Added in API level 1

Summary: Ctors | Protected Ctors | Methods | Protected Methods | Inherited Methods

SecureRandomSpi

public abstract class SecureRandomSpi
extends Object implements Serializable

java.lang.Object
↳	java.security.SecureRandomSpi

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This class defines the Service Provider Interface (SPI) for the SecureRandom class.

All the abstract methods in this class must be implemented by each service provider who wishes to supply the implementation of a cryptographically strong pseudo-random number generator.

Summary

Public constructors
SecureRandomSpi() Constructor without a parameter.

Protected constructors
SecureRandomSpi(SecureRandomParameters params) Constructor with a parameter.

Public methods
String	toString() Returns a Human-readable string representation of this SecureRandom.

Protected methods
abstract byte[]	engineGenerateSeed(int numBytes) Returns the given number of seed bytes.
SecureRandomParameters	engineGetParameters() Returns the effective SecureRandomParameters for this SecureRandom instance.
void	engineNextBytes(byte[] bytes, SecureRandomParameters params) Generates a user-specified number of random bytes with additional parameters.
abstract void	engineNextBytes(byte[] bytes) Generates a user-specified number of random bytes.
void	engineReseed(SecureRandomParameters params) Reseeds this random object with entropy input read from its entropy source with additional parameters.
abstract void	engineSetSeed(byte[] seed) Reseeds this random object with the given seed.

Inherited methods

From class java.lang.Object Object clone() Creates and returns a copy of this object. boolean equals(Object obj) Indicates whether some other object is "equal to" this one. void finalize() Called by the garbage collector on an object when garbage collection determines that there are no more references to the object. final Class<?> getClass() Returns the runtime class of this Object. int hashCode() Returns a hash code value for the 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(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. 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() Causes the current thread to wait until it is awakened, typically by being notified or interrupted.

Public constructors

SecureRandomSpi

Added in API level 1

public SecureRandomSpi ()

Constructor without a parameter.

Protected constructors

SecureRandomSpi

Added in API level 35

protected SecureRandomSpi (SecureRandomParameters params)

Constructor with a parameter.

Parameters
params	SecureRandomParameters: the SecureRandomParameters object. This argument can be null.

Throws
IllegalArgumentException	if params is unrecognizable or unsupported by this SecureRandom

Public methods

toString

Added in API level 1

public String toString ()

Returns a Human-readable string representation of this SecureRandom.

Returns
String	the string representation

Protected methods

engineGenerateSeed

Added in API level 1

protected abstract byte[] engineGenerateSeed (int numBytes)

Returns the given number of seed bytes. This call may be used to seed other random number generators.

Parameters
numBytes	int: the number of seed bytes to generate.

Returns
byte[]	the seed bytes.

engineGetParameters

Added in API level 35

protected SecureRandomParameters engineGetParameters ()

Returns the effective SecureRandomParameters for this SecureRandom instance.

Implementation Requirements:

• The default implementation returns null.

Returns
SecureRandomParameters	the effective SecureRandomParameters parameters, or null if no parameters were used.

engineNextBytes

Added in API level 35

protected void engineNextBytes (byte[] bytes, 
                SecureRandomParameters params)

Generates a user-specified number of random bytes with additional parameters.

Some random number generators can only generate a limited amount of random bytes per invocation. If the size of bytes is greater than this limit, the implementation should invoke its generation process multiple times to completely fill the buffer before returning from this method.

Implementation Requirements:

• The default implementation throws an UnsupportedOperationException.

Parameters
bytes	byte: the array to be filled in with random bytes
params	SecureRandomParameters: additional parameters

Throws
UnsupportedOperationException	if the implementation has not overridden this method
IllegalArgumentException	if params is null, illegal or unsupported by this SecureRandom

engineNextBytes

Added in API level 1

protected abstract void engineNextBytes (byte[] bytes)

Generates a user-specified number of random bytes.

Some random number generators can only generate a limited amount of random bytes per invocation. If the size of bytes is greater than this limit, the implementation should invoke its generation process multiple times to completely fill the buffer before returning from this method.

Parameters
bytes	byte: the array to be filled in with random bytes.

engineReseed

Added in API level 35

protected void engineReseed (SecureRandomParameters params)

Reseeds this random object with entropy input read from its entropy source with additional parameters.

If this method is called by SecureRandom.reseed(), params will be null.

Do not override this method if the implementation does not support reseeding.

Implementation Requirements:

• The default implementation throws an UnsupportedOperationException.

Parameters
params	SecureRandomParameters: extra parameters, can be null.

Throws
UnsupportedOperationException	if the implementation has not overridden this method
IllegalArgumentException	if params is illegal or unsupported by this SecureRandom

engineSetSeed

Added in API level 1

protected abstract void engineSetSeed (byte[] seed)

Reseeds this random object with the given seed. The seed supplements, rather than replaces, the existing seed. Thus, repeated calls are guaranteed never to reduce randomness.

Parameters
seed	byte: the seed.