Java™ Platform
Standard Ed. 6
Class SecureRandomSpi

  extended by
All Implemented Interfaces:

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.

See Also:
SecureRandom, Serialized Form

Constructor Summary
Method Summary
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, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail


public SecureRandomSpi()
Method Detail


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.

seed - the seed.


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.

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


protected abstract byte[] engineGenerateSeed(int numBytes)
Returns the given number of seed bytes. This call may be used to seed other random number generators.

numBytes - the number of seed bytes to generate.
the seed bytes.

Java™ Platform
Standard Ed. 6

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