Class RC5ParameterSpec

java.lang.Object

javax.crypto.spec.RC5ParameterSpec

All Implemented Interfaces:

AlgorithmParameterSpec

public class RC5ParameterSpec
extends Object
implements AlgorithmParameterSpec

This class specifies the parameters used with the RC5 algorithm.

The parameters consist of a version number, a rounds count, a word size, and optionally an initialization vector (IV) (only in feedback mode).

This class can be used to initialize a Cipher object that implements the RC5 algorithm.

Since:

1.4

External Specifications

• RFC 2040: The RC5, RC5-CBC, RC5-CBC-Pad, and RC5-CTS Algorithms

Constructor Summary

Constructors

Constructor	Description
RC5ParameterSpec(int version, int rounds, int wordSize)	Constructs a parameter set for RC5 from the given version, number of rounds and word size (in bits).
RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv)	Constructs a parameter set for RC5 from the given version, number of rounds, word size (in bits), and IV.
RC5ParameterSpec(int version, int rounds, int wordSize, byte[] iv, int offset)	Constructs a parameter set for RC5 from the given version, number of rounds, word size (in bits), and IV.

Method Summary

Modifier and Type	Method	Description
boolean	equals(Object obj)	Tests for equality between the specified object and this object.
byte[]	getIV()	Returns the IV or null if this parameter set does not contain an IV.
int	getRounds()	Returns the number of rounds.
int	getVersion()	Returns the version.
int	getWordSize()	Returns the word size in bits.
int	hashCode()	Calculates a hash code value for the object.

Methods declared in class Object

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

Modifier and Type	Method	Description
protected Object	clone()	Answers 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 void	finalize()	Deprecated, for removal: This API element is subject to removal in a future version. May cause performance issues, deadlocks and hangs.
final Class<? extends Object>	getClass()	Answers the unique instance of java.lang.Class which represents the class of the receiver.
final void	notify()	Causes one thread which is waiting on the receiver to be made ready to run.
final void	notifyAll()	Causes all threads which are waiting on the receiver to be made ready to run.
String	toString()	Answers a string containing a concise, human-readable description of the receiver.
final void	wait()	Causes the thread which sent this message to be made not ready to run pending some change in the receiver (as indicated by notify or notifyAll).
final void	wait(long time)	Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.
final void	wait(long time, int frac)	Causes the thread which sent this message to be made not ready to run either pending some change in the receiver (as indicated by notify or notifyAll) or the expiration of the timeout.

Constructor Details

RC5ParameterSpec

public RC5ParameterSpec(int version,
 int rounds,
 int wordSize)

Constructs a parameter set for RC5 from the given version, number of rounds and word size (in bits).

Parameters:

version - the version.

rounds - the number of rounds.

wordSize - the word size in bits.

RC5ParameterSpec

public RC5ParameterSpec(int version,
 int rounds,
 int wordSize,
 byte[] iv)

Constructs a parameter set for RC5 from the given version, number of rounds, word size (in bits), and IV.

Note that the size of the IV (block size) must be twice the word size. The bytes that constitute the IV are those between iv[0] and iv[2*(wordSize/8)-1] inclusive.

Parameters:

version - the version.

rounds - the number of rounds.

wordSize - the word size in bits.

iv - the buffer with the IV. The first 2*(wordSize/8) bytes of the buffer are copied to protect against subsequent modification.

Throws:

IllegalArgumentException - if iv is null or (iv.length < 2 * (wordSize / 8))

RC5ParameterSpec

public RC5ParameterSpec(int version,
 int rounds,
 int wordSize,
 byte[] iv,
 int offset)

Constructs a parameter set for RC5 from the given version, number of rounds, word size (in bits), and IV.

The IV is taken from iv, starting at offset inclusive. Note that the size of the IV (block size), starting at offset inclusive, must be twice the word size. The bytes that constitute the IV are those between iv[offset] and iv[offset+2*(wordSize/8)-1] inclusive.

Parameters:

version - the version.

rounds - the number of rounds.

wordSize - the word size in bits.

iv - the buffer with the IV. The first 2*(wordSize/8) bytes of the buffer beginning at offset inclusive are copied to protect against subsequent modification.

offset - the offset in iv where the IV starts.

Throws:

ArrayIndexOutOfBoundsException - if offset is negative.

IllegalArgumentException - if iv is null or (iv.length - offset < 2 * (wordSize / 8))

Method Details

getVersion

public int getVersion()

Returns the version.

Returns:

the version.

getRounds

public int getRounds()

Returns the number of rounds.

Returns:

the number of rounds.

getWordSize

public int getWordSize()

Returns the word size in bits.

Returns:

the word size in bits.

getIV

public byte[] getIV()

Returns the IV or null if this parameter set does not contain an IV.

Returns:

the IV or null if this parameter set does not contain an IV. Returns a new array each time this method is called.

equals

public boolean equals(Object obj)

Tests for equality between the specified object and this object. Two RC5ParameterSpec objects are considered equal if their version numbers, number of rounds, word sizes, and IVs are equal. (Two IV references are considered equal if both are null.)

Overrides:

equals in class Object

Parameters:

obj - the object to test for equality with this object.

Returns:

true if the objects are considered equal, false if obj is null or otherwise.

See Also:

• Object.hashCode()

hashCode

public int hashCode()

Calculates a hash code value for the object. Objects that are equal will also have the same hashcode.

Overrides:

hashCode in class Object

Returns:

the receiver's hash.

See Also:

• Object.equals(Object)