java.lang
Class ClassNotFoundException

java.lang.Object
  |
  +--java.lang.Throwable
        |
        +--java.lang.Exception
              |
              +--java.lang.ClassNotFoundException
All Implemented Interfaces:
Serializable
public class ClassNotFoundException
extends Exception

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."

Since:
JDK1.0
See Also:
Class.forName(java.lang.String), ClassLoader.findSystemClass(java.lang.String), ClassLoader.loadClass(java.lang.String, boolean), Serialized Form

 

Constructor Summary

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.
 

 

Method Summary

 Throwable getCause()
    Returns the 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.
 
Methods inherited from class java.lang.Throwable
fillInStackTrace, getLocalizedMessage, getMessage, getStackTrace, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toString
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait
 

 

Constructor Detail

 

ClassNotFoundException

public ClassNotFoundException()
Constructs a ClassNotFoundException with no detail message.

 

ClassNotFoundException

public ClassNotFoundException(String s)
Constructs a ClassNotFoundException with the specified detail message.

Parameters:
s - the detail message.

 

ClassNotFoundException

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 - the detail message
ex - the exception that was raised while loading the class
Since:
1.2

 

Method Detail

 

getException

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:
the Exception that was raised while loading a class
Since:
1.2

 

getCause

public Throwable getCause()
Returns the the cause of this exception (the exception that was raised if an error occurred while attempting to load the class; otherwise null).

Overrides:
getCause in class Throwable
Returns:
the cause of this exception.
Since:
1.4