Class ThreadLocalRandom

java.lang.Object
java.util.Random
io.netty.util.internal.ThreadLocalRandom
All Implemented Interfaces:
java.io.Serializable
@Deprecated public final class ThreadLocalRandom extends java.util.Random
Deprecated.
A random number generator isolated to the current thread. Like the global Random generator used by the Math class, a ThreadLocalRandom is initialized with an internally generated seed that may not otherwise be modified. When applicable, use of ThreadLocalRandom rather than shared Random objects in concurrent programs will typically encounter much less overhead and contention. Use of ThreadLocalRandom is particularly appropriate when multiple tasks (for example, each a
invalid reference 
io.netty.util.internal.chmv8.ForkJoinTask
) use random numbers in parallel in thread pools.

Usages of this class should typically be of the form: ThreadLocalRandom.current().nextX(...) (where X is Int, Long, etc). When all usages are of this form, it is never possible to accidentally share a ThreadLocalRandom across multiple threads.

This class also provides additional commonly used bounded random generation methods. //since 1.7 //author Doug Lea

See Also:

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    private static final long
    addend
    Deprecated.
     
    (package private) boolean
    initialized
    Deprecated.
    Initialization flag to permit calls to setSeed to succeed only while executing the Random constructor.
    private static long
    initialSeedUniquifier
    Deprecated.
     
    private static final InternalLogger
    logger
    Deprecated.
     
    private static final long
    mask
    Deprecated.
     
    private static final long
    multiplier
    Deprecated.
     
    private long
    pad0
    Deprecated.
     
    private long
    pad1
    Deprecated.
     
    private long
    pad2
    Deprecated.
     
    private long
    pad3
    Deprecated.
     
    private long
    pad4
    Deprecated.
     
    private long
    pad5
    Deprecated.
     
    private long
    pad6
    Deprecated.
     
    private long
    pad7
    Deprecated.
     
    private long
    rnd
    Deprecated.
    The random seed.
    private static long
    seedGeneratorEndTime
    Deprecated.
     
    private static final long
    seedGeneratorStartTime
    Deprecated.
     
    private static final java.lang.Thread
    seedGeneratorThread
    Deprecated.
     
    private static final java.util.concurrent.BlockingQueue<java.lang.Long>
    seedQueue
    Deprecated.
     
    private static final java.util.concurrent.atomic.AtomicLong
    seedUniquifier
    Deprecated.
     
    private static final long
    serialVersionUID
    Deprecated.
     

  • Constructor Summary

    Constructors
    Constructor
    Description
    ThreadLocalRandom()
    Deprecated.
    Constructor called only by localRandom.initialValue.

  • Method Summary

    Modifier and Type
    Method
    Description
    static ThreadLocalRandom
    current()
    Deprecated.
    Returns the current thread's ThreadLocalRandom.
    static long
    getInitialSeedUniquifier()
    Deprecated.
     
    private static long
    mix64(long z)
    Deprecated.
     
    private static long
    newSeed()
    Deprecated.
     
    protected int
    next(int bits)
    Deprecated.
     
    double
    nextDouble(double n)
    Deprecated.
    Returns a pseudorandom, uniformly distributed double value between 0 (inclusive) and the specified value (exclusive).
    double
    nextDouble(double least, double bound)
    Deprecated.
    Returns a pseudorandom, uniformly distributed value between the given least value (inclusive) and bound (exclusive).
    int
    nextInt(int least, int bound)
    Deprecated.
    Returns a pseudorandom, uniformly distributed value between the given least value (inclusive) and bound (exclusive).
    long
    nextLong(long n)
    Deprecated.
    Returns a pseudorandom, uniformly distributed value between 0 (inclusive) and the specified value (exclusive).
    long
    nextLong(long least, long bound)
    Deprecated.
    Returns a pseudorandom, uniformly distributed value between the given least value (inclusive) and bound (exclusive).
    static void
    setInitialSeedUniquifier(long initialSeedUniquifier)
    Deprecated.
     
    void
    setSeed(long seed)
    Deprecated.
    Throws UnsupportedOperationException.

    Methods inherited from class java.util.Random

    doubles, doubles, doubles, doubles, ints, ints, ints, ints, longs, longs, longs, longs, nextBoolean, nextBytes, nextDouble, nextFloat, nextGaussian, nextInt, nextInt, nextLong

    Methods inherited from class java.lang.Object

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

  • Field Details

    • logger

      private static final InternalLogger logger
      Deprecated.

    • seedUniquifier

      private static final java.util.concurrent.atomic.AtomicLong seedUniquifier
      Deprecated.

