javax.crypto

Class MacSpi


  • public abstract class MacSpi
extends Object
    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.

    Since:
    1.4

    • Constructor Summary

      Constructors

      Constructor and Description
      MacSpi()
       

    • Method Summary

      Modifier and Type Method and Description
      Object clone()
      Returns a clone if the implementation is cloneable.
      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.
      protected abstract int engineGetMacLength()
      Returns the length of the MAC in bytes.
      protected abstract void engineInit(Key key, AlgorithmParameterSpec params)
      Initializes the MAC with the given (secret) key and algorithm parameters.
      protected abstract void engineReset()
      Resets the MAC for further use, maintaining the secret key that the MAC was initialized with.
      protected abstract void engineUpdate(byte input)
      Processes the given byte.
      protected abstract void engineUpdate(byte[] input, int offset, int len)
      Processes the first len bytes in input, starting at offset inclusive.
      protected void engineUpdate(ByteBuffer input)
      Processes input.remaining() bytes in the ByteBuffer input, starting at input.position().

    • Constructor Detail

      • MacSpi

        public MacSpi()

    • Method Detail

      • engineGetMacLength

        protected abstract int engineGetMacLength()
        Returns the length of the MAC in bytes.
        Returns:
        the MAC length in bytes.

      • engineUpdate

        protected abstract void engineUpdate(byte input)
        Processes the given byte.
        Parameters:
        input - the input byte to be processed.

      • engineUpdate

        protected abstract void engineUpdate(byte[] input,
                                     int offset,
                                     int len)
        Processes the first len bytes in input, starting at offset inclusive.
        Parameters:
        input - the input buffer.
        offset - the offset in input where the input starts.
        len - the number of bytes to process.

      • engineUpdate

        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 - the ByteBuffer
        Since:
        1.5

      • engineDoFinal

        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:
        the MAC result.

      • engineReset

        protected abstract void engineReset()
        Resets the MAC for further use, maintaining the secret key that the MAC was initialized with.