| 14 |
|
import java.util.NoSuchElementException; |
| 15 |
|
import java.util.concurrent.locks.LockSupport; |
| 16 |
|
import java.util.concurrent.atomic.AtomicReference; |
| 17 |
– |
import java.util.concurrent.atomic.AtomicReferenceFieldUpdater; |
| 17 |
|
|
| 18 |
|
/** |
| 19 |
|
* An unbounded {@linkplain TransferQueue} based on linked nodes. |
| 114 |
|
this.isData = isData; |
| 115 |
|
} |
| 116 |
|
|
| 118 |
– |
@SuppressWarnings("rawtypes") |
| 119 |
– |
static final AtomicReferenceFieldUpdater<Node, Node> |
| 120 |
– |
nextUpdater = AtomicReferenceFieldUpdater.newUpdater |
| 121 |
– |
(Node.class, Node.class, "next"); |
| 122 |
– |
|
| 117 |
|
final boolean casNext(Node<E> cmp, Node<E> val) { |
| 118 |
< |
return nextUpdater.compareAndSet(this, cmp, val); |
| 118 |
> |
return UNSAFE.compareAndSwapObject(this, nextOffset, cmp, val); |
| 119 |
|
} |
| 120 |
|
|
| 121 |
|
final void clearNext() { |
| 122 |
< |
nextUpdater.lazySet(this, this); |
| 122 |
> |
UNSAFE.putOrderedObject(this, nextOffset, this); |
| 123 |
> |
} |
| 124 |
> |
|
| 125 |
> |
// Unsafe mechanics |
| 126 |
> |
|
| 127 |
> |
private static final sun.misc.Unsafe UNSAFE = getUnsafe(); |
| 128 |
> |
private static final long nextOffset = |
| 129 |
> |
objectFieldOffset(UNSAFE, "next", Node.class); |
| 130 |
> |
|
| 131 |
> |
/** |
| 132 |
> |
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package. |
| 133 |
> |
* Replace with a simple call to Unsafe.getUnsafe when integrating |
| 134 |
> |
* into a jdk. |
| 135 |
> |
* |
| 136 |
> |
* @return a sun.misc.Unsafe |
| 137 |
> |
*/ |
| 138 |
> |
private static sun.misc.Unsafe getUnsafe() { |
| 139 |
> |
try { |
| 140 |
> |
return sun.misc.Unsafe.getUnsafe(); |
| 141 |
> |
} catch (SecurityException se) { |
| 142 |
> |
try { |
| 143 |
> |
return java.security.AccessController.doPrivileged |
| 144 |
> |
(new java.security |
| 145 |
> |
.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
| 146 |
> |
public sun.misc.Unsafe run() throws Exception { |
| 147 |
> |
java.lang.reflect.Field f = sun.misc |
| 148 |
> |
.Unsafe.class.getDeclaredField("theUnsafe"); |
| 149 |
> |
f.setAccessible(true); |
| 150 |
> |
return (sun.misc.Unsafe) f.get(null); |
| 151 |
> |
}}); |
| 152 |
> |
} catch (java.security.PrivilegedActionException e) { |
| 153 |
> |
throw new RuntimeException("Could not initialize intrinsics", |
| 154 |
> |
e.getCause()); |
| 155 |
> |
} |
| 156 |
> |
} |
| 157 |
|
} |
| 158 |
|
|
| 159 |
|
private static final long serialVersionUID = -3375979862319811754L; |
| 870 |
|
|
| 871 |
|
private static final sun.misc.Unsafe UNSAFE = getUnsafe(); |
| 872 |
|
private static final long headOffset = |
| 873 |
< |
objectFieldOffset("head", LinkedTransferQueue.class); |
| 873 |
> |
objectFieldOffset(UNSAFE, "head", LinkedTransferQueue.class); |
| 874 |
|
private static final long tailOffset = |
| 875 |
< |
objectFieldOffset("tail", LinkedTransferQueue.class); |
| 875 |
> |
objectFieldOffset(UNSAFE, "tail", LinkedTransferQueue.class); |
| 876 |
|
private static final long cleanMeOffset = |
| 877 |
< |
objectFieldOffset("cleanMe", LinkedTransferQueue.class); |
| 877 |
> |
objectFieldOffset(UNSAFE, "cleanMe", LinkedTransferQueue.class); |
| 878 |
> |
|
| 879 |
|
|
| 880 |
< |
private static long objectFieldOffset(String field, Class<?> klazz) { |
| 880 |
> |
static long objectFieldOffset(sun.misc.Unsafe UNSAFE, |
| 881 |
> |
String field, Class<?> klazz) { |
| 882 |
|
try { |
| 883 |
|
return UNSAFE.objectFieldOffset(klazz.getDeclaredField(field)); |
| 884 |
|
} catch (NoSuchFieldException e) { |
