java.security
Class MessageDigestSpi

java.lang.Object
  java.security.MessageDigestSpi

Direct Known Subclasses:

MessageDigest

public abstract class MessageDigestSpi
extends Object

This class is a Service Provider Interface (therefore the Spi suffix) for digest algorithms to be supplied by providers. Examples of digest algorithms are MD5 and SHA. A digest is a secure hash function for a stream of bytes, like a fingerprint for the stream of bytes.

Constructor Summary

MessageDigestSpi()

Method Summary

Object	clone() Returns a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.
protected abstract byte[]	engineDigest()
protected int	engineDigest(byte[] buf, int offset, int len)
protected int	engineGetDigestLength()
protected abstract void	engineReset()
protected abstract void	engineUpdate(byte input)
protected abstract void	engineUpdate(byte[] input, int offset, int len)
protected void	engineUpdate(ByteBuffer input)

Methods inherited from class java.lang.Object

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

Constructor Detail

MessageDigestSpi

public MessageDigestSpi()

Method Detail

engineGetDigestLength

protected int engineGetDigestLength()

engineUpdate

protected abstract void engineUpdate(byte input)

engineUpdate

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

engineUpdate

protected void engineUpdate(ByteBuffer input)

engineDigest

protected abstract byte[] engineDigest()

engineDigest

protected int engineDigest(byte[] buf,
                           int offset,
                           int len)
                    throws DigestException

Throws:

DigestException

engineReset

protected abstract void engineReset()

clone

public Object clone()
             throws CloneNotSupportedException

Description copied from class: Object

Returns a new instance of the same class as the receiver, whose slots have been filled in with the values in the slots of the receiver.

Classes which wish to support cloning must specify that they implement the Cloneable interface, since the implementation checks for this.

Overrides:

clone in class Object

Returns:

Object a shallow copy of this object.

Throws:

CloneNotSupportedException - if the receiver's class does not implement the interface Cloneable.