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NoClassDefFoundError using bluetooth in java

I asked a question earlier here: NoClassDefFoundError with bluecove's javax.microedition
but got no responses.
I am trying to run some java code (Server.java) that requires bluetooth, so I installed the bluecove-2.1.0.jar file in C:\Program Files\Java.
I compile my code with javac -cp "C:\Program Files\Java\bluecove-2.1.0.jar";. Server.java and run it with java Server -cp "C:\Program Files\Java\bluecove-2.1.0.jar"
It compiles successfully, but when I run it, I get the error:
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.NoClassDefFoundError: javax/microedition/io/Connection
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.privateGetMethodRecursive(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at sun.launcher.LauncherHelper.validateMainClass(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Caused by: java.lang.ClassNotFoundException: javax.microedition.io.Connection
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 7 more
Any ideas where i've gone wrong?
EDIT: Following Minus' answer, to fix the error that followed, I also needed to use a different .jar file which I downloaded from http://snapshot.bluecove.org/distribution/download/2.1.1-SNAPSHOT/2.1.1-SNAPSHOT.63/

The problem is that the .dll is not loaded correctly.
The library should contain a .dll that will be saved on disk and loaded, maybe the program cannot save the .dll to disk or cannot read it.
Extract the .dll and follow bluecove installation instructions on Native Library location.
For example:
Create a directory c:\blue, and a directory blue\lib.
Put the files like this:
C:\blue\Sever.java
C:\blue\Sever.class
C:\blue\[bluecove_native_library].dll
C:\blue\lib\bluecove-2.1.0.jar
Open a cmd (Command Prompt) on c:\blue
Try to run the app like this:
java -cp .;lib\bluecove-2.1.0.jar -Dbluecove.native.resource=false Server
This way you will have both Server.class and bluecove-2.1.0.jar in classpath and the DLL in path (since on Windows the current dir is in path).

Add a current folder to a classpath (.;) and make sure that your code is in a package-name folder.
So if your server has a package name :
mypackage
make sure that your class code is in a /mypackage directory
than go to a parent folder to /mypackage and call:
java -cp ".;C:\Program Files\Java\bluecove-2.1.0.jar" mypackage.Server

Problems exporting Jar using Weka

i've got a big problem exporting my project as a jar file (inside my project i use weka). I'm using Eclipse.
I've added in Java Build Path weka.jar and i've attached to it weka-src.jar, testing my classifier under eclipse everything works, so i've decided to create a jar (because i need that another program use it).
First of all i've created the manifest file:
Manifest-Version: 1.0
Rsrc-Class-Path: ./ weka.jar weka-src.jar
Class-Path: .
Rsrc-Main-Class: start.Home
Main-Class: start.Home
The main class of the program is Home (inside the package start), while weka.jar and weka-src.jar are inside the /src/ directory of the eclipse program.
When i try to execute the jar created i receive this output:
Error: A JNI error has occurred, please check your installation and try again
Exception in thread "main" java.lang.NoClassDefFoundError: weka/classifiers/Classifier
at java.lang.Class.getDeclaredMethods0(Native Method)
at java.lang.Class.privateGetDeclaredMethods(Unknown Source)
at java.lang.Class.privateGetMethodRecursive(Unknown Source)
at java.lang.Class.getMethod0(Unknown Source)
at java.lang.Class.getMethod(Unknown Source)
at sun.launcher.LauncherHelper.validateMainClass(Unknown Source)
at sun.launcher.LauncherHelper.checkAndLoadMain(Unknown Source)
Caused by: java.lang.ClassNotFoundException: weka.classifiers.Classifier
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 7 more
I think that the problem is the CLASSPATH so i've tried to solve it in this way:
I've created the Environment Variable CLASSPATH with this values:
C:\Users\tomma\Desktop\workspace Eclipse\AndroidPermissionsClassifier\src\weka.jar
C:\Users\tomma\Desktop\workspace Eclipse\AndroidPermissionsClassifier\src\weka-src.jar
but nothing changed, can someone help me please?

You are right: the classpath is the problem. Did you remove the items from the manifest classpath when you added them to the environment CLASSPATH? (Side note: place the source jar in the -sourcepath, not the classpath.)

NoSuchFileException when running jar file

When I run a jar file that accesses other files in the src directory, I get the following RuntimeException:
Exception in thread "main" java.nio.file.NoSuchFileException:
src\FileToBeAccessed.txt.lck
at sun.nio.fs.WindowsException.translateToIOException(Unknown Source)
at sun.nio.fs.WindowsException.rethrowAsIOException(Unknown Source)
at sun.nio.fs.WindowsException.rethrowAsIOException(Unknown Source)
at sun.nio.fs.WindowsFileSystemProvider.newFileChannel(Unknown Source)
at java.nio.channels.FileChannel.open(Unknown Source)
at java.nio.channels.FileChannel.open(Unknown Source)
at java.util.logging.FileHandler.openFiles(Unknown Source)
at java.util.logging.FileHandler.(Unknown Source)
at Program.main(Program.java:30)
The code works fine when I run it directly without building a jar file.

