Class KDFSpi

java.lang.Object
javax.crypto.KDFSpi
public abstract class KDFSpi extends Object
This class defines the Service Provider Interface (SPI) for the Key Derivation Function (KDF) class.

All the abstract methods in this class must be implemented by each cryptographic service provider who wishes to supply the implementation of a particular key derivation function algorithm.

Implementations must provide a public constructor which accepts a KDFParameters object if they depend on the default implementation of Provider.Service.newInstance to construct KDFSpi instances. The constructor must call super(params) passing the parameters supplied. The constructor must also throw an InvalidAlgorithmParameterException if the supplied parameters are inappropriate. If a KDF object is instantiated with one of the getInstance methods that contains a KDFParameters parameter, the user-provided KDFParameters object will be passed to the constructor of the KDFSpi implementation. Otherwise, if it is instantiated with one of the getInstance methods without a KDFParameters parameter, a null value will be passed to the constructor.

Implementations which do not support KDFParameters must require null to be passed, otherwise an InvalidAlgorithmParameterException will be thrown. On the other hand, implementations which require KDFParameters should throw an InvalidAlgorithmParameterException upon receiving a null value if default parameters cannot be generated or upon receiving KDFParameters which are not supported by the implementation.

To aid the caller, implementations may return parameters with additional default values or supply random values as used by the underlying KDF algorithm. See engineGetParameters() for more details.

Since:
25
See Also:

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    KDFSpi(KDFParameters kdfParameters)
    The sole constructor.

  • Method Summary

    Modifier and Type
    Method
    Description
    protected abstract byte[]
    engineDeriveData(AlgorithmParameterSpec derivationSpec)
    Derives a key, returns raw data as a byte array.
    protected abstract SecretKey
    engineDeriveKey(String alg, AlgorithmParameterSpec derivationSpec)
    Derives a key, returned as a SecretKey object.
    protected abstract KDFParameters
    engineGetParameters()
    Returns the KDFParameters used with this KDF object.

    Methods declared in class Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
    Modifier and Type
    Method
    Description
    protected Object
    clone()
    Creates and returns a copy of this object.
    boolean
    equals(Object obj)
    Indicates whether some other object is "equal to" this one.
    protected void
    finalize()
    Deprecated, for removal: This API element is subject to removal in a future version.
    Finalization is deprecated and subject to removal in a future release.
    final Class<?>
    getClass()
    Returns the runtime class of this Object.
    int
    hashCode()
    Returns a hash code value for this object.
    final void
    notify()
    Wakes up a single thread that is waiting on this object's monitor.
    final void
    notifyAll()
    Wakes up all threads that are waiting on this object's monitor.
    String
    toString()
    Returns a string representation of the object.
    final void
    wait()
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted.
    final void
    wait(long timeoutMillis)
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.
    final void
    wait(long timeoutMillis, int nanos)
    Causes the current thread to wait until it is awakened, typically by being notified or interrupted, or until a certain amount of real time has elapsed.