src/share/classes/java/util/concurrent/atomic/AtomicReferenceFieldUpdater.java

*** 114,124 ****
       * necessarily with respect to other changes in the field.
       *
       * @param obj An object whose field to conditionally set
       * @param expect the expected value
       * @param update the new value
!      * @return true if successful.
       */
      public abstract boolean compareAndSet(T obj, V expect, V update);
  
      /**
       * Atomically sets the field of the given object managed by this updater
--- 114,124 ----
       * necessarily with respect to other changes in the field.
       *
       * @param obj An object whose field to conditionally set
       * @param expect the expected value
       * @param update the new value
!      * @return true if successful
       */
      public abstract boolean compareAndSet(T obj, V expect, V update);
  
      /**
       * Atomically sets the field of the given object managed by this updater
*** 132,142 ****
       * appropriate alternative to {@code compareAndSet}.
       *
       * @param obj An object whose field to conditionally set
       * @param expect the expected value
       * @param update the new value
!      * @return true if successful.
       */
      public abstract boolean weakCompareAndSet(T obj, V expect, V update);
  
      /**
       * Sets the field of the given object managed by this updater to the
--- 132,142 ----
       * appropriate alternative to {@code compareAndSet}.
       *
       * @param obj An object whose field to conditionally set
       * @param expect the expected value
       * @param update the new value
!      * @return true if successful
       */
      public abstract boolean weakCompareAndSet(T obj, V expect, V update);
  
      /**
       * Sets the field of the given object managed by this updater to the
*** 174,189 ****
       * @param obj An object whose field to get and set
       * @param newValue the new value
       * @return the previous value
       */
      public V getAndSet(T obj, V newValue) {
!         for (;;) {
!             V current = get(obj);
!             if (compareAndSet(obj, current, newValue))
!                 return current;
          }
-     }
  
      private static final class AtomicReferenceFieldUpdaterImpl<T,V>
          extends AtomicReferenceFieldUpdater<T,V> {
          private static final Unsafe unsafe = Unsafe.getUnsafe();
          private final long offset;
--- 174,189 ----
       * @param obj An object whose field to get and set
       * @param newValue the new value
       * @return the previous value
       */
      public V getAndSet(T obj, V newValue) {
!         V prev;
!         do {
!             prev = get(obj);
!         } while (!compareAndSet(obj, prev, newValue));
!         return prev;
      }
  
      private static final class AtomicReferenceFieldUpdaterImpl<T,V>
          extends AtomicReferenceFieldUpdater<T,V> {
          private static final Unsafe unsafe = Unsafe.getUnsafe();
          private final long offset;
*** 319,328 ****
--- 319,337 ----
              if (obj == null || obj.getClass() != tclass || cclass != null)
                  targetCheck(obj);
              return (V)unsafe.getObjectVolatile(obj, offset);
          }
  
+         @SuppressWarnings("unchecked")
+         public V getAndSet(T obj, V newValue) {
+             if (obj == null || obj.getClass() != tclass || cclass != null ||
+                 (newValue != null && vclass != null &&
+                  vclass != newValue.getClass()))
+                 updateCheck(obj, newValue);
+             return (V)unsafe.getAndSetObject(obj, offset, newValue);
+         }
+ 
          private void ensureProtectedAccess(T obj) {
              if (cclass.isInstance(obj)) {
                  return;
              }
              throw new RuntimeException(