You'll need to change how you access resources in a jar to a stream.
this.getClass().getResourceAsStream("/file.txt");

The correct way is
this.getClass().getResourceAsStream("file.txt");

It is really strange that
this.getClass().getResource("file.txt")
does work in IDE but NOT when you run it from a jar.
this.getClass().getResourceAsStream("file.txt")
works both inside IDE and from jar.

UnsatisifiedLinkError - Any idea on how to fix this?

Exception in thread "main" java.lang.reflect.InvocationTargetException
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(Unknown Source)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(Unknown Source)
at java.lang.reflect.Method.invoke(Unknown Source)
at org.eclipse.jdt.internal.jarinjarloader.JarRsrcLoader.main(JarRsrcLoader.java:58)
Caused by: com.melloware.jintellitype.JIntellitypeException: Could not load JIntellitype.dll from local file system or from inside JAR
at com.melloware.jintellitype.JIntellitype.<init>(JIntellitype.java:114)
at com.melloware.jintellitype.JIntellitype.getInstance(JIntellitype.java:174)
at CaptureScreen.registerHotkeys(CaptureScreen.java:163)
at CaptureScreen.<init>(CaptureScreen.java:100)
at CaptureScreen.main(CaptureScreen.java:199)
... 5 more
Caused by: java.lang.UnsatisfiedLinkError: C:\Users\B\AppData\Local\Temp: Can't find dependent libraries
at java.lang.ClassLoader$NativeLibrary.load(Native Method)
at java.lang.ClassLoader.loadLibrary0(Unknown Source)
at java.lang.ClassLoader.loadLibrary(Unknown Source)
at java.lang.Runtime.load0(Unknown Source)
at java.lang.System.load(Unknown Source)
at com.melloware.jintellitype.JIntellitype.<init>(JIntellitype.java:99)
... 9 more
I get this error when I run from the command line, however, it does not cause any issues with my program running on my machine, however, on other peoples machines the program will not run at all.
I have never come across this error before and fairly confused.. mostly that it runs fine on my machine, but not on others even though it throws this error on both.

This is a classpath error. Its likely that you have it set up right for compile time but not runtime. Make sure that either your jar is in the right location and/or that you've set your classpath to include the jar.

Go to the Jintellitype website, download the source, add it to your download folder and then move the .dll files into the folder with the Jitellitype classes after building the project

Java - Library path error

I'm trying to start my java game but I have some troubles with the java command line:
Here is what I type:
C:\>java -Djava.library.path=%cd%\lib -jar game.jar
And here is what I got:
Exception in thread "main" java.lang.NoClassDefFoundError: org/lwjgl/LWJGLException
at com.game.Main.main(Main.java:7)
Caused by: java.lang.ClassNotFoundException: org.lwjgl.LWJGLException
at java.net.URLClassLoader$1.run(Unknown Source)
at java.net.URLClassLoader$1.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
at java.lang.ClassLoader.loadClass(Unknown Source)
... 1 more
I can start my game with Eclipse (With Run as Java Application) but after the menu I got the following error:
Exception in thread "Thread-5" java.lang.UnsatisfiedLinkError: no lwjgl in java.library.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:72)
at java.security.AccessController.doPrivileged(Native Method)
at org.lwjgl.Sys.doLoadLibrary(Sys.java:65)
at org.lwjgl.Sys.loadLibrary(Sys.java:81)
at org.lwjgl.Sys.<clinit>(Sys.java:98)
at org.lwjgl.opengl.Display.<clinit>(Display.java:129)
at com.game.displaygui.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)
lwjgl.jar has been put into the folder \lib.
Could you explain me with I got that?
Thanks.

This because lwjgl library is made by two components:
the .jar file which contains Java code
and the native binary library (which can be .so or .dll or .dylib according to your OS)
The first error you are getting is because you are setting the library path, that should contain the native library, but it does contain the .jar. So you get a java.lang.NoClassDefFoundError because you should set either the library path to the folder that contains native library, either the classpath to contain the real lwjgl.jar file.
The second error that you get with Eclipse is a successive step: your classpath contains the jar library but it is not able to find the native library attached to it, you can fix it in the following way:

You should specify explicitly which lib files to include (seperated by ;) :
-cp %cd%\lib\lwjdl.jar;%cd%\lib\<another-lib>.jar
Don't be tempted to use the wildcard * as it will cause more harm than good (from previous experience :))

You use the java.library.path option to specify the location of native libraries to load. In the location pointed to by that option you would place all dll or .so files required by LWJGL. On the other hand, you need to make sure that all required JAR files are on your classpath, via the -classpath option. Currently, you have your JAR files in the wrong directory.

In Eclipse, if you using maven.
Add the following to the project "Run" : "VM options" .
-Djava.library.path=yourpath/youproject/java/target/natives