javax.crypto.spec

Class DESedeKeySpec

Implemented Interfaces:
KeySpec

public class DESedeKeySpec
extends Object
implements KeySpec

This class is a transparent wrapper for DES-EDE (Triple-DES) keys, which are arrays of 24 bytes.
Since:
1.4

Field Summary

static int
DES_EDE_KEY_LEN
The length of a triple-DES key, in bytes.

Constructor Summary

DESedeKeySpec(byte[] key)
Create a new DES-EDE key spec, copying the first 24 bytes from the byte array.
DESedeKeySpec(byte[] key, int offset)
Create a new DES-EDE key spec, starting at offset in the byte array.

Method Summary

byte[]
getKey()
Return the key as a byte array.
static boolean
isParityAdjusted(byte[] key, int offset)
Returns whether or not the given key is parity adjusted; i.e. every byte in the key has an odd number of "1" bits.

Methods inherited from class java.lang.Object

clone, equals, extends Object> getClass, finalize, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Details

DES_EDE_KEY_LEN

public static final int DES_EDE_KEY_LEN
The length of a triple-DES key, in bytes.
Field Value:
24

Constructor Details

DESedeKeySpec

public DESedeKeySpec(byte[] key)
            throws InvalidKeyException
Create a new DES-EDE key spec, copying the first 24 bytes from the byte array.
Parameters:
key - The key bytes.
Throws:
InvalidKeyException - If there are less than 24 bytes in the array.

DESedeKeySpec

public DESedeKeySpec(byte[] key,
                     int offset)
            throws InvalidKeyException
Create a new DES-EDE key spec, starting at offset in the byte array. The first 24 bytes starting at offset are copied.
Parameters:
key - The key bytes.
offset - The offset into the byte array at which to begin.
Throws:
InvalidKeyException - If there are less than 24 bytes starting at offset.

Method Details

getKey

public byte[] getKey()
Return the key as a byte array. This method does not copy the byte array.
Returns:
The key bytes.

isParityAdjusted

public static boolean isParityAdjusted(byte[] key,
                                       int offset)
            throws InvalidKeyException
Returns whether or not the given key is parity adjusted; i.e. every byte in the key has an odd number of "1" bits.
Parameters:
key - The key bytes, considered between [offset, offset+23]
offset - The offset into the byte array at which to begin.
Returns:
True if all bytes have an odd number of "1" bits.
Throws:
InvalidKeyException - If there are not enough bytes in the array.

DESedeKeySpec.java -- Keys for triple-DES. Copyright (C) 2004 Free Software Foundation, Inc. This file is part of GNU Classpath. GNU Classpath is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. GNU Classpath is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with GNU Classpath; see the file COPYING. If not, write to the Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA. Linking this library statically or dynamically with other modules is making a combined work based on this library. Thus, the terms and conditions of the GNU General Public License cover the whole combination. As a special exception, the copyright holders of this library give you permission to link this library with independent modules to produce an executable, regardless of the license terms of these independent modules, and to copy and distribute the resulting executable under terms of your choice, provided that you also meet, for each linked independent module, the terms and conditions of the license of that module. An independent module is a module which is not derived from or based on this library. If you modify this library, you may extend this exception to your version of the library, but you are not obligated to do so. If you do not wish to do so, delete this exception statement from your version.