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added in API level 1

ClassNotFoundException

public class ClassNotFoundException
extends ReflectiveOperationException

java.lang.Object
   ↳ java.lang.Throwable
     ↳ java.lang.Exception
       ↳ java.lang.ReflectiveOperationException
         ↳ java.lang.ClassNotFoundException


Thrown when an application tries to load in a class through its string name using:

  • The forName method in class Class.
  • The findSystemClass method in class ClassLoader .
  • The 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."

Summary

Public constructors

ClassNotFoundException()

Constructs a ClassNotFoundException with no detail message.

ClassNotFoundException(String s)

Constructs a ClassNotFoundException with the specified detail message.

ClassNotFoundException(String s, Throwable ex)

Constructs a ClassNotFoundException with the specified detail message and optional exception that was raised while loading the class.

Public methods

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.

Inherited methods

Public constructors

ClassNotFoundException

added in API level 1
public ClassNotFoundException ()

Constructs a ClassNotFoundException with no detail message.

ClassNotFoundException

added in API level 1
public ClassNotFoundException (String s)

Constructs a ClassNotFoundException with the specified detail message.

Parameters
s String: the detail message.

ClassNotFoundException

added in API level 1
public ClassNotFoundException (String s, 
                Throwable ex)

Constructs a ClassNotFoundException with the specified detail message and optional exception that was raised while loading the class.

Parameters
s String: the detail message

ex Throwable: the exception that was raised while loading the class

Public methods

getCause

added in API level 1
public 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).

Returns
Throwable the cause of this exception.

getException

added in API level 1
public Throwable getException ()

Returns the exception that was raised if an error occurred while attempting to load the class. Otherwise, returns null.

This method predates the general-purpose exception chaining facility. The Throwable.getCause() method is now the preferred means of obtaining this information.

Returns
Throwable the Exception that was raised while loading a class