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UnsatisfiedLinkError with OpenCV in Tomcat

First of all, I have a basic example of OpenCV running in a main method.
However, if I use OpenCV in a Spring Web Controller, an error is thrown.
I am getting an UnsatisfiedLinkError when running the following code inside a Tomcat Server, within STS (Spring Tool Suite), and have boiled the problem down to the following code:
System.loadLibrary(Core.NATIVE_LIBRARY_NAME);
CascadeClassifier cascadeClassifier = new CascadeClassifier();
The run configurations of both the server and the "main" application contain the VM Arguments pointing to the OpenCV DLLs:
-Djava.library.path="C:\opencv\build\java\x64;C:\opencv\build\x64\vc10\bin"
For reference, I have also included the pertinent bits of the stacktrace below:
org.springframework.web.util.NestedServletException: Handler processing failed;
nested exception is
java.lang.UnsatisfiedLinkError: org.opencv.objdetect.CascadeClassifier.CascadeClassifier_0()J
...
Caused by: java.lang.UnsatisfiedLinkError:
org.opencv.objdetect.CascadeClassifier.CascadeClassifier_0()J
at org.opencv.objdetect.CascadeClassifier.CascadeClassifier_0(Native Method)
at org.opencv.objdetect.CascadeClassifier.<init>(CascadeClassifier.java:38)
at com.immersion.test.controllers.SimpleController.createClassifier(SimpleController.java:19)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
Note: I have read in several StackOverflow threads that the main cause of the UnsatisfiedLinkError is the missing System.loadLibrary(Core.NATIVE_LIBRARY_NAME) call. This is clearly not the case here, since it is being called just above where the exception is thrown.

Same thing here.
I try what Dylan said, but did not work here.
But I added "C:\opencv\build\java\x64;C:\opencv\build\x64\vc10\bin" on my PATH variable. On my sys variables.
ps: I'm using windows.

It turns out that the default run configuration to start a Tomcat server within STS/Eclipse is essentially just a launcher for Tomcat.
This means that any VM Args that are added to the Tomcat 'run configuration' will not be transferred to the actual Tomcat instance.
On looking in tcruntime-instance.bat within the Tomcat directory (this is what ends up creating the tomcat java instance), we can see that simply by adding our intended VM Args to the JAVA_OPTS environment variable, the dlls will be available to Tomcat.
TL;DR:
So.. Simply add the the locations of the OpenCV binaries to your JAVA_OPTS environment variable:
-Djava.library.path="C:\opencv\build\java\x64;C:\opencv\build\x64\vc10\bin"
For more information on setting JAVA_OPTS for Tomcat, see this SO question.

ClassFormatError: 154>, Exception caught in Display class

I am running a midlet application already deployed & run on Nokia S60 sdk. I want to make my app run on every java & symbian device. I tried to run the application on Java_ME_platform_SDK_3.4 but getting an error in the code when i am trying to switch the screen from Login to Home
HomeForm homeForm=new HomeForm(objLoginMidlet, objCommonBean);
Display.getDisplay(objLoginMidlet).setCurrent(homeForm);
Code in Home Form is as follows-
class HomeForm extends Form
{
public HomeForm(LoginMidlet objLoginMidlet,CommonBean objCommonBean)
{
this.objLoginMidlet=objLoginMidlet;
this.objCommonBean=objCommonBean;
setTimer();
initHomeForm();
}
}
My MIDP is set to 2.1. Even I changed it to 2.0 but still getting exception as follows
warning**
*Untrusted user classes must never be put
***on the system class path
TRACE: <at java.lang.Error: ClassFormatError: 154>, Exception caught in Display class
java.lang.Error: ClassFormatError: 154
- java.lang.Class.invoke_verify(), bci=0
- java.lang.Class.initialize(), bci=100
- ezypoint.forms.LoginForm.register(LoginForm.java:202)
- ezypoint.forms.LoginForm.commandAction(LoginForm.java:91)
Even I tried to change compilance level but still exception appears.

