Develop Reference

Java SQLite org.sqlite.JDBC classpath broken?

I stumbled upon a weird error while using JDBC sqlite with org.sqlite.JDBC
my code compiles and runs fine on Windows.
But when I tried moving it to Ubuntu it started showing this:
Exception in thread "main" java.lang.ClassNotFoundException: org.sqlite.JDBC
at java.net.URLClassLoader$1.run(URLClassLoader.java:372)
at java.net.URLClassLoader$1.run(URLClassLoader.java:361)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:360)
at java.lang.ClassLoader.loadClass(ClassLoader.java:424)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308)
at java.lang.ClassLoader.loadClass(ClassLoader.java:357)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:259)
at mall.SQLiteJDBC.<init>(SQLiteJDBC.java:27)
at mall.AllegroReader.<init>(AllegroReader.java:33)
at mall.Mall.main(Mall.java:31)
I'm running it with java -classpath "sqlite-jdbc-3.7.2.jar" -jar Mall.jar" and java -classpath "sqlite-jdbc4-3.8.2-SNAPSHOT.jar" -jar Mall.jar
with both versions in the same directory as my jar and I've tried a dozen different options specifying classpath and it behaves exactly the same. I tried openjdk and oracle jdk.
I tried rebuilding it on Ubuntu, changing ant .xmls, changing paths, etc.
I have no idea what is going on. Pls help.
Here is what happens inside my dist directory:
work1#workwork:/var/www/mall/dist$ ls
mall.db Mall.jar Mall.jar.old sqlite-jdbc-3.8.4.3-SNAPSHOT.jar
work1#workwork:/var/www/mall/dist$ java -classpath "sqlite-jdbc-3.8.4.3-SNAPSHOT.jar:Mall.jar" Mall
Error: Could not find or load main class Mall

The classpath is ignored when you use -jar.
You have to either include the dependencies in the jar (or at least have the jar manifest point to them), or run it with -classpath sqlite.jar:Mall.jar the.main.class.
Error: Could not find or load main class Mall.main. all files are there,
my main class comes from Mall.java and is in mall package which
compiles to Mall.jar
So the correct command line is:
java -classpath "sqlite-jdbc-3.8.4.3-SNAPSHOT.jar:Mall.jar" mall.Mall
OP findings
to view the classes in jar use jar tf Mall.jar - from this I got mall/Mall.class meaning my class containing main was mall.Mall
it showed
mall/Mall.class
so I should have used mall.Mall as the class to run (instead of pulling my hair)

After spending over 6 hours total with many failed attempts at running "portable" jar package using classpath and whatnot, after having tried OneJar and jarjar to no avail (ended up with Class file too large!) I decided to write the offending piece of code in PHP.
It proved to be more portable than Java in my case.

What this following error means?

I am running my java program but on executing it gives me following error.
before it was running fine but now it's throwing following error.
I checked my class path, path in environment variable all are correct.
Exception in thread "main" java.lang.UnsatisfiedLinkError: java.util.zip.ZipFile
.open(Ljava/lang/String;IJ)J
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:114)
at java.util.jar.JarFile.<init>(JarFile.java:135)
at java.util.jar.JarFile.<init>(JarFile.java:72)
at sun.misc.URLClassPath$JarLoader.getJarFile(URLClassPath.java:646)
at sun.misc.URLClassPath$JarLoader.access$600(URLClassPath.java:540)
at sun.misc.URLClassPath$JarLoader$1.run(URLClassPath.java:607)
at java.security.AccessController.doPrivileged(Native Method)
at sun.misc.URLClassPath$JarLoader.ensureOpen(URLClassPath.java:599)
at sun.misc.URLClassPath$JarLoader.<init>(URLClassPath.java:583)
at sun.misc.URLClassPath$3.run(URLClassPath.java:333)
at java.security.AccessController.doPrivileged(Native Method)
at sun.misc.URLClassPath.getLoader(URLClassPath.java:322)
at sun.misc.URLClassPath.getLoader(URLClassPath.java:299)
at sun.misc.URLClassPath.getResource(URLClassPath.java:168)
at java.net.URLClassLoader$1.run(URLClassLoader.java:194)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
Could not find the main class: com.sun.tools.javac.Main. Program will exit.

