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ClassNotFoundException vs NoClassDefFoundError

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ClassNotFoundException vs NoClassDefFoundError

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I got a NoClassDefFoundError and I tried to remember the difference between this error and ClassNotFoundException. Unfortunately, I was not able to get the difference so I googled and got the following links:

- http://www.jroller.com/sjivan/entry/difference_between_classnotfoundexception_and_noclassdeffounderror

- http://javafanatics.blogspot.com/2007/03/noclassdeffounderror-vs.html 

  • NoClassDefFoundError is the result of the futile implicit load of the
    class (Class1). Meaning the system classloader is trying to load the
    class Class1 due to inherent call by Class2 (may be an inheritance or
    composition there).
  • ClassNotFoundException comes up when there is an explicit load, using ClassLoader.loadClass, Class.forName etc.

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