I don't know the Nokia S60, but this usually happens on CLDC devices when compiled Java class files are being deployed without having them "preverified". This is an additional build step that is required to run them on embedded JavaME devices. See this StackOverflow question.
If you hava a full-blown development environment, this is usually set up automatically (maybe you need to choos the correect target device). However, if you try to compile the Java files by yourself and then run them on your device, it will crash. In this case, you need to call %YOUR_WTK_HOME%\bin\preverify.exe with your class files (and probably add to your ANT script or similar):
%YOUR_WTK_HOME%\bin\preverify.exe -classpath <your-classpath> -d <your-destination-dir> <your-source-directory>

Failed to load sigar-amd64-winnt: java.lang.NullPointerException

I'm new to sigar and native library programming in java, so maybe it is just a simple problem, but I can't find a result on my own.
I'm using eclipse indigo on a win 7 (64bit) OS. I've taken the following steps:
Add sigar.jar an log4l.jar to the jre6/lib, add the sigar-amd64-winnt.dll (also the files for x86) file to ./Program Files/Java/jre6/lib.
Then I only want to create a new sigar() but get the following exception:
Failed to load sigar-amd64-winnt: java.lang.NullPointerException
org.hyperic.sigar.SigarException: Failed to load sigar-amd64-winnt: java.lang.NullPointerException
at org.hyperic.sigar.Sigar.loadLibrary(Sigar.java:170)
at org.hyperic.sigar.Sigar.<clinit>(Sigar.java:100)
at MemExample.<clinit>(MemExample.java:8)
Exception in thread "main" java.lang.UnsatisfiedLinkError: org.hyperic.sigar.Mem.gather(Lorg/hyperic/sigar/Sigar;)V
at org.hyperic.sigar.Mem.gather(Native Method)
at org.hyperic.sigar.Mem.fetch(Mem.java:30)
at org.hyperic.sigar.Sigar.getMem(Sigar.java:304)
at MemExample.getInformationsAboutMemor
I've already tried to manipulate the VM-Arguments (in Run Config -DJava.library.path="path/of/lib"), to set the native library in the java build path to the path of sigar/lib and to set the Systempath in the program on my own with System.setProperty("path", "-"). All of which are unsuccessful until now.
And step by step I yield to despair.
**Edit:**Is it possible that sigar only works with AMD?
Some friend tried the same code with an AMD processor and win 7 (32b) and it works.
I already look for an answer in the hyperic sigar developer forum, but I can't find any useful tips or answers.

Seems that sigar-amd64-winnt.lib is missing: http://communities.vmware.com/message/1947455#1947455

UnsatisfiedLinkError and NoClassDefFoundError : Running Java Mapscript on Ubuntu 11.10

We have coded and run a dynamic web application using MAPSERVER(Version 6.0.1) on windows platform using Java Technology. Now, there is need of deploying it on Ubuntu 11.10. We have installed Apache Tomcat 6.0, Mapserver 6.0.1, Apache 2.0, and FWTools-2.0.1(As this package contain all required tools for mapserver if I am not wrong, so I didn't feel any other tools to be installed). We have deployed the war file(and put application without) in Apache Tomcat 's Webapps folder. I even got the index page which dont have code related with mapscript api. But while fetching the other servlet with mapscript we are getting following error...
java.lang.UnsatisfiedLinkError: no mapscript in java.library.path
java.lang.ClassLoader.loadLibrary(ClassLoader.java:1681)
java.lang.Runtime.loadLibrary0(Runtime.java:840)
java.lang.System.loadLibrary(System.java:1047)
edu.umn.gis.mapscript.mapscriptJNI.<clinit>(mapscriptJNI.java:23)
edu.umn.gis.mapscript.mapObj.<init>(mapObj.java:283)
Again while refreshing the browser page where the above error was displayed, I got a change,
java.lang.NoClassDefFoundError: Could not initialize class
edu.umn.gis.mapscript.mapscriptJNI
edu.umn.gis.mapscript.mapObj.<init>(mapObj.java:283)
I searched on net about the above problem. But finally blank. Please, provide idea about the above problem.

I'm not going to explain why you're getting the UnsatisfiedLinkError, but instead I'll explain why you are getting the NoClassDefFoundError when you reload the page.
A NoClassDefFoundError with a message Could not initialize class ... is thrown by the JVM when it attempts to initialize a class that it has already tried and failed to initialize.
The first of your two stacktraces contains the line
edu.umn.gis.mapscript.mapscriptJNI.<clinit>(mapscriptJNI.java:23)
The method name <clinit> denotes the static initializer, of the class mapscriptJNI. So, at the point that the UnsatisfiedLinkError was thrown, the JVM was trying to initialize this class. Looking at the error message, it seems that this static initializer tried to load the native code library mapscript but failed.
This UnsatisfiedLinkError causes the mapscriptJNI class to fail to initialize successfully. The JVM keeps a record of all classes that fail to initialize, and if you attempt to initialize one of those classes again, you'll get a NoClassDefFoundError with a message saying that it could not initialize that class.
When you refresh the page, you end up causing the JVM to attempt to initialize the class mapscriptJNI a second time. Of course, this class failed to initialize the previous time. Your second stacktrace contains exactly the error I've described.
In short, the UnsatisfiedLinkError is the real error here. Fix that and the other one will go away.

