RandomSource (I2P Anonymous Network - Java Documentation

java.lang.Object
- java.util.Random
- - java.security.SecureRandom
  - - net.i2p.util.RandomSource

All Implemented Interfaces:

Serializable, EntropyHarvester

Direct Known Subclasses:

FortunaRandomSource
```
public class RandomSource
extends SecureRandom
implements EntropyHarvester
```
Singleton for whatever PRNG i2p uses.

Author:

jrandom

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type Field Description

protected I2PAppContext _context

Fields
Modifier and Type	Field	Description
`protected I2PAppContext`	`_context`

Constructor Summary

Constructors
Constructor Description

RandomSource(I2PAppContext context)
Deprecated - do not instantiate this directly, as you won't get the good one (Fortuna).

Constructors
Constructor	Description
`RandomSource(I2PAppContext context)`	Deprecated - do not instantiate this directly, as you won't get the good one (Fortuna).

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`feedEntropy(String source, byte[] data, int offset, int len)`	Feed the entropy pools with data[offset:offset+len]
`void`	`feedEntropy(String source, long data, int bitoffset, int bits)`	Feed the entropy pools with the bits in the data
`static RandomSource`	`getInstance()`	Singleton for whatever PRNG i2p uses.
`EntropyHarvester`	`harvester()`
`boolean`	`initSeed(byte[] buf)`	May block up to 10 seconds
`void`	`loadSeed()`	May block up to 10 seconds
`void`	`nextBytes(byte[] buf, int offset, int length)`	Not part of java.util.SecureRandom, but added since Fortuna supports it.
`int`	`nextInt(int n)`	According to the java docs (http://java.sun.com/j2se/1.4.1/docs/api/java/util/Random.html#nextInt(int)) nextInt(n) should return a number between 0 and n (including 0 and excluding n).
`long`	`nextLong(long n)`	Like the modified nextInt, nextLong(n) returns a random number from 0 through n, including 0, excluding n.
`void`	`saveSeed()`
`static void`	`writeSeed(byte[] buf)`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from class java.util.Random
doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, nextBoolean, nextDouble, nextFloat, nextGaussian, nextInt, nextLong

Methods inherited from class java.security.SecureRandom
generateSeed, getAlgorithm, getInstance, getInstance, getInstance, getInstance, getInstance, getInstance, getInstanceStrong, getParameters, getProvider, getSeed, next, nextBytes, nextBytes, reseed, reseed, setSeed, setSeed, toString

- Field Detail
  - _context
```
protected final transient I2PAppContext _context
```
- Constructor Detail
  - RandomSource
```
public RandomSource(I2PAppContext context)
```
    Deprecated - do not instantiate this directly, as you won't get the good one (Fortuna). Use getInstance() or I2PAppContext.getGlobalContext().random() to get the FortunaRandomSource instance.
- Method Detail
  - getInstance
```
public static RandomSource getInstance()
```
    Singleton for whatever PRNG i2p uses. Same as I2PAppContext.getGlobalContext().random(); use context.random() if you have a context already.
    
    Returns:
    
    I2PAppContext.getGlobalContext().random()
  - nextInt
```
public int nextInt(int n)
```
    According to the java docs (http://java.sun.com/j2se/1.4.1/docs/api/java/util/Random.html#nextInt(int)) nextInt(n) should return a number between 0 and n (including 0 and excluding n). However, their pseudocode, as well as sun's, kaffe's, and classpath's implementation INCLUDES NEGATIVE VALUES. Ok, so we're going to have it return between 0 and n (including 0, excluding n), since thats what it has been used for. This code unused, see FortunaRandomSource override
    
    Overrides:
    
    nextInt in class Random
  - nextLong
```
public long nextLong(long n)
```
    Like the modified nextInt, nextLong(n) returns a random number from 0 through n, including 0, excluding n. This code unused, see FortunaRandomSource override
  - nextBytes
```
public void nextBytes(byte[] buf,
                      int offset,
                      int length)
```
    Not part of java.util.SecureRandom, but added since Fortuna supports it. This code unused, see FortunaRandomSource override
    
    Since:
    
    0.8.12
  - harvester
```
public EntropyHarvester harvester()
```
  - feedEntropy
```
public void feedEntropy(String source,
                        long data,
                        int bitoffset,
                        int bits)
```
    Description copied from interface: EntropyHarvester
    
    Feed the entropy pools with the bits in the data
    
    Specified by:
    
    feedEntropy in interface EntropyHarvester
    
    Parameters:
    
    source - origin of the entropy, allowing the harvester to determine how much to value the data
    
    bitoffset - bit index into the data array to start (using java standard big-endian)
    
    bits - how many bits to use
  - feedEntropy
```
public void feedEntropy(String source,
                        byte[] data,
                        int offset,
                        int len)
```
    Description copied from interface: EntropyHarvester
    
    Feed the entropy pools with data[offset:offset+len]
    
    Specified by:
    
    feedEntropy in interface EntropyHarvester
    
    Parameters:
    
    source - origin of the entropy, allowing the harvester to determine how much to value the data
    
    offset - index into the data array to start
    
    len - how many bytes to use
  - loadSeed
```
public void loadSeed()
```
    May block up to 10 seconds
  - saveSeed
```
public void saveSeed()
```
  - writeSeed
```
public static final void writeSeed(byte[] buf)
```
  - initSeed
```
public final boolean initSeed(byte[] buf)
```
    May block up to 10 seconds

Class RandomSource

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from class java.util.Random

Methods inherited from class java.security.SecureRandom

Field Detail

_context

Constructor Detail

RandomSource

Method Detail

getInstance

nextInt

nextLong

nextBytes

harvester

feedEntropy

feedEntropy

loadSeed

saveSeed

writeSeed

initSeed