java.util.concurrent.atomic
Class AtomicReference<V>

java.lang.Object
  java.util.concurrent.atomic.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

AtomicReference()
Create a new AtomicReference with null initial value.

AtomicReference(V initialValue)
Create a new AtomicReference with the given initial value.

Method Summary

boolean	compareAndSet(V expect, V update) Atomically set the value to the given updated value if the current value == the expected value.
V	get() Get the current value.
V	getAndSet(V newValue) Set to the given value and return the old value.
void	set(V newValue) Set to the given value.
String	toString() Returns the String representation of the current value.
boolean	weakCompareAndSet(V expect, V update) Atomically set the value to the given updated value if the current value == the expected value.

Methods inherited from class java.lang.Object

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

Constructor Detail

AtomicReference

public AtomicReference(V initialValue)

Create a new AtomicReference with the given initial value.

Parameters:

initialValue - the initial value

AtomicReference

public AtomicReference()

Create a new AtomicReference with null initial value.

Method Detail

get

public final V get()

Get the current value.

Returns:

the current value

set

public final void set(V newValue)

Set to the given value.

Parameters:

newValue - the new value

compareAndSet

public final boolean compareAndSet(V expect,
                                   V update)

Atomically set 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 set the value to the given updated value if the current value == the expected value. May fail spuriously.

Parameters:

expect - the expected value

update - the new value

Returns:

true if successful.

getAndSet

public final V getAndSet(V newValue)

Set to the given value and return 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.