--- jsr166/src/jsr166y/ThreadLocalRandom.java	2009/07/20 21:54:51	1.4
+++ jsr166/src/jsr166y/ThreadLocalRandom.java	2009/08/19 17:52:50	1.13
@@ -5,28 +5,32 @@
  */
 
 package jsr166y;
-import java.util.*;
+
+import java.util.Random;
 
 /**
- * A random number generator with the same properties as class {@link
- * Random} but isolated to the current Thread.  Like the global
- * generator used by the {@link java.lang.Math} class, a
- * ThreadLocalRandom is initialized with an internally generated seed
- * that may not otherwise be modified. When applicable, use of
- * ThreadLocalRandom rather than shared Random objects in concurrent
- * programs will typically encounter much less overhead and
- * contention.  ThreadLocalRandoms are particularly appropriate when
- * multiple tasks (for example, each a {@link ForkJoinTask}), use
- * random numbers in parallel in thread pools.
+ * A random number generator isolated to the current thread.  Like the
+ * global {@link java.util.Random} generator used by the {@link
+ * java.lang.Math} class, a {@code ThreadLocalRandom} is initialized
+ * with an internally generated seed that may not otherwise be
+ * modified. When applicable, use of {@code ThreadLocalRandom} rather
+ * than shared {@code Random} objects in concurrent programs will
+ * typically encounter much less overhead and contention.  Use of
+ * {@code ThreadLocalRandom} is particularly appropriate when multiple
+ * tasks (for example, each a {@link ForkJoinTask}) use random numbers
+ * in parallel in thread pools.
  *
  * <p>Usages of this class should typically be of the form:
  * {@code ThreadLocalRandom.current().nextX(...)} (where
  * {@code X} is {@code Int}, {@code Long}, etc).
  * When all usages are of this form, it is never possible to
- * accidently share ThreadLocalRandoms across multiple threads.
+ * accidently share a {@code ThreadLocalRandom} across multiple threads.
  *
  * <p>This class also provides additional commonly used bounded random
  * generation methods.
+ *
+ * @since 1.7
+ * @author Doug Lea
  */
 public class ThreadLocalRandom extends Random {
     // same constants as Random, but must be redeclared because private
@@ -35,7 +39,7 @@ public class ThreadLocalRandom extends R
     private final static long mask = (1L << 48) - 1;
 
     /**
-     * The random seed. We can't use super.seed
+     * The random seed. We can't use super.seed.
      */
     private long rnd;
 
@@ -73,16 +77,18 @@ public class ThreadLocalRandom extends R
     }
 
     /**
-     * Returns the current Thread's ThreadLocalRandom
-     * @return the current Thread's ThreadLocalRandom
+     * Returns the current thread's {@code ThreadLocalRandom}.
+     *
+     * @return the current thread's {@code ThreadLocalRandom}
      */
     public static ThreadLocalRandom current() {
         return localRandom.get();
     }
 
     /**
-     * Throws UnsupportedOperationException. Setting seeds in this
-     * generator is unsupported.
+     * Throws {@code UnsupportedOperationException}.  Setting seeds in
+     * this generator is not supported.
+     *
      * @throws UnsupportedOperationException always
      */
     public void setSeed(long seed) {
@@ -93,12 +99,14 @@ public class ThreadLocalRandom extends R
     }
 
     protected int next(int bits) {
-        return (int)((rnd = (rnd * multiplier + addend) & mask) >>> (48-bits));
+        rnd = (rnd * multiplier + addend) & mask;
+        return (int) (rnd >>> (48-bits));
     }
 
     /**
      * Returns a pseudorandom, uniformly distributed value between the
      * given least value (inclusive) and bound (exclusive).
+     *
      * @param least the least value returned
      * @param bound the upper bound (exclusive)
      * @throws IllegalArgumentException if least greater than or equal
@@ -113,7 +121,8 @@ public class ThreadLocalRandom extends R
 
     /**
      * Returns a pseudorandom, uniformly distributed value
-     * between 0 (inclusive) and the specified value (exclusive)
+     * between 0 (inclusive) and the specified value (exclusive).
+     *
      * @param n the bound on the random number to be returned.  Must be
      *        positive.
      * @return the next value
@@ -131,17 +140,18 @@ public class ThreadLocalRandom extends R
         while (n >= Integer.MAX_VALUE) {
             int bits = next(2);
             long half = n >>> 1;
-            long nextn = ((bits & 2) == 0)? half : n - half;
+            long nextn = ((bits & 2) == 0) ? half : n - half;
             if ((bits & 1) == 0)
                 offset += n - nextn;
             n = nextn;
         }
-        return offset + nextInt((int)n);
+        return offset + nextInt((int) n);
     }
 
     /**
      * Returns a pseudorandom, uniformly distributed value between the
      * given least value (inclusive) and bound (exclusive).
+     *
      * @param least the least value returned
      * @param bound the upper bound (exclusive)
      * @return the next value
@@ -156,7 +166,8 @@ public class ThreadLocalRandom extends R
 
     /**
      * Returns a pseudorandom, uniformly distributed {@code double} value
-     * between 0 (inclusive) and the specified value (exclusive)
+     * between 0 (inclusive) and the specified value (exclusive).
+     *
      * @param n the bound on the random number to be returned.  Must be
      *        positive.
      * @return the next value
@@ -171,6 +182,7 @@ public class ThreadLocalRandom extends R
     /**
      * Returns a pseudorandom, uniformly distributed value between the
      * given least value (inclusive) and bound (exclusive).
+     *
      * @param least the least value returned
      * @param bound the upper bound (exclusive)
      * @return the next value
@@ -183,4 +195,5 @@ public class ThreadLocalRandom extends R
         return nextDouble() * (bound - least) + least;
     }
 
+    private static final long serialVersionUID = -5851777807851030925L;
 }