KeyAgreement - Android SDK

Summary: Protected Ctors | Methods | Inherited Methods | [Expand All]

Added in API level 1

public class

KeyAgreement

extends Object

java.lang.Object
↳	javax.crypto.KeyAgreement

Class Overview

This class provides the functionality for a key exchange protocol. This enables two or more parties to agree on a secret key for symmetric cryptography.

Summary

Protected Constructors
	KeyAgreement(KeyAgreementSpi keyAgreeSpi, Provider provider, String algorithm) Creates a new `KeyAgreement` instance.

Public Methods
final Key	doPhase(Key key, boolean lastPhase) Does the next (or the last) phase of the key agreement, using the specified key.
final SecretKey	generateSecret(String algorithm) Generates the shared secret.
final int	generateSecret(byte[] sharedSecret, int offset) Generates the shared secret and stores it into the buffer `sharedSecred` at `offset`.
final byte[]	generateSecret() Generates the shared secret.
final String	getAlgorithm() Returns the name of the key agreement algorithm.
final static KeyAgreement	getInstance(String algorithm, String provider) Creates a new `KeyAgreement` for the specified algorithm from the specified provider.
final static KeyAgreement	getInstance(String algorithm, Provider provider) Create a new `KeyAgreement` for the specified algorithm from the specified provider.
final static KeyAgreement	getInstance(String algorithm) Creates a new `KeyAgreement` for the specified algorithm.
final Provider	getProvider() Returns the provider for this `KeyAgreement` instance.
final void	init(Key key, SecureRandom random) Initializes this `KeyAgreement` with the specified key and the specified randomness source.
final void	init(Key key, AlgorithmParameterSpec params) Initializes this `KeyAgreement` with the specified key and the algorithm parameters.
final void	init(Key key, AlgorithmParameterSpec params, SecureRandom random) Initializes this `KeyAgreement` with the specified key, algorithm parameters and randomness source.
final void	init(Key key) Initializes this `KeyAgreement` with the specified key.

[Expand]

Inherited Methods

From class java.lang.Object

Object	clone() Creates and returns a copy of this `Object`.
boolean	equals(Object o) 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() Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object.
final void	wait(long millis, 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 millis) Causes the calling thread to wait until another thread calls the `notify()` or `notifyAll()` method of this object or until the specified timeout expires.

Protected Constructors

protected KeyAgreement (KeyAgreementSpi keyAgreeSpi, Provider provider, String algorithm)

Added in API level 1

Creates a new KeyAgreement instance.

Parameters

keyAgreeSpi	the SPI delegate.
provider	the provider providing this KeyAgreement.
algorithm	the name of the key agreement algorithm.

Public Methods

public final Key doPhase (Key key, boolean lastPhase)

Added in API level 1

Does the next (or the last) phase of the key agreement, using the specified key.

Parameters

key	the key received from the other party for this phase.
lastPhase	set to `true` if this is the last phase of this key agreement.

Returns

the intermediate key from this phase or null if there is no intermediate key for this phase.

Throws

InvalidKeyException	if the specified key cannot be used in this key agreement or this phase,
IllegalStateException	if this instance has not been initialized.

public final SecretKey generateSecret (String algorithm)

Added in API level 1

Generates the shared secret.

Parameters

algorithm	the algorithm to for the `SecretKey`

Returns

the shared secret as a SecretKey of the specified algorithm.

Throws

IllegalStateException	if this key agreement is not complete.
NoSuchAlgorithmException	if the specified algorithm for the secret key does not exists.
InvalidKeyException	if a `SecretKey` with the specified algorithm cannot be created using the generated shared secret.

public final int generateSecret (byte[] sharedSecret, int offset)

Added in API level 1

Generates the shared secret and stores it into the buffer sharedSecred at offset.

Parameters

sharedSecret	the buffer to store the shared secret.
offset	the offset in the buffer.

Returns

the number of bytes stored in the buffer.

Throws

IllegalStateException	if this key agreement is not complete.
ShortBufferException	if the specified buffer is too small for the shared secret.

public final byte[] generateSecret ()

Added in API level 1

Generates the shared secret.

Returns

the generated shared secret.

Throws

IllegalStateException	if this key agreement is not complete.

public final String getAlgorithm ()

Added in API level 1

Returns the name of the key agreement algorithm.

