java.security

Class SecureRandomSpi

java.lang.Object

java.security.SecureRandomSpi

All Implemented Interfaces:

Serializable

Direct Known Subclasses:

NativeSecureRandomSpi

public abstract class SecureRandomSpi
extends Object
implements Serializable

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.

Since:

1.2

See Also:

SecureRandom, Serialized Form

Constructor Summary

Constructors

Constructor and Description
SecureRandomSpi()

Method Summary

Modifier and Type	Method and Description
protected abstract byte[]	engineGenerateSeed(int numBytes) Returns the given number of seed bytes.
protected abstract void	engineNextBytes(byte[] bytes) Generates a user-specified number of random bytes.
protected abstract void	engineSetSeed(byte[] seed) Reseeds this random object.

Methods inherited from class java.lang.Object

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

Constructor Detail

SecureRandomSpi

public SecureRandomSpi()

Method Detail

engineGenerateSeed

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 - the number of seed bytes to generate.

Returns:

the seed bytes.

engineNextBytes

protected abstract void engineNextBytes(byte[] bytes)

Generates a user-specified number of random bytes.

If a call to engineSetSeed had not occurred previously, the first call to this method forces this SecureRandom implementation to seed itself. This self-seeding will not occur if engineSetSeed was previously called.

Parameters:

bytes - the array to be filled in with random bytes.

engineSetSeed

protected abstract void engineSetSeed(byte[] seed)

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

Parameters:

seed - the seed.