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still experiencing linker error despite linking the java jar file in visual studio code

I am trying to build a small personal project with opencv. I included the path to the opencv jar file in visual studio using the java dependencies then referenced libraries but i get the linker error: Exception in thread "main" java.lang.UnsatisfiedLinkError: no opencv_java430 in java.library.path. I have no idea what else i could do

UnsatisfiedLinkError isn't about jar files.
It's about 'native' files. These are generally stored as a .jnilib file on mac, as a .DLL on windows, and as a .so file on on most unixen.
They cannot be in jar files.
Some libraries will put in some effort and ship a whole bevy of them (as each architecture and OS has a unique dll/jnilib/so file that is needed) inside the jar, will find the 'right' one for your arch/os combo, unpack it someplace, and try to load it live.
This is either not working, or this library isn't doing that. Presumably the opencv site contains a tutorial on how to get it running; as native files are required, it's a bit more involved than 'just download, add to classpath, and voila'. I suggest you follow it precisely.
If you do have something that seems suitable (probably called opencv_java430.dll or whatnot), start java with java -Djava.library.path=/directory/containing/that/file the.rest.of.your.java.args - that should help.

Robocode libraries cannot be found by Robot upon runtime

I have the programming game 'Robocode' in my project root so I can run the project anywhere and not have it installed in C:/robocode. I have a run configuration with the following options;
Main Class: robocode.Robocode
VM Options: -Xmx512M -Dsun.io.useCanonCaches=false -Ddebug=true -DNOSECURITY=true -cp libs/robocode.jar
Working directory: MY_ROOT\robocode_master
JRE: Default(9.0.1 - SDK of my main module)
I'm writing some custom functionality for an AdvancedRobot that connects to a MongoDBAtlas Cluster for necessary data. I'm using mongo-java-driver-3.6.1. The .jar has been added as a library to IntelliJ, then as a compile dependency on the main module. It works fine in testing, I can download documents etc.
To illustrate, the libraries are shown here in the Project structure pane.
I have set the compile output path to the robocode_master/robots directory so that when I run Robocode from IntelliJ, it will see the custom robot .class files in the correct directory and allow me to add them to a battle.
The problem is when I start the battle and the robot tries to do what it needs to do, it throws a java.io.FileNotFoundException and is trying to find the necessary library files from the robocode_master/robots directory.
For example, the first thing it does is connect to the DB;
java.io.FileNotFoundException: MY_ROOT\robocode_master\robots\com\mongodb\MongoClient.class (The system cannot find the path specified)
When I have my project output paths set to the robots folder, upon launching Robocode, it throws a bunch of FileNotFoundExceptions. But if I switch the options to 'Inherit project compile output path', then launch Robocode, I don't get the exceptions upon launch. But now of course, my robots aren't in the default directory, so it can't see them. So I add the new path in out/production/... to Robocode in the GUI and reboot, and I then get the same exceptions from the robots. It now tries to look for the files in out/production/.../com/mongodb/MongoClient.class
How can I 'tell' Robocode to look for the libraries in their default location on the classpath?

Robocode will look for robot classes in your /robots folder. If your robot is located somewhere else, you need to tell Robocode where to locate these from the Robocode UI by setting with the Developments Options. Robocode has it's own class loader for loading Robot classes - but only robot classes.
Other classes/libraries must be specified on the ordinary classpath for Robocode using the -cp or -classpath for the java command (VM Options) like done for any other Java application.
Also notice, that you should use the VM Options that comes with Robocode - like the ones specified in the robocode.bat file. Especially when you use Java 9 or newer:
java -Xmx512M -cp libs/robocode.jar -XX:+IgnoreUnrecognizedVMOptions "--add-opens=java.base/sun.net.www.protocol.jar=ALL-UNNAMED" "--add-opens=java.base/java.lang.reflect=ALL-UNNAMED" "--add-opens=java.desktop/sun.awt=ALL-UNNAMED" robocode.Robocode %*
You could copy this into "run_my_stuff.bat" and add stuff to the -cp right after libs/robocode.jar.
However, I am not sure if it will work with the Mongo driver. Robocode was built for simple robots with limited access to resources like CPU cycles, file access etc.

