Class PRNG

java.lang.Object
io.vertx.ext.auth.prng.PRNG
All Implemented Interfaces:
VertxContextPRNG
public class PRNG extends Object implements VertxContextPRNG
Wrapper around secure random that periodically seeds the PRNG with new entropy. To avoid entropy exhaustion the entropy is only refreshed if the PRNG is used. This introduces a new variable which reduces the probability of cracking the random number generator.
Author:
Paulo Lopes

  • Constructor Summary

    Constructors
    Constructor
    Description
    PRNG(Vertx vertx)
     

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    close()
    stop seeding the PRNG
    boolean
    nextBoolean()
    Returns a secure random boolean
    void
    nextBytes(byte[] bytes)
    Fills the given byte array with random bytes.
    double
    nextDouble()
    Returns a secure random double value.
    float
    nextFloat()
    Returns a secure random float value.
    double
    nextGaussian()
    Returns a secure random double value.
    int
    nextInt()
    Returns a secure random int
    int
    nextInt(int bound)
    Returns a secure random int, between 0 (inclusive) and the specified bound (exclusive).
    long
    nextLong()
    Returns a secure random long
    String
    nextString(int length)
    Returns a Base64 url encoded String of random data with the given length.

    Methods inherited from class Object

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

  • Constructor Details

    • PRNG

      public PRNG(Vertx vertx)

  • Method Details

    • close

      public void close()
      Description copied from interface: VertxContextPRNG
      stop seeding the PRNG
      Specified by:
      close in interface VertxContextPRNG

    • nextBytes

      public void nextBytes(byte[] bytes)
      Description copied from interface: VertxContextPRNG
      Fills the given byte array with random bytes.
      Specified by:
      nextBytes in interface VertxContextPRNG
      Parameters:
      bytes - a byte array.

    • nextInt

      public int nextInt()
      Description copied from interface: VertxContextPRNG
      Returns a secure random int
      Specified by:
      nextInt in interface VertxContextPRNG
      Returns:
      random int.

    • nextInt

      public int nextInt(int bound)
      Description copied from interface: VertxContextPRNG
      Returns a secure random int, between 0 (inclusive) and the specified bound (exclusive).
      Specified by:
      nextInt in interface VertxContextPRNG
      Parameters:
      bound - the upper bound (exclusive), which must be positive.
      Returns:
      random int.

    • nextBoolean

      public boolean nextBoolean()
      Description copied from interface: VertxContextPRNG
      Returns a secure random boolean
      Specified by:
      nextBoolean in interface VertxContextPRNG
      Returns:
      random boolean.

    • nextLong

      public long nextLong()
      Description copied from interface: VertxContextPRNG
      Returns a secure random long
      Specified by:
      nextLong in interface VertxContextPRNG
      Returns:
      random long.

    • nextFloat

      public float nextFloat()
      Description copied from interface: VertxContextPRNG
      Returns a secure random float value. The value is uniformly distributed between 0.0 and 1.0
      Specified by:
      nextFloat in interface VertxContextPRNG
      Returns:
      random float.

    • nextDouble

      public double nextDouble()
      Description copied from interface: VertxContextPRNG
      Returns a secure random double value. The value is uniformly distributed between 0.0 and 1.0
      Specified by:
      nextDouble in interface VertxContextPRNG
      Returns:
      random double.

    • nextGaussian

      public double nextGaussian()
      Description copied from interface: VertxContextPRNG
      Returns a secure random double value. The value is Gaussian ("normally") distributed with mean 0.0 and standard deviation 1.0
      Specified by:
      nextGaussian in interface VertxContextPRNG
      Returns:
      random double.

    • nextString

      public String nextString(int length)
      Description copied from interface: VertxContextPRNG
      Returns a Base64 url encoded String of random data with the given length. The length parameter refers to the length of the String before the encoding step.
      Specified by:
      nextString in interface VertxContextPRNG
      Parameters:
      length - the desired string length before Base64 encoding.
      Returns:
      A base 64 encoded string.