--- jsr166/src/jsr166y/ForkJoinTask.java	2013/01/01 15:10:39	1.98
+++ jsr166/src/jsr166y/ForkJoinTask.java	2016/06/30 14:17:04	1.104
@@ -71,7 +71,7 @@ import java.lang.reflect.Constructor;
  * encountering the exception; minimally only the latter.
  *
  * <p>It is possible to define and use ForkJoinTasks that may block,
- * but doing do requires three further considerations: (1) Completion
+ * but doing so requires three further considerations: (1) Completion
  * of few if any <em>other</em> tasks should be dependent on a task
  * that blocks on external synchronization or I/O. Event-style async
  * tasks that are never joined (for example, those subclassing {@link
@@ -395,11 +395,13 @@ public abstract class ForkJoinTask<V> im
         final Throwable ex;
         ExceptionNode next;
         final long thrower;  // use id not ref to avoid weak cycles
+        final int hashCode;  // store task hashCode before weak ref disappears
         ExceptionNode(ForkJoinTask<?> task, Throwable ex, ExceptionNode next) {
             super(task, exceptionTableRefQueue);
             this.ex = ex;
             this.next = next;
             this.thrower = Thread.currentThread().getId();
+            this.hashCode = System.identityHashCode(task);
         }
     }
 
@@ -468,7 +470,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Removes exception node and clears status
+     * Removes exception node and clears status.
      */
     private void clearExceptionalCompletion() {
         int h = System.identityHashCode(this);
@@ -561,9 +563,9 @@ public abstract class ForkJoinTask<V> im
     private static void expungeStaleExceptions() {
         for (Object x; (x = exceptionTableRefQueue.poll()) != null;) {
             if (x instanceof ExceptionNode) {
-                ForkJoinTask<?> key = ((ExceptionNode)x).get();
+                int hashCode = ((ExceptionNode)x).hashCode;
                 ExceptionNode[] t = exceptionTable;
-                int i = System.identityHashCode(key) & (t.length - 1);
+                int i = hashCode & (t.length - 1);
                 ExceptionNode e = t[i];
                 ExceptionNode pred = null;
                 while (e != null) {
@@ -1065,10 +1067,10 @@ public abstract class ForkJoinTask<V> im
 
     /**
      * Possibly executes tasks until the pool hosting the current task
-     * {@link ForkJoinPool#isQuiescent is quiescent}. This method may
-     * be of use in designs in which many tasks are forked, but none
-     * are explicitly joined, instead executing them until all are
-     * processed.
+     * {@linkplain ForkJoinPool#isQuiescent is quiescent}.  This
+     * method may be of use in designs in which many tasks are forked,
+     * but none are explicitly joined, instead executing them until
+     * all are processed.
      */
     public static void helpQuiesce() {
         Thread t;
@@ -1326,7 +1328,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Adaptor for Runnables. This implements RunnableFuture
+     * Adapter for Runnables. This implements RunnableFuture
      * to be compliant with AbstractExecutorService constraints
      * when used in ForkJoinPool.
      */
@@ -1347,7 +1349,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Adaptor for Runnables without results
+     * Adapter for Runnables without results
      */
     static final class AdaptedRunnableAction extends ForkJoinTask<Void>
         implements RunnableFuture<Void> {
@@ -1364,7 +1366,7 @@ public abstract class ForkJoinTask<V> im
     }
 
     /**
-     * Adaptor for Callables
+     * Adapter for Callables
      */
     static final class AdaptedCallable<T> extends ForkJoinTask<T>
         implements RunnableFuture<T> {
@@ -1485,22 +1487,23 @@ public abstract class ForkJoinTask<V> im
     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());
         }
     }
-
 }