Added in API level 1

Summary: Ctors | Methods | Protected Methods | Inherited Methods

MacSpi

public abstract class MacSpi
extends Object

java.lang.Object
↳	javax.crypto.MacSpi

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This class defines the Service Provider Interface (SPI) for the Mac class. All the abstract methods in this class must be implemented by each cryptographic service provider who wishes to supply the implementation of a particular MAC algorithm.

Implementations are free to implement the Cloneable interface.

Summary

Public constructors
MacSpi()

Public methods
Object	clone() Returns a clone if the implementation is cloneable.

Protected methods
abstract byte[]	engineDoFinal() Completes the MAC computation and resets the MAC for further use, maintaining the secret key that the MAC was initialized with.
abstract int	engineGetMacLength() Returns the length of the MAC in bytes.
abstract void	engineInit(Key key, AlgorithmParameterSpec params) Initializes the MAC with the given (secret) key and algorithm parameters.
abstract void	engineReset() Resets the MAC for further use, maintaining the secret key that the MAC was initialized with.
void	engineUpdate(ByteBuffer input) Processes input.remaining() bytes in the ByteBuffer input, starting at input.position().
abstract void	engineUpdate(byte input) Processes the given byte.
abstract void	engineUpdate(byte[] input, int offset, int len) Processes the first len bytes in input, starting at offset inclusive.

Inherited methods

From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the object. final void notify() Wakes up a single thread that is waiting on this object's monitor. final void notifyAll() Wakes up all threads that are waiting on this object's monitor. String toString() Returns a string representation of the object. final void wait(long timeoutMillis, int nanos) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait(long timeoutMillis) Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed. final void wait() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

MacSpi

Added in API level 1

public MacSpi ()

Public methods

clone

Added in API level 1

public Object clone ()

Returns a clone if the implementation is cloneable.

Returns
Object	a clone if the implementation is cloneable.

Throws
CloneNotSupportedException	if this is called on an implementation that does not support Cloneable.

Protected methods

engineDoFinal

Added in API level 1

protected abstract byte[] engineDoFinal ()

Completes the MAC computation and resets the MAC for further use, maintaining the secret key that the MAC was initialized with.

Returns
byte[]	the MAC result.

engineGetMacLength

Added in API level 1

protected abstract int engineGetMacLength ()

Returns the length of the MAC in bytes.

Returns
int	the MAC length in bytes.

engineInit

Added in API level 1

protected abstract void engineInit (Key key, 
                AlgorithmParameterSpec params)

Initializes the MAC with the given (secret) key and algorithm parameters.

Parameters
key	Key: the (secret) key.
params	AlgorithmParameterSpec: the algorithm parameters.

Throws
InvalidKeyException	if the given key is inappropriate for initializing this MAC.
InvalidAlgorithmParameterException	if the given algorithm parameters are inappropriate for this MAC.

engineReset

Added in API level 1

protected abstract void engineReset ()

Resets the MAC for further use, maintaining the secret key that the MAC was initialized with.

engineUpdate

Added in API level 1

protected void engineUpdate (ByteBuffer input)

Processes input.remaining() bytes in the ByteBuffer input, starting at input.position(). Upon return, the buffer's position will be equal to its limit; its limit will not have changed.

Subclasses should consider overriding this method if they can process ByteBuffers more efficiently than byte arrays.

Parameters
input	ByteBuffer: the ByteBuffer

engineUpdate

Added in API level 1

protected abstract void engineUpdate (byte input)

Processes the given byte.

Parameters
input	byte: the input byte to be processed.

engineUpdate

Added in API level 1

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

Processes the first len bytes in input, starting at offset inclusive.

Parameters
input	byte: the input buffer.
offset	int: the offset in input where the input starts.
len	int: the number of bytes to process.