DHParameterSpec

public class DHParameterSpec extends Object
implements AlgorithmParameterSpec

This class specifies the set of parameters used with the Diffie-Hellman algorithm, as specified in PKCS #3: Diffie-Hellman Key-Agreement Standard.

A central authority generates parameters and gives them to the two entities seeking to generate a secret key. The parameters are a prime p, a base g, and optionally the length in bits of the private value, l.

It is possible that more than one instance of parameters may be generated by a given central authority, and that there may be more than one central authority. Indeed, each individual may be its own central authority, with different entities having different parameters.

Note that this class does not perform any validation on specified parameters. Thus, the specified values are returned directly even if they are null.

See Also

• KeyAgreement

Public Constructor Summary

	DHParameterSpec(BigInteger p, BigInteger g) Constructs a parameter set for Diffie-Hellman, using a prime modulus p and a base generator g.
	DHParameterSpec(BigInteger p, BigInteger g, int l) Constructs a parameter set for Diffie-Hellman, using a prime modulus p, a base generator g, and the size in bits, l, of the random exponent (private value).

Public Method Summary

BigInteger	getG() Returns the base generator g.
int	getL() Returns the size in bits, l, of the random exponent (private value).
BigInteger	getP() Returns the prime modulus p.

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 DHParameterSpec (BigInteger p, BigInteger g)

Constructs a parameter set for Diffie-Hellman, using a prime modulus p and a base generator g.

Parameters

p	the prime modulus
g	the base generator

public DHParameterSpec (BigInteger p, BigInteger g, int l)

Constructs a parameter set for Diffie-Hellman, using a prime modulus p, a base generator g, and the size in bits, l, of the random exponent (private value).

Parameters

p	the prime modulus
g	the base generator
l	the size in bits of the random exponent (private value)

Public Methods

public BigInteger getG ()

Returns the base generator g.

Returns

• the base generator g

public int getL ()

Returns the size in bits, l, of the random exponent (private value).

Returns

• the size in bits, l, of the random exponent (private value), or 0 if this size has not been set

public BigInteger getP ()

Returns the prime modulus p.

Returns

• the prime modulus p