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package jsr166y; |
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import java.util.concurrent.*; |
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< |
import java.util.concurrent.atomic.*; |
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import java.util.concurrent.atomic.AtomicReference; |
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import java.util.concurrent.locks.LockSupport; |
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/** |
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} |
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/** |
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< |
* Returns the parent of this phaser, or null if none. |
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> |
* Returns the parent of this phaser, or {@code null} if none. |
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* |
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< |
* @return the parent of this phaser, or null if none |
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> |
* @return the parent of this phaser, or {@code null} if none |
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*/ |
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public Phaser getParent() { |
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return parent; |
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* Overridable method to perform an action upon phase advance, and |
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* to control termination. This method is invoked whenever the |
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* barrier is tripped (and thus all other waiting parties are |
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< |
* dormant). If it returns true, then, rather than advance the |
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< |
* phase number, this barrier will be set to a final termination |
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< |
* state, and subsequent calls to {@code isTerminated} will |
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< |
* return true. |
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> |
* dormant). If it returns {@code true}, then, rather than advance |
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> |
* the phase number, this barrier will be set to a final |
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* termination state, and subsequent calls to {@link #isTerminated} |
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* will return true. |
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* |
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< |
* <p> The default version returns true when the number of |
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* <p> The default version returns {@code true} when the number of |
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* registered parties is zero. Normally, overrides that arrange |
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* termination for other reasons should also preserve this |
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* property. |
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return p; |
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} |
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|
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< |
// Unsafe mechanics for jsr166y 3rd party package. |
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> |
// Unsafe mechanics |
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> |
|
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> |
private static final sun.misc.Unsafe UNSAFE = getUnsafe(); |
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> |
private static final long stateOffset = |
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> |
objectFieldOffset("state", Phaser.class); |
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> |
|
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> |
private final boolean casState(long cmp, long val) { |
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> |
return UNSAFE.compareAndSwapLong(this, stateOffset, cmp, val); |
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> |
} |
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> |
|
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> |
private static long objectFieldOffset(String field, Class<?> klazz) { |
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> |
try { |
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> |
return UNSAFE.objectFieldOffset(klazz.getDeclaredField(field)); |
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> |
} catch (NoSuchFieldException e) { |
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> |
// Convert Exception to corresponding Error |
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> |
NoSuchFieldError error = new NoSuchFieldError(field); |
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> |
error.initCause(e); |
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throw error; |
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} |
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> |
} |
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> |
|
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> |
/** |
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> |
* Returns a sun.misc.Unsafe. Suitable for use in a 3rd party package. |
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> |
* Replace with a simple call to Unsafe.getUnsafe when integrating |
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> |
* into a jdk. |
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> |
* |
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> |
* @return a sun.misc.Unsafe |
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> |
*/ |
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private static sun.misc.Unsafe getUnsafe() { |
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try { |
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return sun.misc.Unsafe.getUnsafe(); |
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} catch (SecurityException se) { |
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try { |
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return java.security.AccessController.doPrivileged |
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< |
(new java.security.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
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> |
(new java.security |
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> |
.PrivilegedExceptionAction<sun.misc.Unsafe>() { |
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public sun.misc.Unsafe run() throws Exception { |
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< |
return getUnsafeByReflection(); |
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> |
java.lang.reflect.Field f = sun.misc |
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> |
.Unsafe.class.getDeclaredField("theUnsafe"); |
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> |
f.setAccessible(true); |
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return (sun.misc.Unsafe) f.get(null); |
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}}); |
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} catch (java.security.PrivilegedActionException e) { |
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throw new RuntimeException("Could not initialize intrinsics", |
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} |
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} |
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} |
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|
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private static sun.misc.Unsafe getUnsafeByReflection() |
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throws NoSuchFieldException, IllegalAccessException { |
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java.lang.reflect.Field f = |
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sun.misc.Unsafe.class.getDeclaredField("theUnsafe"); |
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f.setAccessible(true); |
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return (sun.misc.Unsafe) f.get(null); |
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} |
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|
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private static long fieldOffset(String fieldName, Class<?> klazz) { |
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try { |
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return UNSAFE.objectFieldOffset(klazz.getDeclaredField(fieldName)); |
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} catch (NoSuchFieldException e) { |
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// Convert Exception to Error |
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NoSuchFieldError error = new NoSuchFieldError(fieldName); |
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error.initCause(e); |
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throw error; |
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} |
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} |
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|
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private static final sun.misc.Unsafe UNSAFE = getUnsafe(); |
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static final long stateOffset = |
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fieldOffset("state", Phaser.class); |
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|
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final boolean casState(long cmp, long val) { |
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return UNSAFE.compareAndSwapLong(this, stateOffset, cmp, val); |
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} |
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} |
