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Thread: My program will compile but wont run

  1. #1
    Junior Member
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    Oct 2012
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    Default My program will compile but wont run

    Hey, basically im doing coursework to program a virtual robot to navigate its way through a maze, and im writing the code for this to happen. So, i can compile the code in the context of the maze environment, using javac -classpath maze-environment.jar MyController.java and this compiles fine and will also work okay when i add the resulting .class file to the maze environment and test it. However when i try to run the controller from the Terminal (Im on Mac OSX btw), i get the following error message:

    java -classpath maze-environment.jar MyController.java
    Exception in thread "main" java.lang.NoClassDefFoundError: MyController/java
    Caused by: java.lang.ClassNotFoundException: MyController.java
    at java.net.URLClassLoader$1.run(URLClassLoader.java: 202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.j ava:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:3 06)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launche r.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:2 47)

    Can anyone help me out with this? :/ Any help is much appreciated!

  2. #2
    Crazy Cat Lady KevinWorkman's Avatar
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    Default Re: My program will compile but wont run

    Are you trying to run a jar? If so you need to use the -jar option.

    Are you trying to run a class file? If so you need to drop the .java part of the filename.
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