I use JNA to load a c++ library (.so) in a java project. I package my library inside the jar, and load it from the jar when instantiating the java class that uses it. I do all this like so:
mvn install compiles the c++ code and packages the outcome dynamic library inside the jar.
I call in a static context when instantiating the LibraryWrapperClass the following
System.load( temp.getAbsolutePath() );
where temp is a temporary file containing the library which was found in the jar. This code is based on the work found here adamheinrich
- I call Native.loadLibrary(LIBRARYPATH) to wrap the library into a java class.
private interface Wrapper extends Library {
Wrapper INSTANCE = Native.loadLibrary( C_LIBRARY_PATH, Wrapper.class );
Pointer Constructor();
...
}
I run tests and validate that the library was found and up and running.
I use a java web project that depends on this project. It uses tomcat and runs fine in local.
My issue is that when I deploy on the server, the LibraryWrapperClass cannot instantiate. Error on server is:
java.lang.NoClassDefFoundError: Could not initialize class pacakgeName.LibraryWrapperClass
at java.base/java.lang.Class.forName0(Native Method)
at java.base/java.lang.Class.forName(Class.java:375)
at org.hibernate.annotations.common.util.StandardClassLoaderDelegateImpl.classForName(StandardClassLoaderDelegateImpl.java:57)
at org.hibernate.boot.internal.MetadataBuilderImpl$MetadataBuildingOptionsImpl$4.classForName(MetadataBuilderImpl.java:758)
at org.hibernate.annotations.common.reflection.java.JavaReflectionManager.classForName(JavaReflectionManager.java:144)
at...
This error seems that the library is found, since there is not the UnsatisfiedLinkError exception thrown. But something else is failing. Do someone know what could happen? How could I debug?
I recall that everything works perfectly in local.
How could I debug?
1. with strace
strace will give you what files Tomcat is trying to open : strace -f -e trace=file -o log.txt bin/startup.sh
After this, look for packageName in log.txt, or other files not found with :
egrep ' open.*No such file' log.txt
2. with JConsole
Enable JMX, launch a JConsole, go to VM summary tab, and check/compare very carefully VM arguments/classpath/library path/boot class path
3. dependency listing with ldd
If a dependency issue is likely to be the problem, the ldd sharedLibraryFile.so command lists all the dependencies and allows to track which one might be missing.
I'm really new to maven and storm so I'm trying to follow the instructions in https://github.com/apache/storm/tree/master/examples/storm-starter. My current path is /home/luc/theTest/storm/examples/storm-starter. Inside the target folder there is a storm-starter-2.0.0-SNAPSHOT.jar file. I'm getting stuck when running
storm jar target/storm-starter-*.jar org.apache.storm.starter.ExclamationTopology -local
I get this error
ionTopology -local
Running: /usr/lib/jvm/java-8-openjdk-amd64/bin/java -client -Ddaemon.name= -Dstorm.options= -Dstorm.home=/home/luc/stormTest/apache-storm-1.1.1 -Dstorm.log.dir=/home/luc/stormTest/apache-storm-1.1.1/logs -Djava.library.path=/usr/local/lib:/opt/local/lib:/usr/lib -Dstorm.conf.file= -cp /home/luc/stormTest/apache-storm-1.1.1/lib/servlet-api-2.5.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/slf4j-api-1.7.21.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/objenesis-2.1.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/kryo-3.0.3.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/log4j-core-2.8.2.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/log4j-over-slf4j-1.6.6.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/storm-core-1.1.1.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/log4j-slf4j-impl-2.8.2.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/minlog-1.3.0.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/log4j-api-2.8.2.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/clojure-1.7.0.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/ring-cors-0.1.5.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/asm-5.0.3.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/reflectasm-1.10.1.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/disruptor-3.3.2.jar:/home/luc/stormTest/apache-storm-1.1.1/lib/storm-rename-hack-1.1.1.jar:target/storm-starter-2.0.0-SNAPSHOT.jar:/home/luc/stormTest/apache-storm-1.1.1/conf:/home/luc/stormTest/apache-storm-1.1.1/bin -Dstorm.jar=target/storm-starter-2.0.0-SNAPSHOT.jar -Dstorm.dependency.jars= -Dstorm.dependency.artifacts={} org.apache.storm.starter.ExclamationTopology -local
Error: Could not find or load main class org.apache.storm.starter.ExclamationTopology
Am I doing something wrong? I'm also a bit confused on whether I have to run the nimbus and supervisor first. I tried with and without them and neither worked anyways. Been searching the web but nothing works. Not sure what else to try.
This is usually caused by inconsistent versions of storm-client and storm-starter. Try following these steps to get the example working.
download the latest release from http://storm.apache.org/downloads.html
in this example, we will use version 1.1.1
extract this to a folder, lets call it ${STORM_HOME}
cd into ${STORM_HOME}/examples/storm-starter
execute mvn package -DskipTests=true
this should build the storm-starter jar in target folder
${STORM_HOME}/examples/storm-starter/target/storm-starter-1.1.1.jar
run the example from ${STORM_HOME} directory:
./bin/storm jar examples/storm-starter/target/storm-starter-1.1.1.jar org.apache.storm.starter.ExclamationTopology
don't add the -local flag since it seems like the ExclamationTopology is only deployed in a LocalCluster if no args are passed. You can check the source code here: ${STORM_HOME}/examples/storm-starter/src/jvm/org/apache/storm/starter/ExclamationTopology.java
I have a problem while trying executing my java application.
