javax.crypto

Class MacSpi

java.lang.Object

javax.crypto.MacSpi

Direct Known Subclasses:

BaseMac, OpenSSLMac

public abstract class MacSpi
extends Object

The Service-Provider Interface (SPI) definition for the Mac class.

See Also:

Mac

Constructor Summary

Constructors

Constructor and Description
MacSpi() Creates a new MacSpi instance.

Method Summary

Modifier and Type	Method and Description
Object	clone() Clones this MacSpi instance.
protected abstract byte[]	engineDoFinal() Computes the digest of this MAC based on the data previously specified in engineUpdate(byte) calls.
protected abstract int	engineGetMacLength() Returns the length of this MAC (in bytes).
protected abstract void	engineInit(Key key, AlgorithmParameterSpec params) Initializes this MacSpi instance with the specified key and algorithm parameters.
protected abstract void	engineReset() Resets this MacSpi instance to its initial state.
protected abstract void	engineUpdate(byte input) Updates this MacSpi instance with the specified byte.
protected abstract void	engineUpdate(byte[] input, int offset, int len) Updates this MacSpi instance with the data from the specified buffer input from the specified offset and length len.
protected void	engineUpdate(ByteBuffer input) Updates this MacSpi instance with the data from the specified buffer, starting at Buffer.position(), including the next Buffer.remaining() bytes.

Methods inherited from class java.lang.Object

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

Constructor Detail

MacSpi

public MacSpi()

Creates a new MacSpi instance.

Method Detail

engineGetMacLength

protected abstract int engineGetMacLength()

Returns the length of this MAC (in bytes).

Returns:

the length of this MAC (in bytes).

engineInit

protected abstract void engineInit(Key key,
                                   AlgorithmParameterSpec params)
                            throws InvalidKeyException,
                                   InvalidAlgorithmParameterException

Initializes this MacSpi instance with the specified key and algorithm parameters.

Parameters:

key - the key to initialize this algorithm.

params - the parameters for this algorithm.

Throws:

InvalidKeyException - if the specified key cannot be used to initialize this algorithm, or it is null.

InvalidAlgorithmParameterException - if the specified parameters cannot be used to initialize this algorithm.

engineUpdate

protected abstract void engineUpdate(byte input)

Updates this MacSpi instance with the specified byte.

Parameters:

input - the byte.

engineUpdate

protected abstract void engineUpdate(byte[] input,
                                     int offset,
                                     int len)

Updates this MacSpi instance with the data from the specified buffer input from the specified offset and length len.

Parameters:

input - the buffer.

offset - the offset in the buffer.

len - the length of the data in the buffer.

engineUpdate

protected void engineUpdate(ByteBuffer input)

Updates this MacSpi instance with the data from the specified buffer, starting at Buffer.position(), including the next Buffer.remaining() bytes.

Parameters:

input - the buffer.

engineDoFinal

protected abstract byte[] engineDoFinal()

Computes the digest of this MAC based on the data previously specified in engineUpdate(byte) calls.

This MacSpi instance is reverted to its initial state and can be used to start the next MAC computation with the same parameters or initialized with different parameters.

Returns:

the generated digest.

engineReset

protected abstract void engineReset()

Resets this MacSpi instance to its initial state.

This MacSpi instance is reverted to its initial state and can be used to start the next MAC computation with the same parameters or initialized with different parameters.

clone

public Object clone()
             throws CloneNotSupportedException

Clones this MacSpi instance.

Overrides:

clone in class Object

Returns:

the cloned instance.

Throws:

CloneNotSupportedException - if cloning is not supported.