public class ClassNotFoundException extends ReflectiveOperationException
forName method in class Class.
 findSystemClass method in class
     ClassLoader .
 loadClass method in class ClassLoader.
 but no definition for the class with the specified name could be found.
As of release 1.4, this exception has been retrofitted to conform to
 the general purpose exception-chaining mechanism.  The "optional exception
 that was raised while loading the class" that may be provided at
 construction time and accessed via the getException() method is
 now known as the cause, and may be accessed via the Throwable.getCause() method, as well as the aforementioned "legacy method."
| Constructor | Description | 
|---|---|
| ClassNotFoundException() | Constructs a  ClassNotFoundExceptionwith no detail message. | 
| ClassNotFoundException(String s) | Constructs a  ClassNotFoundExceptionwith the
 specified detail message. | 
| ClassNotFoundException(String s,
                      Throwable ex) | Constructs a  ClassNotFoundExceptionwith the
 specified detail message and optional exception that was
 raised while loading the class. | 
| Modifier and Type | Method | Description | 
|---|---|---|
| Throwable | getCause() | Returns the cause of this exception (the exception that was raised
 if an error occurred while attempting to load the class; otherwise
 null). | 
| Throwable | getException() | Returns the exception that was raised if an error occurred while
 attempting to load the class. | 
addSuppressed, fillInStackTrace, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toStringpublic ClassNotFoundException()
ClassNotFoundException with no detail message.public ClassNotFoundException(String s)
ClassNotFoundException with the
 specified detail message.s - the detail message.public ClassNotFoundException(String s, Throwable ex)
ClassNotFoundException with the
 specified detail message and optional exception that was
 raised while loading the class.s - the detail messageex - the exception that was raised while loading the classpublic Throwable getException()
This method predates the general-purpose exception chaining facility.
 The Throwable.getCause() method is now the preferred means of
 obtaining this information.
Exception that was raised while loading a class Submit a bug or feature 
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