Package edu.rit.pj.reduction

Class SharedByte

java.lang.Object
java.lang.Number
edu.rit.pj.reduction.SharedByte
All Implemented Interfaces:
Serializable
public class SharedByte extends Number
Class SharedByte provides a reduction variable for a value of type byte.

Class SharedByte is multiple thread safe. The methods use lock-free atomic compare-and-set.

Note: Class SharedByte is implemented using class java.util.concurrent.atomic.AtomicInteger. The byte value is stored as an int whose values are restricted to the range of type byte.

Version:
07-Jun-2007
Author:
Alan Kaminsky
See Also:

  • Constructor Summary

    Constructors
    Constructor
    Description
    SharedByte()
    Construct a new byte reduction variable with the initial value 0.
    SharedByte(byte initialValue)
    Construct a new byte reduction variable with the given initial value.

  • Method Summary

    Modifier and Type
    Method
    Description
    byte
    addAndGet(byte value)
    Add the given value to this reduction variable and return the new value.
    boolean
    compareAndSet(byte expect, byte update)
    Atomically set this reduction variable to the given updated value if the current value equals the expected value.
    byte
    decrementAndGet()
    Subtract one from this reduction variable and return the new value.
    double
    doubleValue()
    Returns this reduction variable's current value converted to type double.
    float
    floatValue()
    Returns this reduction variable's current value converted to type float.
    byte
    get()
    Returns this reduction variable's current value.
    byte
    getAndAdd(byte value)
    Add the given value to this reduction variable and return the previous value.
    byte
    getAndDecrement()
    Subtract one from this reduction variable and return the previous value.
    byte
    getAndIncrement()
    Add one to this reduction variable and return the previous value.
    byte
    getAndSet(byte value)
    Set this reduction variable to the given value and return the previous value.
    byte
    incrementAndGet()
    Add one to this reduction variable and return the new value.
    int
    intValue()
    Returns this reduction variable's current value converted to type int.
    long
    longValue()
    Returns this reduction variable's current value converted to type long.
    byte
    reduce(byte value, ByteOp op)
    Combine this reduction variable with the given value using the given operation.
    void
    set(byte value)
    Set this reduction variable to the given value.
    String
    toString()
    Returns a string version of this reduction variable.
    boolean
    weakCompareAndSet(byte expect, byte update)
    Atomically set this reduction variable to the given updated value if the current value equals the expected value.

    Methods inherited from class java.lang.Number

    byteValue, shortValue

    Methods inherited from class java.lang.Object

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

  • Constructor Details

    • SharedByte

      public SharedByte()
      Construct a new byte reduction variable with the initial value 0.

    • SharedByte

      public SharedByte(byte initialValue)
      Construct a new byte reduction variable with the given initial value.
      Parameters:
      initialValue - Initial value.

  • Method Details

    • get

      public byte get()
      Returns this reduction variable's current value.
      Returns:
      Current value.

    • set

      public void set(byte value)
      Set this reduction variable to the given value.
      Parameters:
      value - New value.

    • getAndSet

      public byte getAndSet(byte value)
      Set this reduction variable to the given value and return the previous value.
      Parameters:
      value - New value.
      Returns:
      Previous value.

    • compareAndSet

      public boolean compareAndSet(byte expect, byte update)
      Atomically set this reduction variable to the given updated value if the current value equals the expected value.
      Parameters:
      expect - Expected value.
      update - Updated value.
      Returns:
      True if the update happened, false otherwise.

    • weakCompareAndSet

      public boolean weakCompareAndSet(byte expect, byte update)
      Atomically set this reduction variable to the given updated value if the current value equals the expected value. May fail spuriously.
      Parameters:
      expect - Expected value.
      update - Updated value.
      Returns:
      True if the update happened, false otherwise.

    • getAndIncrement

      public byte getAndIncrement()
      Add one to this reduction variable and return the previous value.
      Returns:
      Previous value.

    • getAndDecrement

      public byte getAndDecrement()
      Subtract one from this reduction variable and return the previous value.
      Returns:
      Previous value.

    • getAndAdd

      public byte getAndAdd(byte value)
      Add the given value to this reduction variable and return the previous value.
      Parameters:
      value - Value to add.
      Returns:
      Previous value.

    • incrementAndGet

      public byte incrementAndGet()
      Add one to this reduction variable and return the new value.
      Returns:
      New value.

    • decrementAndGet

      public byte decrementAndGet()
      Subtract one from this reduction variable and return the new value.
      Returns:
      New value.

    • addAndGet

      public byte addAndGet(byte value)
      Add the given value to this reduction variable and return the new value.
      Parameters:
      value - Value to add.
      Returns:
      New value.

    • reduce

      public byte reduce(byte value, ByteOp op)
      Combine this reduction variable with the given value using the given operation. The result is stored back into this reduction variable and is returned.
      Parameters:
      value - Value.
      op - Binary operation.
      Returns:
      (This variable) op (value).

    • toString

      public String toString()
      Returns a string version of this reduction variable.
      Overrides:
      toString in class Object
      Returns:
      String version.

    • intValue

      public int intValue()
      Returns this reduction variable's current value converted to type int.
      Specified by:
      intValue in class Number
      Returns:
      Current value.

    • longValue

      public long longValue()
      Returns this reduction variable's current value converted to type long.
      Specified by:
      longValue in class Number
      Returns:
      Current value.

    • floatValue

      public float floatValue()
      Returns this reduction variable's current value converted to type float.
      Specified by:
      floatValue in class Number
      Returns:
      Current value.

    • doubleValue

      public double doubleValue()
      Returns this reduction variable's current value converted to type double.
      Specified by:
      doubleValue in class Number
      Returns:
      Current value.