To elaborate on #Peter Lawrey's answer ...
The start of the stacktrace is this:
Exception in thread "main" java.lang.UnsatisfiedLinkError: java.util.zip.ZipFile
.open(Ljava/lang/String;IJ)J
at java.util.zip.ZipFile.open(Native Method)
at java.util.zip.ZipFile.<init>(ZipFile.java:114)
...
The UnsatisfiedLinkError is thrown when you attempt to call a native method that has not been resolved to a method in the corresponding native library. The rest of the message tells us that the method at fault has the signature:
long java.util.zip.ZipFile.open(String, int, long)
and that meshes with the top frame of the stack trace ... and the fact that Java's ZipFile code is known to use a native library for the heavy lifting.
The fact that it has gotten this far means that the JVM has found the native library and loaded it. But apparently, the load didn't resolve this overload of the native open method. That can only mean one thing: that the version of the ZipFile class on the bootclasspath does not match the native library.
We cannot make any definite conclusions about whether this is a JDK or a JRE, but it seems likely that it is a JDK ... unless the OP is trying to call the Java compiler in a strange way. (The "could not find the main class: com.sun.tools.javac.Main" message probably means that the JVM could not load the class ... because of the UnsatisfiedLinkError breakage.)
Either way, JDK versus JRE is not the immediate problem. The real problem is a mismatch between the "rt.jar" on the JVM's bootclasspath, and the native libraries.
The question asks:
how to solve this then?
It depends on what exactly you did to get this error.
What command did you run?
What were the command line options and arguments?
Have you been "messing around" with your JRE / JDK installation?
Are you trying to use the "rt.jar" file from one installation in another one?

It means your rt.jar is for a different version of Java as your JVM.
I would ensure that you don't have a rt.jar in your boot class path and your JRE is installed correctly.
Could not find the main class: com.sun.tools.javac.Main. Program will exit.
When a class fails to load due to some low level error, it reports that the class could not be found.

The reference in the error message about not finding com.sun.tools.javac.Main leads me to believe that this is a program that needs to be run with the JDK rather than just a JRE.

your JRE path is pointing to the JDK path
Solution :
Step 1: Right click the server
Step 2: Click the Run Time Configuration
Step 3: GIVE the JRE path under the JDK.
Solution fixed

classifier4j class not found exception on addMatch() method

i have a strange behaviour when trying to use bayesian classifier class from classifier4j package
basically my code is:
String test_string = "some bla bla web designers in here whatever";
SimpleWordsDataSource wds = new SimpleWordsDataSource();
BayesianClassifier classifier = new BayesianClassifier(wds);
wds.addMatch("Web Design")
Double d = classifier.classify(test_string);
what i'm getting when trying to run this code is:
run:
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/logging/LogFactory
at net.sf.classifier4J.bayesian.WordProbability.calculateProbability(WordProbability.java:167)
at net.sf.classifier4J.bayesian.WordProbability.setMatchingCount(WordProbability.java:138)
at net.sf.classifier4J.bayesian.WordProbability.<init>(WordProbability.java:115)
at net.sf.classifier4J.bayesian.SimpleWordsDataSource.addMatch(SimpleWordsDataSource.java:94)
at tothego_classifier_test.Main.main(Main.java:44)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.logging.LogFactory
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
... 5 more
Java Result: 1
BUILD SUCCESSFUL (total time: 0 seconds)
which is pretty annoying since i've been trying to run a simple hello-world test (as in the website's usage part). I'm on netbeans 6.9 and i've ofc included classifier4j 0.6 jar and optional jar, also have the correct import statements in my main class.
I know Nick Lothian contributes here, so i tought would be good asking!
thanks everybody for efforts

ok i solved the problem, and here we go with a quick howto for everyone:
http://commons.apache.org/logging/download_logging.cgi click on this link and download the binary file
unzip the file you just downloaded
add commons-logging-xxx.jar, commons-logging-adapters.jar, commons-logging-api.jar to your CLASSPATH / project libs (i tried an awful lot, and it only seems to work with the whole jars included)
rebuild and rerun
hope this is helpful :)

