OpenJDK 27 · java.lang.ClassNotFoundException · APIdia, the JavaDoc alternative

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.

Field Summary

Modifier and Type	Field and Description
private static final ObjectStreamField[]	serialPersistentFields Serializable fields for ClassNotFoundException.
private static final long	serialVersionUID Hides java.lang.ReflectiveOperationException.serialVersionUID. use serialVersionUID from JDK 1.1.X for interoperability

Constructor Summary

Access	Constructor and Description
public	ClassNotFoundException() Constructs a `ClassNotFoundException` with no detail message.
public	ClassNotFoundException(String the detail message. s) Constructs a `ClassNotFoundException` with the specified detail message.
public	ClassNotFoundException(String the detail message s, Throwable the exception that was raised while loading the class 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 and Description
public Throwable	Returns: the `Exception` that was raised while loading a class getException() Returns the exception that was raised if an error occurred while attempting to load the class.
private void	readObject(ObjectInputStream the `ObjectInputStream` from which data is read s) Hides java.lang.Throwable.readObject. Reconstitutes the ClassNotFoundException instance from a stream and initialize the cause properly when deserializing from an older version.
private void	writeObject(ObjectOutputStream the `ObjectOutputStream` to which data is written out) Hides java.lang.Throwable.writeObject. To maintain compatibility with older implementation, write a serial "ex" field with the cause as the value.

Field Detail

serialPersistentFields	back to summary
private static final ObjectStreamField[] serialPersistentFields Serializable fields for ClassNotFoundException. Annotations @Serial Serial Fields: ex:`Throwable` the `Throwable`

serialVersionUID	back to summary
private static final long serialVersionUID Hides java.lang.ReflectiveOperationException.serialVersionUID. use serialVersionUID from JDK 1.1.X for interoperability Annotations @Serial

serialVersionUID

back to summary

private static final long serialVersionUID

Hides java.lang.ReflectiveOperationException.serialVersionUID.

use serialVersionUID from JDK 1.1.X for interoperability

Annotations

@Serial

Constructor Detail

ClassNotFoundException	back to summary
public ClassNotFoundException() Constructs a `ClassNotFoundException` with no detail message.

ClassNotFoundException back to summary

ClassNotFoundException	back to summary
public ClassNotFoundException(String s) Constructs a `ClassNotFoundException` with the specified detail message. Parameters s:String the detail message.

public ClassNotFoundException(String s)

Constructs a ClassNotFoundException with the specified detail message.

Parameters

s:String: the detail message.

ClassNotFoundException back to summary

ClassNotFoundException	back to summary
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 Since 1.2

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

Since

1.2

Method Detail

getException back to summary

getException	back to summary
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:Throwable the `Exception` that was raised while loading a class Since 1.2

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

readObject back to summary

readObject	back to summary
private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException Hides java.lang.Throwable.readObject. Reconstitutes the ClassNotFoundException instance from a stream and initialize the cause properly when deserializing from an older version. The getException and getCause method returns the private "ex" field in the older implementation and ClassNotFoundException::cause was set to null. Parameters s:ObjectInputStream the `ObjectInputStream` from which data is read Annotations @Serial Exceptions IOException: if an I/O error occurs ClassNotFoundException: if a serialized class cannot be loaded

private void readObject(ObjectInputStream s) throws IOException, ClassNotFoundException

Hides java.lang.Throwable.readObject.

Reconstitutes the ClassNotFoundException instance from a stream and initialize the cause properly when deserializing from an older version. The getException and getCause method returns the private "ex" field in the older implementation and ClassNotFoundException::cause was set to null.

Parameters

s:ObjectInputStream: the ObjectInputStream from which data is read

Annotations

@Serial

Exceptions

IOException:: if an I/O error occurs
ClassNotFoundException:: if a serialized class cannot be loaded

writeObject back to summary

writeObject	back to summary
private void writeObject(ObjectOutputStream out) throws IOException Hides java.lang.Throwable.writeObject. To maintain compatibility with older implementation, write a serial "ex" field with the cause as the value. Parameters out:ObjectOutputStream the `ObjectOutputStream` to which data is written Annotations @Serial Exceptions IOException: if an I/O error occurs

private void writeObject(ObjectOutputStream out) throws IOException

Hides java.lang.Throwable.writeObject.

To maintain compatibility with older implementation, write a serial "ex" field with the cause as the value.

Parameters

out:ObjectOutputStream: the ObjectOutputStream to which data is written

Annotations

@Serial

Exceptions

IOException:: if an I/O error occurs

public Class ClassNotFoundException

Field Summary

Constructor Summary

Method Summary

Field Detail

Constructor Detail

Method Detail