Module java.base

Class AtomicBoolean

  • All Implemented Interfaces:
    Serializable


    public class AtomicBoolean
    extends Object
    implements Serializable
    A boolean value that may be updated atomically. See the VarHandle specification for descriptions of the properties of atomic accesses. An AtomicBoolean is used in applications such as atomically updated flags, and cannot be used as a replacement for a Boolean.
    Since:
    1.5
    Author:
    Doug Lea
    See Also:
    Serialized Form
    • 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

      • compareAndSet

        public final boolean compareAndSet​(boolean expectedValue,
                                           boolean newValue)
        Atomically sets the value to newValue if the current value == expectedValue, with memory effects as specified by VarHandle.compareAndSet(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        true if successful. False return indicates that the actual value was not equal to the expected value.
      • weakCompareAndSetPlain

        public boolean weakCompareAndSetPlain​(boolean expectedValue,
                                              boolean newValue)
        Possibly atomically sets the value to newValue if the current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetPlain(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        true if successful
        Since:
        9
      • lazySet

        public final void lazySet​(boolean newValue)
        Sets the value to newValue, with memory effects as specified by VarHandle.setRelease(java.lang.Object...).
        Parameters:
        newValue - the new value
        Since:
        1.6
      • getAndSet

        public final boolean getAndSet​(boolean newValue)
        Atomically sets the value to newValue and returns the old value, with memory effects as specified by VarHandle.getAndSet(java.lang.Object...).
        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
      • getPlain

        public final boolean getPlain​()
        Returns the current value, with memory semantics of reading as if the variable was declared non-volatile.
        Returns:
        the value
        Since:
        9
      • setPlain

        public final void setPlain​(boolean newValue)
        Sets the value to newValue, with memory semantics of setting as if the variable was declared non-volatile and non-final.
        Parameters:
        newValue - the new value
        Since:
        9
      • setOpaque

        public final void setOpaque​(boolean newValue)
        Sets the value to newValue, with memory effects as specified by VarHandle.setOpaque(java.lang.Object...).
        Parameters:
        newValue - the new value
        Since:
        9
      • setRelease

        public final void setRelease​(boolean newValue)
        Sets the value to newValue, with memory effects as specified by VarHandle.setRelease(java.lang.Object...).
        Parameters:
        newValue - the new value
        Since:
        9
      • compareAndExchange

        public final boolean compareAndExchange​(boolean expectedValue,
                                                boolean newValue)
        Atomically sets the value to newValue if the current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchange(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        the witness value, which will be the same as the expected value if successful
        Since:
        9
      • compareAndExchangeAcquire

        public final boolean compareAndExchangeAcquire​(boolean expectedValue,
                                                       boolean newValue)
        Atomically sets the value to newValue if the current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchangeAcquire(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        the witness value, which will be the same as the expected value if successful
        Since:
        9
      • compareAndExchangeRelease

        public final boolean compareAndExchangeRelease​(boolean expectedValue,
                                                       boolean newValue)
        Atomically sets the value to newValue if the current value, referred to as the witness value, == expectedValue, with memory effects as specified by VarHandle.compareAndExchangeRelease(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        the witness value, which will be the same as the expected value if successful
        Since:
        9
      • weakCompareAndSetVolatile

        public final boolean weakCompareAndSetVolatile​(boolean expectedValue,
                                                       boolean newValue)
        Possibly atomically sets the value to newValue if the current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSet(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        true if successful
        Since:
        9
      • weakCompareAndSetAcquire

        public final boolean weakCompareAndSetAcquire​(boolean expectedValue,
                                                      boolean newValue)
        Possibly atomically sets the value to newValue if the current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetAcquire(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        true if successful
        Since:
        9
      • weakCompareAndSetRelease

        public final boolean weakCompareAndSetRelease​(boolean expectedValue,
                                                      boolean newValue)
        Possibly atomically sets the value to newValue if the current value == expectedValue, with memory effects as specified by VarHandle.weakCompareAndSetRelease(java.lang.Object...).
        Parameters:
        expectedValue - the expected value
        newValue - the new value
        Returns:
        true if successful
        Since:
        9