public DESKeySpec(byte[] key) throws InvalidKeyException 
{
                                                                                       
        this(key, 0);
}

Creates a DESKeySpec object using the first 8 bytes in key as the key material for the DES key.

The bytes that constitute the DES key are those between key[0] and key[7] inclusive.

Parameters:

key - the buffer with the DES key material. The first 8 bytes of the buffer are copied to protect against subsequent modification.

Throws:

NullPointerException - if the given key material is null

InvalidKeyException - if the given key material is shorter than 8 bytes.

exception: NullPointerException - if the given key material is null

exception: InvalidKeyException - if the given key material is shorter than 8 bytes.

 public DESKeySpec(byte[] key,
    int offset) throws InvalidKeyException 
{
        if (key.length - offset <  DES_KEY_LEN) {
            throw new InvalidKeyException("Wrong key size");
        }
        this.key = new byte[DES_KEY_LEN];
        System.arraycopy(key, offset, this.key, 0, DES_KEY_LEN);
}

Creates a DESKeySpec object using the first 8 bytes in key, beginning at offset inclusive, as the key material for the DES key.

The bytes that constitute the DES key are those between key[offset] and key[offset+7] inclusive.

Parameters:

key - the buffer with the DES key material. The first 8 bytes of the buffer beginning at offset inclusive are copied to protect against subsequent modification.

offset - the offset in key, where the DES key material starts.

Throws:

NullPointerException - if the given key material is null

InvalidKeyException - if the given key material, starting at offset inclusive, is shorter than 8 bytes.

exception: NullPointerException - if the given key material is null

exception: InvalidKeyException - if the given key material, starting at offset inclusive, is shorter than 8 bytes.

 public byte[] getKey() 
{
        return (byte[])this.key.clone();
}

Returns the DES key material.

 public static boolean isParityAdjusted(byte[] key,
    int offset) throws InvalidKeyException 
{
            if (key == null) {
                throw new InvalidKeyException("null key");
            }
            if (key.length - offset <  DES_KEY_LEN) {
                throw new InvalidKeyException("Wrong key size");
            }
            for (int i = 0; i <  DES_KEY_LEN; i++) {
                int k = Integer.bitCount(key[offset++] & 0xff);
                if ((k & 1) == 0) {
                    return false;
                }
            }
            return true;
}

Checks if the given DES key material, starting at offset inclusive, is parity-adjusted.

 public static boolean isWeak(byte[] key,
    int offset) throws InvalidKeyException 
{
        if (key == null) {
            throw new InvalidKeyException("null key");
        }
        if (key.length - offset <  DES_KEY_LEN) {
            throw new InvalidKeyException("Wrong key size");
        }
        for (int i = 0; i <  WEAK_KEYS.length; i++) {
            boolean found = true;
            for (int j = 0; j <  DES_KEY_LEN && found == true; j++) {
                if (WEAK_KEYS[i][j] != key[j+offset]) {
                    found = false;
                }
            }
            if (found == true) {
                return found;
            }
        }
        return false;
}

Checks if the given DES key material is weak or semi-weak.