Exporting a runnable jar, opening it returns an UnsatisfiedLinkError

I currently wrote a simple GUI in Eclipse which runs as intended. I was hoping to export it so I can share it with my friend (who doesn't need to install eclipse and the java libraries). I tried all 3 library handling method Eclipse provides and none of them works. I read a little online and saw something about a manifest file, but wasn't quite sure what to do with it. Is it going to help?
This is where I placed the folder that comes with the .dll file.
This is the result. Am I doing something wrong?

As indicated by the error messages in the first screenshot, what you are missing here is the native library - the software library written and compiled to native code specific to the operating system. What you will need to do is provide the libraries specific to the operating system on which your software will run, eg. dlls for 32 or 64 bit Windows. The manifest does not provide the capability to include those libraries.
When the program is run on Windows, Java will look for native libraries in the following locations:
The current directory
The directories in the PATH environment variable
The directories in java.library.path (if it's specified)
It may be easiest to simply put all files in the one directory. If you do this, you should be able to run the program in the same way as you do now.
The java.library.path option is only needed if you want to put your native library files in a directory separate to the one in which you run your program and not on your PATH. It is only in this case that you will need to add java.library.path, eg. by adding -Djava.library.path=c:\path\to\your\lib after java. Also note that you may use a relative path, ie. a path that is relative to the directory you are in when you execute the command.
I also see from your later error messages that you have another dependency, but on a java library LeapJava.jar. As running a jar with -jar will only work if you have a single jar, but because you have more than one (your own program plus the dependency), you'll instead need to use the -classpath (or -cp for short) argument and add your main class. The classpath argument is a semicolon-separated list of classpath locations, while the main class is the one containing your public static void main method, eg. your.package.name.YourMainClass. So assuming your UI.jar is still in C:\Users\Ian\Desktop\Leap Data UI, you should be able to navigate to that directory and execute with:
java -cp UI.jar;UI_lib\LeapJava.jar -Djava.library.path="UI_lib\x64" your.package.name.YourMainClass

When I package my project into a .jar with eclipse, it can't find lwjgl [duplicate]

I'm making a basic game in Java using the LWJGL Library via Netbeans.
I've created a library with the lwjgl, lwjgl_util, and jinput .jar's, and I added -Djava.library.path=C:\LWJGL\native\windows to the "Run" category in the project's properties.
When I run the file in Netbeans, it runs perfectly with no issue. But when I run the .jar via double-clicking the file, nothing pops up (not even the momentary cmd error window, as far as I can tell). And when I run the file via command line, I get:
C:\Users\200160765>java -jar "C:\Users\200160765\Documents\NetBeansProjects\Game
\dist\Game.jar"
Exception in thread "main" java.lang.UnsatisfiedLinkError: no lwjgl in java.libr
ary.path
at java.lang.ClassLoader.loadLibrary(Unknown Source)
at java.lang.Runtime.loadLibrary0(Unknown Source)
at java.lang.System.loadLibrary(Unknown Source)
at org.lwjgl.Sys$1.run(Sys.java:73)
at java.security.AccessController.doPrivileged(Native Method)
at org.lwjgl.Sys.doLoadLibrary(Sys.java:66)
at org.lwjgl.Sys.loadLibrary(Sys.java:82)
at org.lwjgl.Sys.<clinit>(Sys.java:99)
at org.lwjgl.opengl.Display.<clinit>(Display.java:130)
at game.Draw.createWindow(Draw.java:198)
at game.Draw.init(Draw.java:214)
at game.Draw.run(Draw.java:56)
at game.Main.main(Main.java:9)
I've tried moving the DLL's and .jar library files around to the 'lib' folder in the same directory as Game.jar, and moving them to the same directory as Game.jar, but I get the same error. Could someone help me as to why I can't seem to get this working outside of netbeans?

