Class ClassNotFoundException

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 class ClassLoader .
The loadClass method in class ClassLoader.

but no definition for the class with the specified name could be found.

Since:

1.0

See Also:

Constructor Summary

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

Modifier and Type	Method	Description
`Throwable`	`getException()`	Returns the exception that was raised if an error occurred while attempting to load the class.

Methods declared in class Throwable

addSuppressed, fillInStackTrace, getCause, getLocalizedMessage, getMessage, getStackTrace, getSuppressed, initCause, printStackTrace, printStackTrace, printStackTrace, setStackTrace, toString

Methods declared in class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Constructor Details

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 Details

getException

public Throwable getException()

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

API Note:: 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

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https://docs.oracle.com/en/java/javase/25/docs/api/java.base/java/lang/ClassNotFoundException.html