SecureRandomSpi
public
abstract
class
SecureRandomSpi
extends Object
implements
Serializable
java.lang.Object | |
↳ | java.security.SecureRandomSpi |
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 | |
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SecureRandomSpi(SecureRandomParameters params)
Constructor with a parameter. |
Public methods | |
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String
|
toString()
Returns a Human-readable string representation of this
|
Protected methods | |
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abstract
byte[]
|
engineGenerateSeed(int numBytes)
Returns the given number of seed bytes. |
SecureRandomParameters
|
engineGetParameters()
Returns the effective |
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 | |
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Public constructors
Protected constructors
SecureRandomSpi
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
public String toString ()
Returns a Human-readable string representation of this
SecureRandom
.
Returns | |
---|---|
String |
the string representation |
Protected methods
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 |
int : the number of seed bytes to generate. |
Returns | |
---|---|
byte[] |
the seed bytes. |
engineGetParameters
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
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
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
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
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. |