Java compact1, compact2, compact3 java.util.concurrent.atomic Class AtomicMarkableReference<V>（JDK8）

Constructor Detail

• AtomicMarkableReference

  public AtomicMarkableReference(V initialRef,
                                 boolean initialMark)

  Creates a new AtomicMarkableReference with the given initial values.

  Parameters:

  initialRef - the initial reference

  initialMark - the initial mark

Method Detail

• getReference

  public V getReference()

  Returns the current value of the reference.

  Returns:

  the current value of the reference

• isMarked

  public boolean isMarked()

  Returns the current value of the mark.

  Returns:

  the current value of the mark

• get

  public V get(boolean[] markHolder)

  Returns the current values of both the reference and the mark. Typical usage is boolean[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

• weakCompareAndSet

  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 == 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:

  true if successful

• compareAndSet

  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 == 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:

  true if successful

• set

  public 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

• attemptMark

  public 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 (return 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.

  Parameters:

  expectedReference - the expected value of the reference

  newMark - the new value for the mark

  Returns:

  true if successful