSDK.dll
No AKSSDK in java.library.path
could not load load library AKSSDK
how do i resolve it?

You need to run java with the following configuration:
java -Djava.library.path={where your library is}
Note the above is the directory where your library is, not the full path name of the library!

You have to add AKSSDK.dll to your PATH environment variable.
It would look like this:
echo %PATH%
C:\xyz\;C:\other\etc\etc;C:\Your\Path\To\AKSSDK.dll
EDIT
To modify your environment variable you have to go to:
MyComputer/RightClick/Properties/Advanced/EnvironmentVariables
(source: vlaurie.com)
And modify the existing Path under System variables
See this tutorial for more details: http://vlaurie.com/computers2/Articles/environment.htm
I have had problems with the white space of ( Program files ) in the past. If possible install your SDK on something like C:\SondaSDK or C:\You\SondaSDK
That way you shouldn't have problems.

You can manually set the path to this value by starting with
java -Djava.library.path=PATH_TO_LIBRARY