Whenever I try to execute the program through the command
java ProgAudioJ
I get this error:
Exception in thread "main"
java.lang.NoClassDefFoundError: ProgAudioJ (wrong name: es_2011/ProgAudioJ)
at java.lang.ClassLoader.defineClass1(NativeMethod)
at java.lang.ClassLoader.defineClassCond(ClassLoader.java:632)
at java.lang.ClassLoader.defineClass(ClassLoader.java:616)
at java.security.SecureClassLoader.defineClass(SecureClassLoader.java:141)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:283)
at java.net.URLClassLoader.access$000(URLClassLoader.java:58)
at java.net.URLClassLoader$1.run(URLClassLoader.java:197)
at java.security.AccessController.doPrivileged(NativeMethod)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: ProgAudioJ. Program will exit.
If I remove from my code:
package es_2011;
Everything works perfectly. How do I solve the problem?
Because I found these answers unclear, here is what you need to do.
First, if you package your code (IE your classes have the package keyword at the top) the compiled classes have to be in a directory with the same name as your package declaration in code. After you have compiled your classes, you need to move up a directory when you exectute the java command, and you include the name of the package. For example, if your code exists in /myFolder/myPackage/ , and your class starts with package myPackage (note that the directory and the package are the same name), then you would do the following (linux / osx):
cd /myFolder/myPackage
javac MyClass.java
cd ..
java myPackage.MyClass
Edit - A late edit to clarify something I see people get confused on. In the example above, the package is only one deep, meaning its just myPackage. If you code has a larger package, like
package com.somedomain.someproject;
you will need to execute the java command from the directory which contains the root directory for that package. For example if your compiled code is in myCode/com/somedomain/someproject/MyMainClass.class, then you will execute the java command from the myCode folder, like this (Again, take special note that the directory structure is the same as the package declaration):
cd /myCode
java com.somedomain.someproject.MyMainClass
Try using:
java es_2011.ProgAudioJ
(instead of java ProgAudioJ).
I'm making some assumptions here about your current working directory and your CLASSPATH. If you can provide information about the command you're running (e.g. what directory you're in, where the class file is located, etc.), we can help you more efficiently.
Try this (compile and run):
dir
2011-02-10 00:30 <DIR> .
2011-02-10 00:30 <DIR> ..
2011-02-10 00:27 58 es_2011
javac es_2011/ProgAudioJ
java es_2011.ProgAudioJ
It's quite clearly stated there:
java.lang.NoClassDefFoundError: ProgAudioJ (wrong name: es_2011/ProgAudioJ)
If you want to put a class in a package(*), then the source code must be placed in a corresponding directory, e.g.,
src/Main.java <- root package (no declaration)
src/es_2011/ProgAudioJ.java <- package es_2011;
(*) You should do it always, except for tiny throw-away stuff and possibly for the main class.
Try this,
Compile your class using below command
$ javac ProgAudioJ.java -d .
Run your application by command
$ java es_2011.ProgAudioJ
The reason that it works when you remove
package es_2011
is that you are changing how the compiler packages up, and effectively locates, the file.
I had the same problem - and the error message wrong name: does indeed point you to the answer. You are using the wrong name "ProgAudioJ" in order to run the .class file.
It has been packaged up as
es_2011/ProgAudioJ
In order to run it - you have to either move up a directory:
If you are here: (Windows)
src\es_2011\
move to
src\
Then run the line:
java es_2011.ProgAudioJ
This tells the compiler to look for the ProgAudioJ - which resides in the es_2011 package. For a standard installation, this will be based on folders - so it will look for the es_2011 folder first, and then the name of the .class file that you want to run (ProgAudio).
I am getting this exception error at
Exception in thread "main" java.lang.NoClassDefFoundError:
org/apache/commons/math3/random/RandomDataImpl
at this line of code:
randomData_ = new RandomDataImpl();
and this is how the class is imported in the code :
import org.apache.commons.math3.random.RandomDataImpl;
i have added all of the math common classes to the classpath while running the code. any ideas whats going on ?
It looks like you did not set the appropriate classpath.
You can set it as follows:
java -classpath lib/*.jar:. mypackage.MyClass
Try that and I am sure it will work.
If you are using maven, then read this article
You can also check your current classpath with:
System.getProperty("java.class.path")
Just write simple app printing this property out and run it just as you run an app with which you are having problems.
I am using command line to run java file. Here's my files:
Class files: workspace/test/src/test/test.class
Java files: workspace/test/src/test/test.java
My command line is (CLASSPATH is already setted):
D:\Twitter\workspace\test\src\test>java test
And my error is:
Exception in thread "main" java.lang.NoClassDefFoundError: test (wrong name: tes
t/test)
Anyone know how to solve this?
You have to provide the fully qualified class name (FQCN) to the java command. Your class is named test (Test as a class name would be better) and is in the package test. Therefore the FQCN is test.test.
To start your program you have to call java test.test. from D:\Twitter\workspace\test\src.
Try:
D:\Twitter\workspace\test\src\test>cd ..
D:\Twitter\workspace\test\src>java test.test