File	Doc	Category	Size	Date	Package
AtomicMarkableReference.java	API Doc	Java SE 6 API	6337	Tue Jun 10 00:25:58 BST 2008	java.util.concurrent.atomic

AtomicMarkableReference

• java.lang.Object

Fields Summary
private final AtomicReference	atomicRef

Constructors Summary
public AtomicMarkableReference(V initialRef, boolean initialMark) Creates a new {@code AtomicMarkableReference} with the given initial values. param initialRef the initial reference param initialMark the initial mark atomicRef = new AtomicReference<ReferenceBooleanPair<V>> (new ReferenceBooleanPair<V>(initialRef, initialMark));

Methods Summary
public boolean	attemptMark(V expectedReference, boolean newMark) Atomically sets the value of the mark to the given update value if the current reference is {@code ==} to the expected reference. Any given invocation of this operation may fail (return {@code false}) spuriously, but repeated invocation when the current value holds the expected value and no other thread is also attempting to set the value will eventually succeed. param expectedReference the expected value of the reference param newMark the new value for the mark return true if successful ReferenceBooleanPair<V> current = atomicRef.get(); return expectedReference == current.reference && (newMark == current.bit || atomicRef.compareAndSet (current, new ReferenceBooleanPair<V>(expectedReference, newMark)));
public boolean	compareAndSet(V expectedReference, V newReference, boolean expectedMark, boolean newMark) Atomically sets the value of both the reference and mark to the given update values if the current reference is {@code ==} to the expected reference and the current mark is equal to the expected mark. param expectedReference the expected value of the reference param newReference the new value for the reference param expectedMark the expected value of the mark param newMark the new value for the mark return true if successful ReferenceBooleanPair<V> current = atomicRef.get(); return expectedReference == current.reference && expectedMark == current.bit && ((newReference == current.reference && newMark == current.bit) || atomicRef.compareAndSet(current, new ReferenceBooleanPair<V>(newReference, newMark)));
public V	get(boolean[] markHolder) Returns the current values of both the reference and the mark. Typical usage is {@code boolean[1] holder; ref = v.get(holder); }. param markHolder an array of size of at least one. On return, {@code markholder[0]} will hold the value of the mark. return the current value of the reference ReferenceBooleanPair<V> p = atomicRef.get(); markHolder[0] = p.bit; return p.reference;
public V	getReference() Returns the current value of the reference. return the current value of the reference return atomicRef.get().reference;
public boolean	isMarked() Returns the current value of the mark. return the current value of the mark return atomicRef.get().bit;
public void	set(V newReference, boolean newMark) Unconditionally sets the value of both the reference and mark. param newReference the new value for the reference param newMark the new value for the mark ReferenceBooleanPair<V> current = atomicRef.get(); if (newReference != current.reference || newMark != current.bit) atomicRef.set(new ReferenceBooleanPair<V>(newReference, newMark));
public boolean	weakCompareAndSet(V expectedReference, V newReference, boolean expectedMark, boolean newMark) Atomically sets the value of both the reference and mark to the given update values if the current reference is {@code ==} to the expected reference and the current mark is equal to the expected mark. May fail spuriously and does not provide ordering guarantees, so is only rarely an appropriate alternative to {@code compareAndSet}. param expectedReference the expected value of the reference param newReference the new value for the reference param expectedMark the expected value of the mark param newMark the new value for the mark return true if successful ReferenceBooleanPair<V> current = atomicRef.get(); return expectedReference == current.reference && expectedMark == current.bit && ((newReference == current.reference && newMark == current.bit) || atomicRef.weakCompareAndSet(current, new ReferenceBooleanPair<V>(newReference, newMark)));