    • initialSeedUniquifier

      private static volatile long initialSeedUniquifier
      Deprecated.

    • seedGeneratorThread

      private static final java.lang.Thread seedGeneratorThread
      Deprecated.

    • seedQueue

      private static final java.util.concurrent.BlockingQueue<java.lang.Long> seedQueue
      Deprecated.

    • seedGeneratorStartTime

      private static final long seedGeneratorStartTime
      Deprecated.

    • seedGeneratorEndTime

      private static volatile long seedGeneratorEndTime
      Deprecated.

    • multiplier

      private static final long multiplier
      Deprecated.
      See Also:

    • addend

      private static final long addend
      Deprecated.
      See Also:

    • mask

      private static final long mask
      Deprecated.
      See Also:

    • rnd

      private long rnd
      Deprecated.
      The random seed. We can't use super.seed.

    • initialized

      boolean initialized
      Deprecated.
      Initialization flag to permit calls to setSeed to succeed only while executing the Random constructor. We can't allow others since it would cause setting seed in one part of a program to unintentionally impact other usages by the thread.

    • pad0

      private long pad0
      Deprecated.

    • pad1

      private long pad1
      Deprecated.

    • pad2

      private long pad2
      Deprecated.

    • pad3

      private long pad3
      Deprecated.

    • pad4

      private long pad4
      Deprecated.

    • pad5

      private long pad5
      Deprecated.

    • pad6

      private long pad6
      Deprecated.

    • pad7

      private long pad7
      Deprecated.

    • serialVersionUID

      private static final long serialVersionUID
      Deprecated.
      See Also:

  • Constructor Details

    • ThreadLocalRandom

      ThreadLocalRandom()
      Deprecated.
      Constructor called only by localRandom.initialValue.

  • Method Details

    • setInitialSeedUniquifier

      public static void setInitialSeedUniquifier(long initialSeedUniquifier)
      Deprecated.

    • getInitialSeedUniquifier

      public static long getInitialSeedUniquifier()
      Deprecated.

    • newSeed

      private static long newSeed()
      Deprecated.

    • mix64

      private static long mix64(long z)
      Deprecated.

    • current

      public static ThreadLocalRandom current()
      Deprecated.
      Returns the current thread's ThreadLocalRandom.
      Returns:
      the current thread's ThreadLocalRandom

    • setSeed

      public void setSeed(long seed)
      Deprecated.
      Throws UnsupportedOperationException. Setting seeds in this generator is not supported.
      Overrides:
      setSeed in class java.util.Random
      Throws:
      java.lang.UnsupportedOperationException - always

    • next

      protected int next(int bits)
      Deprecated.
      Overrides:
      next in class java.util.Random

    • nextInt

      public int nextInt(int least, int bound)
      Deprecated.
      Returns a pseudorandom, uniformly distributed value between the given least value (inclusive) and bound (exclusive).
      Parameters:
      least - the least value returned
      bound - the upper bound (exclusive)
      Returns:
      the next value
      Throws:
      java.lang.IllegalArgumentException - if least greater than or equal to bound

    • nextLong

      public long nextLong(long n)
      Deprecated.
      Returns a pseudorandom, uniformly distributed value between 0 (inclusive) and the specified value (exclusive).
      Parameters:
      n - the bound on the random number to be returned. Must be positive.
      Returns:
      the next value
      Throws:
      java.lang.IllegalArgumentException - if n is not positive

    • nextLong

      public long nextLong(long least, long bound)
      Deprecated.
      Returns a pseudorandom, uniformly distributed value between the given least value (inclusive) and bound (exclusive).
      Parameters:
      least - the least value returned
      bound - the upper bound (exclusive)
      Returns:
      the next value
      Throws:
      java.lang.IllegalArgumentException - if least greater than or equal to bound

    • nextDouble

      public double nextDouble(double n)
      Deprecated.
      Returns a pseudorandom, uniformly distributed double value between 0 (inclusive) and the specified value (exclusive).
      Parameters:
      n - the bound on the random number to be returned. Must be positive.
      Returns:
      the next value
      Throws:
      java.lang.IllegalArgumentException - if n is not positive

    • nextDouble

      public double nextDouble(double least, double bound)
      Deprecated.
      Returns a pseudorandom, uniformly distributed value between the given least value (inclusive) and bound (exclusive).
      Parameters:
      least - the least value returned
      bound - the upper bound (exclusive)
      Returns:
      the next value
      Throws:
      java.lang.IllegalArgumentException - if least greater than or equal to bound