Package java.util.concurrent.atomic

Class AtomicReference<V>

  • Type Parameters:
    V - The type of object referred to by this reference
    All Implemented Interfaces:
    Serializable
    public class AtomicReference<V>
extends Object
implements Serializable
    An object reference that may be updated atomically. See the java.util.concurrent.atomic package specification for description of the properties of atomic variables.
    Since:
    1.5
    See Also:
    Serialized Form

    • Constructor Summary

      Constructors 
      Constructor Description
      AtomicReference()
      Creates a new AtomicReference with null initial value.
      AtomicReference​(V initialValue)
      Creates a new AtomicReference with the given initial value.

    • Constructor Detail

      • AtomicReference

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

      • AtomicReference

        public AtomicReference()
        Creates a new AtomicReference with null initial value.

    • Method Detail

      • get

        public final V get()
        Gets the current value.
        Returns:
        the current value

      • set

        public final void set​(V newValue)
        Sets to the given value.
        Parameters:
        newValue - the new value

      • lazySet

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

      • compareAndSet

        public final boolean compareAndSet​(V expect,
                                   V 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 final boolean weakCompareAndSet​(V expect,
                                       V 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

      • getAndSet

        public final V getAndSet​(V newValue)
        Atomically sets to the given value and returns the old 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