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PONoClassDefFoundError thrown when specifying same jar file at compile and run time
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  1. PONoClassDefFoundError thrown when specifying same jar file at compile and run time
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    copied!<p>Hi I'm trying to use an external Java package from my own code and keep getting <code>NoClassDefFoundError</code> even though I am using the same class path that I compiled with.</p> <p>For your amusement I have included a bare bones reproduction of what will undoubtedly be a dumb mistake on my part (I've been at this for about 6 hours so far)</p> <pre><code>/* WTF/WTF.java */ import foo.Bar; class WTF { public static void main(String[] args) { Bar dontCare = new Bar(); } } /* WTF/foo/Bar.java */ package foo; class Bar { public Bar() {} } </code></pre> <p>Now from the WTF directory I run the following:</p> <pre> javac foo/Bar.java [ok] javac WTF.java [ok] java WTF [ok] jar cf foo.jar foo [ok] </pre> <p>I remove the WTF/foo directory so there is only WTF/foo.jar available.</p> <pre> javac WTF.java -cp foo.jar [ok] java WTF -cp foo.jar [$!@#$!] </pre> <pre> Exception in thread "main" java.lang.NoClassDefFoundError: foo/Bar at WTF.main(WTF.java:7) Caused by: java.lang.ClassNotFoundException: foo.Bar 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) </pre> <p>Any clues greatly appreciated!</p>
 

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