Exception in thread "main" java.lang.NoClassDefFoundError in my test

Question

I know this has been asked many times but I can't figure it out. :(

I have a big project and the structure is like:

Project - build
        - Config
        - src
        - tst
        - build.xml
        - webapp
        - eclipse-bin

There is a java file under tst/com/myspace/gateway/content/restlet/SanityTest.java In the java file:

package com.myspace.gateway.content.restlet;
...
public class SanityTest extends ContentGatewayRestletResourceTestCase {
...
public static void main() {
}
}

After the whole project compiles, the class file of SanityTest is under build/private/classes/tests/com/myspace/gateway/content/restlet/SanityTest.class

I went into build/private/classes/tests and ran "java -cp . com.myspace.gateway.content.restlet.SanityTest" but got the NoClassDefFoundError.

Please help me!

PS: Stack trace:

Exception in thread "main" java.lang.NoClassDefFoundError: com/myspace/gateway/content/ContentGatewayTestCase
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$000(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)
    at java.lang.ClassLoader.loadClassInternal(Unknown Source)
    at java.lang.ClassLoader.defineClass1(Native Method)
    at java.lang.ClassLoader.defineClass(Unknown Source)
    at java.security.SecureClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.defineClass(Unknown Source)
    at java.net.URLClassLoader.access$000(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)
    at java.lang.ClassLoader.loadClassInternal(Unknown Source)
Caused by: java.lang.ClassNotFoundException:         com.myspace.gateway.content.ContentGatewayTestCase
    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)
    at java.lang.ClassLoader.loadClassInternal(Unknown Source)
    ... 24 more
Could not find the main class: com.myspace.gateway.content.restlet.SanityTest.  Program will exit.

NoClassDefFoundError can happen even if you have the class correctly in classpath. Reason can be failing static code or any othrr exception while classloader tries to load the class — Nitin Dandriyal, May 14 '15 at 07:49
Can you give copy the full error including stack trace into your question? Use the "edit" button please, and properly format it. — RealSkeptic, May 14 '15 at 07:50
Why do you roll back formatting changes? Do you think it looks better unformatted? — Stefan van den Akker, May 14 '15 at 07:57
Be careful where you're running your command line <-cp whatever path> If I were using maven to build my project and say it would put my classes into two separate folders, one called ./classes/ and another ./test-classes/ to run my Main file I would have to somehting of the form: D:\Data\myUser\Documents\NetBeansProjects\DeleteMe\target>java -cp ./classes/;./test-classes/ launcher.Main | Lisbon <--- Program output public class Main { Launcher public static void main(String[] args) { System.out.println(new pt.MostBeautifulCity().getName()); } } — 99Sono, May 14 '15 at 08:05
By the way - I would recommend that you discard the old-school way of building projects in an IDE where you select the "project" nature - jar - war whatever. Eclipse loves that you do that. Just don't! use maven and if the IDE hates maven, discard the IDE. — 99Sono, May 14 '15 at 08:12
The project is built primarily using Ant I think. Looks like com.myspace.gateway.content.ContentGatewayTestCase is missing. I'm looking into that... — StackJay, May 14 '15 at 08:14

score 0 · Answer 1 · edited May 23 '17 at 11:58

You ran

java -cp . com/myspace/gateway/content/restlet/SanityTest

You should have run:

java -cp . com.myspace.gateway.content.restlet.SanityTest

Read this Q&A for more details:

What does "Could not find or load main class" mean?

UPDATE

According to the stacktrace, the problem is that Java cannot find the ContentGatewayTestCase class. Presumably, that is a class that your SanityTest class depends on. However, the source code snippet shows that SanityTest extends ContentGatewayRestletResourceTestCase. You need to figure out if the ContentGatewayTestCase dependency is correct:

If it is, the corresponding ".class" file needs to be in the same directory as your "SanityTest.class" file.
Either way, you probably have a problem with the way you are compiling your code.

I did run java -cp . com.myspace.gateway.content.resetlet.SanityTest. My mistake in the OP, I will update it. — StackJay, May 14 '15 at 07:54

Exception in thread "main" java.lang.NoClassDefFoundError in my test

1 Answers1