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

Since: API Level 1

public class

ExemptionMechanism

extends Object

java.lang.Object
↳	javax.crypto.ExemptionMechanism

Class Overview

This class implements the functionality of an exemption mechanism such as key recovery, key weakening, or key escrow.

Summary

Protected Constructors
	ExemptionMechanism(ExemptionMechanismSpi exmechSpi, Provider provider, String mechanism) Creates a `ExemptionMechanism` instance.

Public Methods
final int	genExemptionBlob(byte[] output) Generates the result key blob for this exemption mechanism and stores it into the `output` buffer.
final byte[]	genExemptionBlob() Generates the result key blob for this exemption mechanism.
final int	genExemptionBlob(byte[] output, int outputOffset) Generates the result key blob for this exemption mechanism and stores it into the `output` buffer at offset `outputOffset`.
final static ExemptionMechanism	getInstance(String algorithm, String provider) Returns a new `ExemptionMechansm` instance that provides the specified exemption mechanism algorithm from the specified provider.
final static ExemptionMechanism	getInstance(String algorithm, Provider provider) Returns a new `ExemptionMechanism` instance that provides the specified exemption mechanism algorithm from the specified provider.
final static ExemptionMechanism	getInstance(String algorithm) Returns a new `ExemptionMechanism` instance that provides the specified exemption mechanism algorithm.
final String	getName() Returns the name of this `ExemptionMechanism`.
final int	getOutputSize(int inputLen) Returns the size in bytes for the output buffer needed to hold the output of the next `genExemptionBlob()` call, given the specified `inputLen` (in bytes).
final Provider	getProvider() Returns the provider of this `ExemptionMechanism` instance.
final void	init(Key key, AlgorithmParameterSpec param) Initializes this `ExemptionMechanism` instance with the specified key and algorithm parameters.
final void	init(Key key) Initializes this `ExemptionMechanism` instance with the specified key.
final void	init(Key key, AlgorithmParameters param) Initializes this `ExemptionMechanism` instance with the specified key and algorithm parameters.
final boolean	isCryptoAllowed(Key key) Returns whether the result blob for this `ExemptionMechanism` instance has been generated successfully and that the specified key is the same as the one that was used to initialize and generate.

Protected Methods
void	finalize() Override to clear any key state in the instance.

[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 ExemptionMechanism (ExemptionMechanismSpi exmechSpi, Provider provider, String mechanism)

Since: API Level 1

Creates a ExemptionMechanism instance.

Parameters

exmechSpi	the implementation delegate.
provider	the associated provider.
mechanism	the name of the mechanism.

Public Methods

public final int genExemptionBlob (byte[] output)

Since: API Level 1

Generates the result key blob for this exemption mechanism and stores it into the output buffer.

Parameters

output	the output buffer for the result key blob.

Returns

the number of bytes written to the output buffer.

Throws

IllegalStateException	if this `ExemptionMechanism` instance is not initialized.
ShortBufferException	if the provided buffer is too small for the result key blob.
ExemptionMechanismException	if error(s) occur during generation.

public final byte[] genExemptionBlob ()

Since: API Level 1

Generates the result key blob for this exemption mechanism.

Returns

the result key blob for this exemption mechanism.

Throws

IllegalStateException	if this `ExemptionMechanism` instance is not initialized.
ExemptionMechanismException	if error(s) occur during generation.

public final int genExemptionBlob (byte[] output, int outputOffset)

Since: API Level 1

Generates the result key blob for this exemption mechanism and stores it into the output buffer at offset outputOffset.

Parameters

output	the output buffer for the result key blob.
outputOffset	the offset in the output buffer to start.

Returns

the number of bytes written to the output buffer.

Throws

IllegalStateException	if this `ExemptionMechanism` instance is not initialized.
ShortBufferException	if the provided buffer is too small for the result key blob.
ExemptionMechanismException	if error(s) occur during generation.

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

Since: API Level 1

Returns a new ExemptionMechansm instance that provides the specified exemption mechanism algorithm from the specified provider.

Parameters

algorithm	the name of the requested exemption mechanism.
provider	the name of the provider that is providing the algorithm.

Returns

the new ExemptionMechanism instance.

Throws

NoSuchAlgorithmException	if the specified algorithm is not provided by the specified provider.
NoSuchProviderException	if the specified provider is not available.
NullPointerException	if the algorithm parameter is `null`.
IllegalArgumentException	if the provider parameter is `null`.