Returns

the name of the key agreement algorithm.

public static final KeyAgreement getInstance (String algorithm, String provider)

Added in API level 1

Creates a new KeyAgreement for the specified algorithm from the specified provider.

Parameters

algorithm	the name of the key agreement algorithm to create.
provider	the name of the provider that provides the requested algorithm.

Returns

a key agreement for the specified algorithm from the specified provider.

Throws

NoSuchAlgorithmException	if the specified provider cannot provide the requested algorithm.
NoSuchProviderException	if the specified provider does not exist.
IllegalArgumentException	if the specified provider name is `null` or empty.

public static final KeyAgreement getInstance (String algorithm, Provider provider)

Added in API level 1

Create a new KeyAgreement for the specified algorithm from the specified provider. The provider supplied does not have to be registered.

Parameters

algorithm	the name of the key agreement algorithm to create.
provider	the provider that provides the requested algorithm.

Returns

a key agreement for the specified algorithm from the specified provider.

Throws

NoSuchAlgorithmException	if the specified provider cannot provide the requested algorithm.
IllegalArgumentException	if the specified provider is `null`.
NullPointerException	if the specified algorithm name is `null`.

public static final KeyAgreement getInstance (String algorithm)

Added in API level 1

Creates a new KeyAgreement for the specified algorithm.

Parameters

algorithm	the name of the key agreement algorithm to create.

Returns

a key agreement for the specified algorithm.

Throws

NoSuchAlgorithmException	if no installed provider can provide the requested algorithm.
NullPointerException	if the specified algorithm is `null`.

public final Provider getProvider ()

Added in API level 1

Returns the provider for this KeyAgreement instance.

Returns

the provider for this KeyAgreement instance.

public final void init (Key key, SecureRandom random)

Added in API level 1

Initializes this KeyAgreement with the specified key and the specified randomness source.

Parameters

key	the key to initialize this key agreement.
random	the source for any randomness needed.

Throws

InvalidKeyException	if the specified key cannot be used to initialize this key agreement.

public final void init (Key key, AlgorithmParameterSpec params)

Added in API level 1

Initializes this KeyAgreement with the specified key and the algorithm parameters.

Parameters

key	the key to initialize this key agreement.
params	the parameters for this key agreement algorithm.

Throws

InvalidKeyException	if the specified key cannot be used to initialize this key agreement.
InvalidAlgorithmParameterException	if the specified parameters are invalid for this key agreement algorithm.

public final void init (Key key, AlgorithmParameterSpec params, SecureRandom random)

Added in API level 1

Initializes this KeyAgreement with the specified key, algorithm parameters and randomness source.

Parameters

key	the key to initialize this key agreement.
params	the parameters for this key agreement algorithm.
random	the source for any randomness needed.

Throws

InvalidKeyException	if the specified key cannot be used to initialize this key agreement.
InvalidAlgorithmParameterException	if the specified parameters are invalid for this key agreement algorithm.

public final void init (Key key)

Added in API level 1

Initializes this KeyAgreement with the specified key.

Parameters

key	the key to initialize this key agreement.

Throws

InvalidKeyException	if the specified key cannot be used to initialize this key agreement.

Results

Interfaces

Classes

Exceptions

KeyAgreement

Class Overview

Summary

Protected Constructors

protected KeyAgreement (KeyAgreementSpi keyAgreeSpi, Provider provider, String algorithm)

Parameters

Public Methods

public final Key doPhase (Key key, boolean lastPhase)

Parameters

Returns

Throws

public final SecretKey generateSecret (String algorithm)

Parameters

Returns

Throws

public final int generateSecret (byte[] sharedSecret, int offset)

Parameters

Returns

Throws

public final byte[] generateSecret ()

Returns

Throws

public final String getAlgorithm ()

Returns

public static final KeyAgreement getInstance (String algorithm, String provider)

Parameters

Returns

Throws

public static final KeyAgreement getInstance (String algorithm, Provider provider)

Parameters

Returns

Throws

public static final KeyAgreement getInstance (String algorithm)

Parameters

Returns

Throws

public final Provider getProvider ()

Returns

public final void init (Key key, SecureRandom random)

Parameters

Throws

public final void init (Key key, AlgorithmParameterSpec params)

Parameters

Throws

public final void init (Key key, AlgorithmParameterSpec params, SecureRandom random)

Parameters

Throws

public final void init (Key key)

Parameters

Throws