This class compares primitive {@code double}
+ * 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:
*
{@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;
@@ -40,7 +40,7 @@ import static java.lang.Double.longBitsT
public class AtomicDouble extends Number implements java.io.Serializable {
private static final long serialVersionUID = -8405198993435143622L;
- private volatile long value;
+ private transient volatile long value;
/**
* Creates a new {@code AtomicDouble} with the given initial value.
@@ -210,6 +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;
@@ -231,21 +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() {
- 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() {
+ public sun.misc.Unsafe run() throws Exception {
+ Class 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());
}
}
}