IvParameterSpec

AI-generated Key Takeaways

• IvParameterSpec specifies an initialization vector (IV) used by ciphers in feedback mode, such as DES in CBC mode and RSA with OAEP encoding.

• It provides constructors to create an IvParameterSpec object from a byte array, specifying either the entire array or a specific range within the array as the IV.

• The getIV() method returns a copy of the initialization vector.

• IvParameterSpec is an implementation of AlgorithmParameterSpec.

public class IvParameterSpec extends Object
implements AlgorithmParameterSpec

This class specifies an initialization vector (IV). Examples which use IVs are ciphers in feedback mode, e.g., DES in CBC mode and RSA ciphers with OAEP encoding operation.

Public Constructor Summary

	IvParameterSpec(byte[] iv) Creates an IvParameterSpec object using the bytes in iv as the IV.
	IvParameterSpec(byte[] iv, int offset, int len) Creates an IvParameterSpec object using the first len bytes in iv, beginning at offset inclusive, as the IV.

Public Method Summary

byte[]

getIV() Returns the initialization vector (IV).

Inherited Method Summary

From class java.lang.Object

Object	clone() Creates and returns a copy of this Object.
boolean	equals(Object obj) Compares this instance with the specified object and indicates if they are equal.
void	finalize() Invoked when the garbage collector has detected that this instance is no longer reachable.
final Class<?>	getClass() Returns the unique instance of Class that represents this object's class.
int	hashCode() Returns an integer hash code for this object.
final void	notify() Causes a thread which is waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
final void	notifyAll() Causes all threads which are waiting on this object's monitor (by means of calling one of the wait() methods) to be woken up.
String	toString() Returns a string containing a concise, human-readable description of this object.
final void	wait(long timeout, int nanos) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait(long timeout) Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object or until the specified timeout expires.
final void	wait() Causes the calling thread to wait until another thread calls the notify() or notifyAll() method of this object.

Public Constructors

public IvParameterSpec (byte[] iv)

Creates an IvParameterSpec object using the bytes in iv as the IV.

Parameters

iv	the buffer with the IV. The contents of the buffer are copied to protect against subsequent modification.

Throws

NullPointerException	if iv is null

public IvParameterSpec (byte[] iv, int offset, int len)

Creates an IvParameterSpec object using the first len bytes in iv, beginning at offset inclusive, as the IV.

The bytes that constitute the IV are those between iv[offset] and iv[offset+len-1] inclusive.

Parameters

iv	the buffer with the IV. The first len bytes of the buffer beginning at offset inclusive are copied to protect against subsequent modification.
offset	the offset in iv where the IV starts.
len	the number of IV bytes.

Throws

IllegalArgumentException	if iv is null or (iv.length - offset < len)
ArrayIndexOutOfBoundsException	is thrown if offset or len index bytes outside the iv.

Public Methods

public byte[] getIV ()

Returns the initialization vector (IV).

Returns

• the initialization vector (IV). Returns a new array each time this method is called.