I would check the following 2 items:
Is the mapscript.jar file on Tomcat or at least your webapp's classpath? (NoClassDefFoundError is your big clue here)
Is the libmapscript.so on either your LD_LIBRARY_PATH or -Djava.library.path? (UnsatisfiedLinkError since the shared object cannot be found)
Try having a look at this post, near the Running Java Mapscript (on Linux) section.
Hope that helps!

RMI with multiple JAR inclusion

I am coding a RMI program with 3 JAR:
RMIServer, contains server-side classes
RMIClient contains client-side classes
RMIResource contains server & client shared content (interfaces, custom exceptions)
To make separate JAR files, I created 3 projects in NetBeans, then I declared the shared Jar in the "Libraries/Build" section of the other 2 projects.
Everything just build-up fine, no error.
But when I try to launch the server through the command-line, which was simple before I had the idea to put the shared files in a distinct JAR, this is suddenly pain in the a**...
Here are a few examples of commands I tried:
Keeping the ClassPath pointing to the server resources, but using dual CodeBase
java -cp ~/NetBeansProjects/RMIServer/dist/RMIServer.jar -Djava.rmi.server.codebase="file:/home/myuser/netbeansprojects/rmiserver/dist/rmiserver.jar file:/home/myuser/netbeansprojects/rmiserver/dist/lib/rmiresource.jar" rmiserver.Shop
Result:
Network exception: java.rmi.ServerException: RemoteException occurred in server thread; nested exception is:
java.rmi.UnmarshalException: error unmarshalling arguments; nested exception is:
java.lang.ClassNotFoundException: rmiresource.BookingManager
...
Using dual ClassPath but keeping the CodeBase pointing to the server resources
java -cp "~/NetBeansProjects/RMIServer/dist/RMIServer.jar;~/NetBeansProjects/RMIServer/dist/lib/RMIResource.jar" -Djava.rmi.server.codebase=file:/home/myuser/netbeansprojects/rmiserver/dist/rmiserver.jar rmiserver.Shop
Result:
Exception in thread "main" java.lang.NoClassDefFoundError: rmiserver/Shop
Caused by: java.lang.ClassNotFoundException: rmiserver.Shop
...
Using dual ClassPath & dual CodeBase
java -cp "~/NetBeansProjects/RMIServer/dist/RMIServer.jar;~/NetBeansProjects/RMIServer/dist/lib/RMIResource.jar" -Djava.rmi.server.codebase="file:/home/myuser/netbeansprojects/rmiserver/dist/rmiserver.jar file:/home/myuser/netbeansprojects/rmiserver/dist/lib/rmiresource.jar" rmiserver.Shop
Result:
Exception in thread "main" java.lang.NoClassDefFoundError: rmiserver/Shop
Caused by: java.lang.ClassNotFoundException: rmiserver.Shop
...
EDIT:
I am working on the local computer, simulating distant connections. Thus I use 'file' protocol and not 'http'.
Am I missing something? Thanks for any help you would provide
I tested out again my 1st solution since it was the most promising:
java -cp ~/NetBeansProjects/RMIServer/dist/RMIServer.jar -Djava.rmi.server.codebase="file:/home/myuser/netbeansprojects/rmiserver/dist/rmiserver.jar file:/home/myuser/netbeansprojects/rmiserver/dist/lib/rmiresource.jar" rmiserver.Shop
It still failed.
Then I tested out on Windows:
Setup the rmiregistry with an empty classpath (and cd to the java/bin directory)
set CLASSPATH=""; export CLASSPATH
start rmiregistry
Launch the server with an equal command as before (moduo the Win env changes)
java -cp c:/NetBeansProjects/RMIServer/dist/RMIServer.jar -Djava.rmi.server.codebase="file:/c:/netbeansprojects/rmiserver/dist/rmiserver.jar file:/c:/netbeansprojects/rmiserver/dist/lib/rmiresource.jar" rmiserver.Shop
And... It worked!
I cleaned-up/rebuilt the solution both on Linux & Windows and it is still not working on Linux and working on Windows... I use the same Netbeans version on both!
Can someone explain that to me? I am using the JDK 6 on Linux & JDK 7 on Windows: would that have an impact?

A file: codebase can't work out of the local machine. You need to use HTTP. You could possibly use a file: URL pointing to a shared directory, such that the URL makes sense at a client, but this won't work outside the LAN.
Unless you are using the codebase feature, the RMI Registry needs access to the shared classes via its classpath: rmiregistry -J-Dclasspath=... It's simpler to use LocateRegistry.createRegistry(), then it's in the same JVM as your remote objects and uses the same classpath of course.