Package org.opensaml.xmlsec.derivation

Class KeyDerivationSupport

java.lang.Object

org.opensaml.xmlsec.derivation.KeyDerivationSupport

public final class KeyDerivationSupport
extends Object

Support key derivation operations.

Constructor Summary

Constructors

Modifier	Constructor	Description
private	KeyDerivationSupport()	Constructor.

Method Summary

Modifier and Type	Method	Description
static int	getEffectiveKeyLength(String algorithmURI, Integer specifiedKeyLength)	Get the effective key length based on the specified algorithm URI and the specified key length, if present.
static String	getJCAKeyAlgorithm(String algorithmURI)	Get the JCA key algorithm which corresponds to the specified algorithm URI.

Methods inherited from class java.lang.Object

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

Constructor Details

KeyDerivationSupport

private KeyDerivationSupport()

Constructor.

Method Details

getJCAKeyAlgorithm

@Nonnull
public static String getJCAKeyAlgorithm(@Nonnull
 String algorithmURI)
                                 throws KeyDerivationException

Get the JCA key algorithm which corresponds to the specified algorithm URI.

Parameters:

algorithmURI - the algorithm URI with which the derived key will be user

Returns:

the JCA key algorithm

Throws:

KeyDerivationException - if key algorithm could not be determined

getEffectiveKeyLength

public static int getEffectiveKeyLength(@Nonnull
 String algorithmURI,
 @Nullable
 Integer specifiedKeyLength)
                                 throws KeyDerivationException

Get the effective key length based on the specified algorithm URI and the specified key length, if present.

If the algorithm URI implies a key length and the specified key length is non-null, the lengths must match or an exception will be thrown. If the algorithm URI does not imply a key length and the specified length is null, and exception will be thrown.

Parameters:

algorithmURI - the algorithm URI with which the derived key will be used

specifiedKeyLength - an explicitly specified key length

Returns:

the effective key length

Throws:

KeyDerivationException - if algorithm and specified key lengths are not consistent