--- jsr166/src/main/java/util/Random.java	2005/11/06 07:47:51	1.12
+++ jsr166/src/main/java/util/Random.java	2007/01/07 07:38:27	1.18
@@ -1,13 +1,14 @@
 /*
  * %W% %E%
  *
- * Copyright 2005 Sun Microsystems, Inc. All rights reserved.
+ * Copyright 2007 Sun Microsystems, Inc. All rights reserved.
  * SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
  */
 
 package java.util;
 import java.io.*;
 import java.util.concurrent.atomic.AtomicLong;
+import sun.misc.Unsafe;
 
 /**
  * An instance of this class is used to generate a stream of
@@ -47,7 +48,7 @@ class Random implements java.io.Serializ
      *
      * @serial
      */
-    private AtomicLong seed;
+    private final AtomicLong seed;
 
     private final static long multiplier = 0x5DEECE66DL;
     private final static long addend = 0xBL;
@@ -135,7 +136,7 @@ class Random implements java.io.Serializ
         do {
 	    oldseed = seed.get();
 	    nextseed = (oldseed * multiplier + addend) & mask;
-        } while (!seed.compareAndSet(oldseed, nextseed));
+        } while (!seed.weakCompareAndSet(oldseed, nextseed));
         return (int)(nextseed >>> (48 - bits));
     }
 
@@ -492,7 +493,7 @@ class Random implements java.io.Serializ
         if (seedVal < 0)
           throw new java.io.StreamCorruptedException(
                               "Random: invalid seed");
-        seed = new AtomicLong(seedVal);
+        resetSeed(seedVal);
         nextNextGaussian = fields.get("nextNextGaussian", 0.0);
         haveNextNextGaussian = fields.get("haveNextNextGaussian", false);
     }
@@ -515,4 +516,16 @@ class Random implements java.io.Serializ
         s.writeFields();
     }
 
+    // Support for resetting seed while deserializing
+    private static final Unsafe unsafe = Unsafe.getUnsafe();
+    private static final long seedOffset;
+    static {
+        try {
+            seedOffset = unsafe.objectFieldOffset
+                (Random.class.getDeclaredField("seed"));
+	} catch (Exception ex) { throw new Error(ex); }
+    }
+    private void resetSeed(long seedVal) {
+        unsafe.putObjectVolatile(this, seedOffset, new AtomicLong(seedVal));
+    }
 }