Package java.util.concurrent.atomic

Class AtomicBoolean

  • All Implemented Interfaces:
    Serializable
    public class AtomicBoolean
extends Object
implements Serializable
    A boolean value that may be updated atomically. See the java.util.concurrent.atomic package specification for description of the properties of atomic variables. An AtomicBoolean is used in applications such as atomically updated flags, and cannot be used as a replacement for a Boolean.
    Since:
    1.5
    See Also:
    Serialized Form

    • Constructor Summary

      Constructors 
      Constructor Description
      AtomicBoolean()
      Creates a new AtomicBoolean with initial value false.
      AtomicBoolean​(boolean initialValue)
      Creates a new AtomicBoolean with the given initial value.

    • Method Summary

      All Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      boolean compareAndSet​(boolean expect, boolean update)
      Atomically sets the value to the given updated value if the current value == the expected value.
      boolean get()
      Returns the current value.
      boolean getAndSet​(boolean newValue)
      Atomically sets to the given value and returns the previous value.
      void lazySet​(boolean newValue)
      Eventually sets to the given value.
      void set​(boolean newValue)
      Unconditionally sets to the given value.
      String toString()
      Returns the String representation of the current value.
      boolean weakCompareAndSet​(boolean expect, boolean update)
      Atomically sets the value to the given updated value if the current value == the expected value.

    • Constructor Detail

      • AtomicBoolean

        public AtomicBoolean​(boolean initialValue)
        Creates a new AtomicBoolean with the given initial value.
        Parameters:
        initialValue - the initial value

      • AtomicBoolean

        public AtomicBoolean()
        Creates a new AtomicBoolean with initial value false.

    • Method Detail

      • get

        public final boolean get()
        Returns the current value.
        Returns:
        the current value

      • compareAndSet

        public final boolean compareAndSet​(boolean expect,
                                   boolean update)
        Atomically sets the value to the given updated value if the current value == the expected value.
        Parameters:
        expect - the expected value
        update - the new value
        Returns:
        true if successful. False return indicates that the actual value was not equal to the expected value.

      • weakCompareAndSet

        public boolean weakCompareAndSet​(boolean expect,
                                 boolean update)
        Atomically sets the value to the given updated value if the current value == the expected value.

        May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to compareAndSet.

        Parameters:
        expect - the expected value
        update - the new value
        Returns:
        true if successful

      • set

        public final void set​(boolean newValue)
        Unconditionally sets to the given value.
        Parameters:
        newValue - the new value

      • lazySet

        public final void lazySet​(boolean newValue)
        Eventually sets to the given value.
        Parameters:
        newValue - the new value
        Since:
        1.6

      • getAndSet

        public final boolean getAndSet​(boolean newValue)
        Atomically sets to the given value and returns the previous value.
        Parameters:
        newValue - the new value
        Returns:
        the previous value

      • toString

        public String toString()
        Returns the String representation of the current value.
        Overrides:
        toString in class Object
        Returns:
        the String representation of the current value