ClassNotFoundException (Java Platform SE 8 ) (original) (raw)

• java.lang.Object

• • java.lang.Throwable
  • • java.lang.Exception
      • • java.lang.ReflectiveOperationException
          * * java.lang.ClassNotFoundException

• All Implemented Interfaces:
  Serializable

public class ClassNotFoundException
extends ReflectiveOperationException
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 classClassLoader .

• 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

  Constructors

  Constructor	Description
  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

  All Methods Instance Methods Concrete Methods

  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; otherwisenull).
  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](../../java/lang/Throwable.html "class in java.lang")  
     `[addSuppressed](../../java/lang/Throwable.html#addSuppressed-java.lang.Throwable-), [fillInStackTrace](../../java/lang/Throwable.html#fillInStackTrace--), [getLocalizedMessage](../../java/lang/Throwable.html#getLocalizedMessage--), [getMessage](../../java/lang/Throwable.html#getMessage--), [getStackTrace](../../java/lang/Throwable.html#getStackTrace--), [getSuppressed](../../java/lang/Throwable.html#getSuppressed--), [initCause](../../java/lang/Throwable.html#initCause-java.lang.Throwable-), [printStackTrace](../../java/lang/Throwable.html#printStackTrace--), [printStackTrace](../../java/lang/Throwable.html#printStackTrace-java.io.PrintStream-), [printStackTrace](../../java/lang/Throwable.html#printStackTrace-java.io.PrintWriter-), [setStackTrace](../../java/lang/Throwable.html#setStackTrace-java.lang.StackTraceElement:A-), [toString](../../java/lang/Throwable.html#toString--)`  
     * ### Methods inherited from class java.lang.[Object](../../java/lang/Object.html "class in java.lang")  
     `[clone](../../java/lang/Object.html#clone--), [equals](../../java/lang/Object.html#equals-java.lang.Object-), [finalize](../../java/lang/Object.html#finalize--), [getClass](../../java/lang/Object.html#getClass--), [hashCode](../../java/lang/Object.html#hashCode--), [notify](../../java/lang/Object.html#notify--), [notifyAll](../../java/lang/Object.html#notifyAll--), [wait](../../java/lang/Object.html#wait--), [wait](../../java/lang/Object.html#wait-long-), [wait](../../java/lang/Object.html#wait-long-int-)`

• • Constructor Detail

     * #### ClassNotFoundException  
     public ClassNotFoundException()  
     Constructs a `ClassNotFoundException` with no detail message.  
     * #### ClassNotFoundException  
     public ClassNotFoundException([String](../../java/lang/String.html "class in java.lang") s)  
     Constructs a `ClassNotFoundException` with the specified detail message.  
     Parameters:  
     `s` \- the detail message.  
     * #### ClassNotFoundException  
     public ClassNotFoundException([String](../../java/lang/String.html "class in java.lang") s,  
                                   [Throwable](../../java/lang/Throwable.html "class in java.lang") 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](../../java/lang/Throwable.html "class in java.lang") 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()](../../java/lang/Throwable.html#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](../../java/lang/Throwable.html "class in java.lang") getCause()  
    Returns the cause of this exception (the exception that was raised if an error occurred while attempting to load the class; otherwise  
    null  
    ).  
    Overrides:  
    `[getCause](../../java/lang/Throwable.html#getCause--)` in class `[Throwable](../../java/lang/Throwable.html "class in java.lang")`  
    Returns:  
    the cause of this exception.  
    Since:  
    1.4

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