- java.lang.Object
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- java.util.concurrent.atomic.AtomicMarkableReference<V>
 
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- Type Parameters:
- V- The type of object referred to by this reference
 
 public class AtomicMarkableReference<V> extends Object AnAtomicMarkableReferencemaintains an object reference along with a mark bit, that can be updated atomically.Implementation note: This implementation maintains markable references by creating internal objects representing "boxed" [reference, boolean] pairs. - Since:
- 1.5
 
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Constructor SummaryConstructors Constructor Description AtomicMarkableReference(V initialRef, boolean initialMark)Creates a newAtomicMarkableReferencewith the given initial values.
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Method SummaryAll Methods Instance Methods Concrete Methods Modifier and Type Method Description booleanattemptMark(V expectedReference, boolean newMark)Atomically sets the value of the mark to the given update value if the current reference is==to the expected reference.booleancompareAndSet(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==to the expected reference and the current mark is equal to the expected mark.Vget(boolean[] markHolder)Returns the current values of both the reference and the mark.VgetReference()Returns the current value of the reference.booleanisMarked()Returns the current value of the mark.voidset(V newReference, boolean newMark)Unconditionally sets the value of both the reference and mark.booleanweakCompareAndSet(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==to the expected reference and the current mark is equal to the expected mark.
 
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Constructor Detail- 
AtomicMarkableReferencepublic AtomicMarkableReference(V initialRef, boolean initialMark) Creates a newAtomicMarkableReferencewith the given initial values.- Parameters:
- initialRef- the initial reference
- initialMark- the initial mark
 
 
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Method Detail- 
getReferencepublic V getReference() Returns the current value of the reference.- Returns:
- the current value of the reference
 
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isMarkedpublic boolean isMarked() Returns the current value of the mark.- Returns:
- the current value of the mark
 
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getpublic V get(boolean[] markHolder) Returns the current values of both the reference and the mark. Typical usage isboolean[1] holder; ref = v.get(holder);.- Parameters:
- markHolder- an array of size of at least one. On return,- markHolder[0]will hold the value of the mark.
- Returns:
- the current value of the reference
 
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weakCompareAndSetpublic 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==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 compareAndSet.- Parameters:
- expectedReference- the expected value of the reference
- newReference- the new value for the reference
- expectedMark- the expected value of the mark
- newMark- the new value for the mark
- Returns:
- trueif successful
 
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compareAndSetpublic 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==to the expected reference and the current mark is equal to the expected mark.- Parameters:
- expectedReference- the expected value of the reference
- newReference- the new value for the reference
- expectedMark- the expected value of the mark
- newMark- the new value for the mark
- Returns:
- trueif successful
 
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setpublic void set(V newReference, boolean newMark) Unconditionally sets the value of both the reference and mark.- Parameters:
- newReference- the new value for the reference
- newMark- the new value for the mark
 
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attemptMarkpublic boolean attemptMark(V expectedReference, boolean newMark) Atomically sets the value of the mark to the given update value if the current reference is==to the expected reference. Any given invocation of this operation may fail (returnfalse) 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.- Parameters:
- expectedReference- the expected value of the reference
- newMark- the new value for the mark
- Returns:
- trueif successful
 
 
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