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

Since: API Level 1

Returns a new ExemptionMechanism instance that provides the specified exemption mechanism algorithm from the specified provider.

Parameters

algorithm	the name of the requested exemption mechanism.
provider	the provider that is providing the algorithm.

Returns

the new ExemptionMechanism instance.

Throws

NoSuchAlgorithmException	if the specified algorithm is not provided by the specified provider.
NullPointerException	if the algorithm parameter is `null`.
IllegalArgumentException	if the provider parameter is `null`.

public static final ExemptionMechanism getInstance (String algorithm)

Since: API Level 1

Returns a new ExemptionMechanism instance that provides the specified exemption mechanism algorithm.

Parameters

algorithm	the name of the requested exemption mechanism.

Returns

the new ExemptionMechanism instance.

Throws

NoSuchAlgorithmException	if the specified algorithm is not available by any provider.
NullPointerException	if the algorithm parameter is `null`.

public final String getName ()

Since: API Level 1

Returns the name of this ExemptionMechanism.

Returns

the name of this ExemptionMechanism.

public final int getOutputSize (int inputLen)

Since: API Level 1

Returns the size in bytes for the output buffer needed to hold the output of the next genExemptionBlob() call, given the specified inputLen (in bytes).

Parameters

inputLen	the specified input length (in bytes).

Returns

the size in bytes for the output buffer.

Throws

IllegalStateException	if this `ExemptionMechanism` instance is not initialized.

public final Provider getProvider ()

Since: API Level 1

Returns the provider of this ExemptionMechanism instance.

Returns

the provider of this ExemptionMechanism instance.

public final void init (Key key, AlgorithmParameterSpec param)

Since: API Level 1

Initializes this ExemptionMechanism instance with the specified key and algorithm parameters.

Parameters

key	the key to initialize this instance with.
param	the parameters for this exemption mechanism algorithm.

Throws

InvalidKeyException	if the key cannot be used to initialize this mechanism.
InvalidAlgorithmParameterException	the the parameters cannot be used to initialize this mechanism.
ExemptionMechanismException	if error(s) occur during initialization.

public final void init (Key key)

Since: API Level 1

Initializes this ExemptionMechanism instance with the specified key.

Parameters

key	the key to initialize this instance with.

Throws

InvalidKeyException	if the key cannot be used to initialize this mechanism.
ExemptionMechanismException	if error(s) occur during initialization.

public final void init (Key key, AlgorithmParameters param)

Since: API Level 1

Initializes this ExemptionMechanism instance with the specified key and algorithm parameters.

Parameters

key	the key to initialize this instance with.
param	the parameters for this exemption mechanism algorithm.

Throws

InvalidKeyException	if the key cannot be used to initialize this mechanism.
InvalidAlgorithmParameterException	if the parameters cannot be used to initialize this mechanism.
ExemptionMechanismException	if error(s) occur during initialization.

public final boolean isCryptoAllowed (Key key)

Since: API Level 1

Returns whether the result blob for this ExemptionMechanism instance has been generated successfully and that the specified key is the same as the one that was used to initialize and generate.

Parameters

key	the key to verify.

Returns

whether the result blob for this ExemptionMechanism instance has been generated successfully.

Throws

ExemptionMechanismException	if an error occurs while determining whether the result blob has been generated successfully.

Protected Methods

protected void finalize ()

Since: API Level 1

Override to clear any key state in the instance.

Results

Interfaces

Classes

Exceptions

ExemptionMechanism

Class Overview

Summary

Protected Constructors

protected ExemptionMechanism (ExemptionMechanismSpi exmechSpi, Provider provider, String mechanism)

Parameters

Public Methods

public final int genExemptionBlob (byte[] output)

Parameters

Returns

Throws

public final byte[] genExemptionBlob ()

Returns

Throws

public final int genExemptionBlob (byte[] output, int outputOffset)

Parameters

Returns

Throws

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

Parameters

Returns

Throws

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

Parameters

Returns

Throws

public static final ExemptionMechanism getInstance (String algorithm)

Parameters

Returns

Throws

public final String getName ()

Returns

public final int getOutputSize (int inputLen)

Parameters

Returns

Throws

public final Provider getProvider ()

Returns

public final void init (Key key, AlgorithmParameterSpec param)

Parameters

Throws

public final void init (Key key)

Parameters

Throws

public final void init (Key key, AlgorithmParameters param)

Parameters

Throws

public final boolean isCryptoAllowed (Key key)

Parameters

Returns

Throws

Protected Methods

protected void finalize ()