19 |
|
* this class does extend {@code Number} to allow uniform access by |
20 |
|
* tools and utilities that deal with numerically-based classes. |
21 |
|
* |
22 |
< |
* <p><a name="bitEquals">This class compares primitive {@code double} |
22 |
> |
* <p id="bitEquals">This class compares primitive {@code double} |
23 |
|
* values in methods such as {@link #compareAndSet} by comparing their |
24 |
|
* bitwise representation using {@link Double#doubleToRawLongBits}, |
25 |
|
* which differs from both the primitive double {@code ==} operator |
26 |
|
* and from {@link Double#equals}, as if implemented by: |
27 |
|
* <pre> {@code |
28 |
< |
* boolean bitEquals(double x, double y) { |
28 |
> |
* static boolean bitEquals(double x, double y) { |
29 |
|
* long xBits = Double.doubleToRawLongBits(x); |
30 |
|
* long yBits = Double.doubleToRawLongBits(y); |
31 |
|
* return xBits == yBits; |
40 |
|
public class AtomicDouble extends Number implements java.io.Serializable { |
41 |
|
private static final long serialVersionUID = -8405198993435143622L; |
42 |
|
|
43 |
< |
private volatile long value; |
43 |
> |
private transient volatile long value; |
44 |
|
|
45 |
|
/** |
46 |
|
* Creates a new {@code AtomicDouble} with the given initial value. |
210 |
|
return get(); |
211 |
|
} |
212 |
|
|
213 |
+ |
/** |
214 |
+ |
* Saves the state to a stream (that is, serializes it). |
215 |
+ |
* |
216 |
+ |
* @serialData The current value is emitted (a {@code double}). |
217 |
+ |
*/ |
218 |
+ |
private void writeObject(java.io.ObjectOutputStream s) |
219 |
+ |
throws java.io.IOException { |
220 |
+ |
s.defaultWriteObject(); |
221 |
+ |
|
222 |
+ |
s.writeDouble(get()); |
223 |
+ |
} |
224 |
+ |
|
225 |
+ |
/** |
226 |
+ |
* Reconstitutes the instance from a stream (that is, deserializes it). |
227 |
+ |
*/ |
228 |
+ |
private void readObject(java.io.ObjectInputStream s) |
229 |
+ |
throws java.io.IOException, ClassNotFoundException { |
230 |
+ |
s.defaultReadObject(); |
231 |
+ |
|
232 |
+ |
set(s.readDouble()); |
233 |
+ |
} |
234 |
+ |
|
235 |
|
// Unsafe mechanics |
236 |
|
private static final sun.misc.Unsafe unsafe = getUnsafe(); |
237 |
|
private static final long valueOffset; |
253 |
|
private static sun.misc.Unsafe getUnsafe() { |
254 |
|
try { |
255 |
|
return sun.misc.Unsafe.getUnsafe(); |
256 |
< |
} catch (SecurityException se) { |
257 |
< |
try { |
258 |
< |
return java.security.AccessController.doPrivileged |
259 |
< |
(new java.security |
260 |
< |
.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
261 |
< |
public sun.misc.Unsafe run() throws Exception { |
262 |
< |
java.lang.reflect.Field f = sun.misc |
263 |
< |
.Unsafe.class.getDeclaredField("theUnsafe"); |
264 |
< |
f.setAccessible(true); |
265 |
< |
return (sun.misc.Unsafe) f.get(null); |
266 |
< |
}}); |
267 |
< |
} catch (java.security.PrivilegedActionException e) { |
268 |
< |
throw new RuntimeException("Could not initialize intrinsics", |
269 |
< |
e.getCause()); |
270 |
< |
} |
256 |
> |
} catch (SecurityException tryReflectionInstead) {} |
257 |
> |
try { |
258 |
> |
return java.security.AccessController.doPrivileged |
259 |
> |
(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
260 |
> |
public sun.misc.Unsafe run() throws Exception { |
261 |
> |
Class<sun.misc.Unsafe> k = sun.misc.Unsafe.class; |
262 |
> |
for (java.lang.reflect.Field f : k.getDeclaredFields()) { |
263 |
> |
f.setAccessible(true); |
264 |
> |
Object x = f.get(null); |
265 |
> |
if (k.isInstance(x)) |
266 |
> |
return k.cast(x); |
267 |
> |
} |
268 |
> |
throw new NoSuchFieldError("the Unsafe"); |
269 |
> |
}}); |
270 |
> |
} catch (java.security.PrivilegedActionException e) { |
271 |
> |
throw new RuntimeException("Could not initialize intrinsics", |
272 |
> |
e.getCause()); |
273 |
|
} |
274 |
|
} |
275 |
|
} |