iaik.security.md

Class AbstractMessageDigest

java.lang.Object

java.security.MessageDigestSpi

java.security.MessageDigest

iaik.security.md.AbstractMessageDigest

All Implemented Interfaces:

java.lang.Cloneable

Direct Known Subclasses:

BLAKE224, BLAKE256, BLAKE384, BLAKE512, GOST3411, Md2, Md5, RipeMd128, RipeMd160, RipeMd256, RipeMd320, SHA, SHA32bit, SHA64bit, Whirlpool

public abstract class AbstractMessageDigest
extends java.security.MessageDigest
implements java.lang.Cloneable

This is the base class of most message digest implementations in this package.

Version:

File Revision 19

Method Summary

Modifier and Type	Method and Description
java.lang.Object	clone() Return a clone of this message digest that can be used independently of this instance.
protected byte[]	engineDigest() SPI: Completes the hash computation by performing final operations such as padding.
protected int	engineDigest(byte[] buf, int offset, int len) Calculates the digest value and writes it to the given output buffer.
int	engineGetDigestLength() SPI: Returns the length of the digest in bytes.
protected abstract void	engineReset() SPI: Resets this message digest for further use.
protected void	engineUpdate(byte input) SPI: Updates the data to be hashed with the specified byte.
protected void	engineUpdate(byte[] input, int offset, int len) SPI: Updates the data to be hashed with the specified number of bytes, beginning at the specified offset within the given byte array.

Methods inherited from class java.security.MessageDigest

digest, digest, digest, getAlgorithm, getDigestLength, getInstance, getInstance, getInstance, getProvider, isEqual, reset, toString, update, update, update, update

Methods inherited from class java.security.MessageDigestSpi

engineUpdate

Methods inherited from class java.lang.Object

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

Method Detail

clone

public java.lang.Object clone()

Return a clone of this message digest that can be used independently of this instance.

Overrides:

clone in class java.security.MessageDigest

Returns:

A clone of this message digest.

engineUpdate

protected final void engineUpdate(byte input)

SPI: Updates the data to be hashed with the specified byte.

Specified by:

engineUpdate in class java.security.MessageDigestSpi

Parameters:

input - the byte to be used for updating.

engineUpdate

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

SPI: Updates the data to be hashed with the specified number of bytes, beginning at the specified offset within the given byte array.

Specified by:

engineUpdate in class java.security.MessageDigestSpi

Parameters:

input - the byte array holding the data to be used for this update operation.

offset - the offset, indicating the start position within the given byte array.

len - the number of bytes to be obtained from the given byte array, starting at the given position.

engineDigest

protected byte[] engineDigest()

SPI: Completes the hash computation by performing final operations such as padding. Once engineDigest has been called, the engine should be reset. Resetting is the responsibility of the engine implementor.

Specified by:

engineDigest in class java.security.MessageDigestSpi

Returns:

The computed hash value.

See Also:

engineReset()

engineDigest

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

Calculates the digest value and writes it to the given output buffer.

Overrides:

engineDigest in class java.security.MessageDigestSpi

Parameters:

buf - the output buffer in which to write the digest

offset - the start offset in the output buffer

len - the length of the digest value.

Returns:

the length of the digest written to the output buffer.

Throws:

java.security.DigestException - if an error occurs when calculating the digest value.

engineGetDigestLength

public int engineGetDigestLength()

SPI: Returns the length of the digest in bytes.

May not be available for applications before JDK versions >= 1.2.x.

Overrides:

engineGetDigestLength in class java.security.MessageDigestSpi

Returns:

the length of the digest in bytes.

engineReset

protected abstract void engineReset()

SPI: Resets this message digest for further use.

Specified by:

engineReset in class java.security.MessageDigestSpi