--- jsr166/src/jsr166e/extra/AtomicDouble.java	2011/08/10 01:29:45	1.5
+++ jsr166/src/jsr166e/extra/AtomicDouble.java	2013/03/04 15:21:23	1.16
@@ -19,28 +19,31 @@ import static java.lang.Double.longBitsT
  * this class does extend {@code Number} to allow uniform access by
  * tools and utilities that deal with numerically-based classes.
  *
- * <p><a name="bitEquals">This class compares primitive {@code double}
+ * <p id="bitEquals">This class compares primitive {@code double}
  * values in methods such as {@link #compareAndSet} by comparing their
  * bitwise representation using {@link Double#doubleToRawLongBits},
  * which differs from both the primitive double {@code ==} operator
  * and from {@link Double#equals}, as if implemented by:
  *  <pre> {@code
- * boolean bitEquals(double x, double y) {
+ * static boolean bitEquals(double x, double y) {
  *   long xBits = Double.doubleToRawLongBits(x);
  *   long yBits = Double.doubleToRawLongBits(y);
  *   return xBits == yBits;
  * }}</pre>
  *
+ * @see jsr166e.DoubleAdder
+ * @see jsr166e.DoubleMaxUpdater
+ *
  * @author Doug Lea
  * @author Martin Buchholz
  */
 public class AtomicDouble extends Number implements java.io.Serializable {
-    static final long serialVersionUID = -8405198993435143622L;
+    private static final long serialVersionUID = -8405198993435143622L;
 
-    private volatile long value;
+    private transient volatile long value;
 
     /**
-     * Creates a new AtomicDouble with the given initial value.
+     * Creates a new {@code AtomicDouble} with the given initial value.
      *
      * @param initialValue the initial value
      */
@@ -49,9 +52,11 @@ public class AtomicDouble extends Number
     }
 
     /**
-     * Creates a new AtomicDouble with initial value {@code 0.0}.
+     * Creates a new {@code AtomicDouble} with initial value {@code 0.0}.
      */
-    public AtomicDouble() { this(0.0); }
+    public AtomicDouble() {
+        // assert doubleToRawLongBits(0.0) == 0L;
+    }
 
     /**
      * Gets the current value.
@@ -118,7 +123,9 @@ public class AtomicDouble extends Number
      * if the current value is <a href="#bitEquals">bitwise equal</a>
      * to the expected value.
      *
-     * <p>May <a href="package-summary.html#Spurious">fail spuriously</a>
+     * <p>May <a
+     * href="http://download.oracle.com/javase/7/docs/api/java/util/concurrent/atomic/package-summary.html#Spurious">
+     * fail spuriously</a>
      * and does not provide ordering guarantees, so is only rarely an
      * appropriate alternative to {@code compareAndSet}.
      *
@@ -177,7 +184,7 @@ public class AtomicDouble extends Number
      * after a narrowing primitive conversion.
      */
     public int intValue() {
-        return (int)get();
+        return (int) get();
     }
 
     /**
@@ -185,7 +192,7 @@ public class AtomicDouble extends Number
      * after a narrowing primitive conversion.
      */
     public long longValue() {
-        return (long)get();
+        return (long) get();
     }
 
     /**
@@ -193,7 +200,7 @@ public class AtomicDouble extends Number
      * after a narrowing primitive conversion.
      */
     public float floatValue() {
-        return (float)get();
+        return (float) get();
     }
 
     /**
@@ -203,6 +210,28 @@ public class AtomicDouble extends Number
         return get();
     }
 
+    /**
+     * Saves the state to a stream (that is, serializes it).
+     *
+     * @serialData The current value is emitted (a {@code double}).
+     */
+    private void writeObject(java.io.ObjectOutputStream s)
+        throws java.io.IOException {
+        s.defaultWriteObject();
+
+        s.writeDouble(get());
+    }
+
+    /**
+     * Reconstitutes the instance from a stream (that is, deserializes it).
+     */
+    private void readObject(java.io.ObjectInputStream s)
+        throws java.io.IOException, ClassNotFoundException {
+        s.defaultReadObject();
+
+        set(s.readDouble());
+    }
+
     // Unsafe mechanics
     private static final sun.misc.Unsafe unsafe = getUnsafe();
     private static final long valueOffset;
@@ -224,22 +253,23 @@ public class AtomicDouble extends Number
     private static sun.misc.Unsafe getUnsafe() {
         try {
             return sun.misc.Unsafe.getUnsafe();
-        } catch (SecurityException se) {
-            try {
-                return java.security.AccessController.doPrivileged
-                    (new java.security
-                     .PrivilegedExceptionAction<sun.misc.Unsafe>() {
-                        public sun.misc.Unsafe run() throws Exception {
-                            java.lang.reflect.Field f = sun.misc
-                                .Unsafe.class.getDeclaredField("theUnsafe");
-                            f.setAccessible(true);
-                            return (sun.misc.Unsafe) f.get(null);
-                        }});
-            } catch (java.security.PrivilegedActionException e) {
-                throw new RuntimeException("Could not initialize intrinsics",
-                                           e.getCause());
-            }
+        } catch (SecurityException tryReflectionInstead) {}
+        try {
+            return java.security.AccessController.doPrivileged
+            (new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() {
+                public sun.misc.Unsafe run() throws Exception {
+                    Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class;
+                    for (java.lang.reflect.Field f : k.getDeclaredFields()) {
+                        f.setAccessible(true);
+                        Object x = f.get(null);
+                        if (k.isInstance(x))
+                            return k.cast(x);
+                    }
+                    throw new NoSuchFieldError("the Unsafe");
+                }});
+        } catch (java.security.PrivilegedActionException e) {
+            throw new RuntimeException("Could not initialize intrinsics",
+                                       e.getCause());
         }
     }
-
 }