All Implemented Interfaces:

KeySpec

public class DESKeySpec
extends Object
implements KeySpec 

Since:

1.4

• Field Summary

  Fields

  Modifier and Type	Field	Description
  static int	DES_KEY_LEN	The constant which defines the length of a DES key in bytes.

• Constructor Summary

  Constructors

  Constructor	Description
  DESKeySpec (byte[] key)	Creates a DESKeySpec object using the first 8 bytes in key as the key material for the DES key.
  DESKeySpec (byte[] key, int offset)	Creates a DESKeySpec object using the first 8 bytes in key, beginning at offset inclusive, as the key material for the DES key.

• Method Summary

  All Methods

  Modifier and Type	Method	Description
  byte[]	getKey ()	Returns the DES key material.
  static boolean	isParityAdjusted (byte[] key, int offset)	Checks if the given DES key material, starting at offset inclusive, is parity-adjusted.
  static boolean	isWeak (byte[] key, int offset)	Checks if the given DES key material is weak or semi-weak.

  • Methods inherited from class java.lang.Object

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

• Field Detail

  • DES_KEY_LEN

    public static final int DES_KEY_LEN

    The constant which defines the length of a DES key in bytes.

    See Also:

    Constant Field Values

• Constructor Detail

  • DESKeySpec

    public DESKeySpec(byte[] key)
     throws InvalidKeyException 

    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.

  • DESKeySpec

    public DESKeySpec(byte[] key,
     int offset)
     throws InvalidKeyException 

    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.

• Method Detail

  • getKey

    public byte[] getKey()

    Returns the DES key material.

    Returns:

    the DES key material. Returns a new array each time this method is called.

  • isParityAdjusted

    public static boolean isParityAdjusted(byte[] key,
     int offset)
     throws InvalidKeyException 

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

    Parameters:

    key - the buffer with the DES key material.

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

    Returns:

    true if the given DES key material is parity-adjusted, false otherwise.

    Throws:

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

  • isWeak

    public static boolean isWeak(byte[] key,
     int offset)
     throws InvalidKeyException 

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

    Parameters:

    key - the buffer with the DES key material.

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

    Returns:

    true if the given DES key material is weak or semi-weak, false otherwise.

    Throws:

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