Running Java app from inside emacs using JDEE throws NoClassDefFoundError

I have configured JDEE in emacs. But when I try to run any App, it throws NoClassDefFoundError .
Upon compilation, although a class file is created, it only shows the buffer for sometime and then closes it.
The same files if compiled and run from the terminal work perfectly fine.
Also, on this machine I have java-6-openjdk installed. I had configured JDEE on my home computer which has sun java jdk and there are no such problems there.
Other than this, features such as code completion, generation etc work fine.
How do I solve this? Is this due to open jdk ?
I am using a Ubuntu 10.04 desktop.
This is the stack trace
cd /home/vineet/java/KodeJava/src/org/kodeplay/kodejava/
/usr/lib/jvm/java-6-openjdk/bin/java org.kodeplay.kodejava.EmacsTest
Exception in thread "main" java.lang.NoClassDefFoundError: org/kodeplay/kodejava/EmacsTest
Caused by: java.lang.ClassNotFoundException: org.kodeplay.kodejava.EmacsTest
at java.net.URLClassLoader$1.run(URLClassLoader.java:217)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:205)
at java.lang.ClassLoader.loadClass(ClassLoader.java:321)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:294)
at java.lang.ClassLoader.loadClass(ClassLoader.java:266)
Could not find the main class: org.kodeplay.kodejava.EmacsTest. Program will exit.
Process org.kodeplay.kodejava.EmacsTest exited abnormally with code 1
Thanks

something in your config is wrong. you are trying to run from the "/home/vineet/java/KodeJava/src/org/kodeplay/kodejava/" directory, but in order to find your class on the classpath, you should be running from "/home/vineet/java/KodeJava/src/". Probably need to configure the "jde-run-working-directory" variable.

From the question, it sounds as if the JDEE configuration is not complete when it comes to setting up the command to be launched when running the Java App.
If the same Java App can be run from the terminal with no issues, OpenJDK is not causing the trouble, I'd wager.
Perhaps you copied over from the other computer the JDEE configurations and did not adopt them for the new computer that has OpenJDK.

could not find the main class

I'm using the JDK 3.1. I am using XML Publisher. I'm getting this error:
Could not find the main class. Program will exit.
After I click on "OK", I get
Java execution failed. Please check the Java Option in the option dialog

Sounds like you're trying to execute .jar file and there's no Main-Class entry in the manifest file. Other than that obvious point, your question does not give much information for assistance.

Your question is tricky to understand, but I'm guessing that you haven't actually compiled your Java code, or your compiled code isn't on the classpath.
When I try and execute a non-existent class (this would work if there was a MyClass.class on the classpath with a main() method):
paul#paul-laptop:~$ java MyClass
Exception in thread "main" java.lang.NoClassDefFoundError: MyClass
Caused by: java.lang.ClassNotFoundException: MyClass
at java.net.URLClassLoader$1.run(URLClassLoader.java:200)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:188)
at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:252)
at java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
Could not find the main class: MyClass. Program will exit.
Is that what you're seeing? If so:
compile your class with javac if you haven't done so
check that your classpath includes the location of the class
(You can specify the classpath explicitly when you execute the java program using -classpath, check the documentation for details.)

I include this answer as someone who has made an error someone consuming java rather than programming in it would make:
On the command line when executing a JAR file, be sure your line reads
java -jar whatever.jar
instead of
java whatever.jar
Without the -jar you sometimes get the "Could not find the main class" error.

Here are some good answers What does "Could not find or load main class" mean?
But, I will share one possibility I had. I used the JDK1.7 to compile my code and run the jar package using the JDK1.6, the error is:
Could not find the main class. Program will exit.
So, check if the JDK version you used to run your code is lower than that used to compile your code.

Check this website: "Could not find main class" error when previewing BI Publisher for Word. It directly references Java issues with Oracle BI Publisher Plugins for Word.
It basically says that you need to set your Java Home by going to Options in the BI Publisher Tab in the MS Office Ribbon.