you have to point the jvm to where the native files are located using a command line parameter -Djava.library.path="path/to/natives". You could use a batch (.bat) file to specify this and start your application for you.
Alternatively you can use a tool like JarSplice to create a single executable jar file from all your jars and at the same time include your native files inside it. It automates the tricky part of specifying the natives manually and provides a nicer end user experience.
To use JarSplice just select your game.jar, lwjgl.jar, lwjgl_util.jar, and jinput.jar in the jars tab. Then all the *.dll, *.so, *.dylib and *.jnilib files in the natives tab. Add your main class on the class tab and create the single executable jar.

LWJGL needs the native components for your particular platform to be in java.library.path. These are in the subdirectory native in the LWJGL distribution and end in .so on Linux, OSX and Solaris and .dll for windows.

When I had this issue, it was because i accidentally put the argument to specify the location of the natives (-Djava.library.path=/native/) in the field called 'Arguments' under the run category of the options panel, instead of 'vm Options'.
As seen here: http://s30.postimg.org/6f90akidt/Capture.png

And yet another way to do this is with Java Web Start (jnlp): http://lwjgl.org/forum/index.php?topic=3763.0
This makes sharing your project easier in some ways.

I had this problem and fixed it using jarSplice (http://ninjacave.com/jarsplice)
make sure you delete all of the preplaced natives in your jar before you create the fat jar, otherwise it will create a duplicate error

I also got the same error and then realised that I named the file "my_lib.zip" instead of "my_lib.jar". Maybe it may help someone.

Another thing to check:
If you are using a 32 bit JVM, you need 32 bit libraries. (Even on a 64 bit OS)
If you are using a 64 bit JVM, you need 64 bit libraries.

Exported Runnable Jar File - I know what's wrong but not how to fix

How to export to runnable java file with eclipse using slick and lwjgl (Light Weight Java Graphics Library)?
So, I have done some research into this and believe I have found the root of the problem and what needs fixing, now I need to figure out how to fix it.
I have a fairly large project that use slick and lwjgl. These are both provided as .jar files that I have added to the java build path in my IDE (Eclipse INDIGO, in case you where wondering).
My goal is to export the piece into a single runnable jar file. Eclipse gives me three options for this:
Extract required libraries into generated JAR
Package required libraries into generated JAR
Copy required into a sub-folder next to the generated JAR
I have been gunning for the second options and it seems the easiest to deal with logically. Anyway when I select this option I press the FINISH option (the only one available to me other than BACK and CANCEL) I get the generation progress popping up for a sec and all seem well. However, if I run the resulting file I get an Unresolved Linker Error as it cannot find lwjgl.
Seeing as both slick.jar and lwgjl.jar are inside the generated JAR when viewed with winRar, I assume that some information is being lost about the java build path when everything goes from the IDE to the runnable JAR.
My research so far seems to suggest I can point the generated JAR to the enclosed files it needs through something in the manifest.txt file but this is were I have been unable to find anything more concrete.
Can anyone please advise me where to go from here?
P.S: I have tried almost every permutation of the export option and environmental options for the build path but when I run the generated JAR it get various differing errors that still all mean "I cannot find this here external".
P.P.S: I forgot to add, eclipse itself is mentioned in the manifest file as follows:
Manifest-Version: 1.0
Rsrc-Class-Path: ./ lwjgl.jar slick.jar
Class-Path: . lwjgl.jar slick.jar
Rsrc-Main-Class: Game.Game
Main-Class: org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader
Every bit of common sense tells me that needs to be changed as it refers to the .jars' location but again, not sure what to or where to begin.

You could use JarSplice, just export the jar from Eclipse, with your classes and resources (don't include any libraries at this point), then use JarSplice to add any libraries and natives (like lwjgl and slick) and make the jar runnable.