jdk/src/share/classes/java/lang/StrictMath.java
changeset 5781 11a42d91eb56
parent 5506 202f599c92aa
child 7517 7303bc0e78d6
--- a/jdk/src/share/classes/java/lang/StrictMath.java	Thu Jun 10 15:54:25 2010 -0700
+++ b/jdk/src/share/classes/java/lang/StrictMath.java	Thu Jun 10 15:55:26 2010 -0700
@@ -667,9 +667,9 @@
 
     private static Random randomNumberGenerator;
 
-    private static synchronized void initRNG() {
-        if (randomNumberGenerator == null)
-            randomNumberGenerator = new Random();
+    private static synchronized Random initRNG() {
+        Random rnd = randomNumberGenerator;
+        return (rnd == null) ? (randomNumberGenerator = new Random()) : rnd;
     }
 
     /**
@@ -680,9 +680,11 @@
      *
      * <p>When this method is first called, it creates a single new
      * pseudorandom-number generator, exactly as if by the expression
-     * <blockquote>{@code new java.util.Random}</blockquote> This
-     * new pseudorandom-number generator is used thereafter for all
-     * calls to this method and is used nowhere else.
+     *
+     * <blockquote>{@code new java.util.Random()}</blockquote>
+     *
+     * This new pseudorandom-number generator is used thereafter for
+     * all calls to this method and is used nowhere else.
      *
      * <p>This method is properly synchronized to allow correct use by
      * more than one thread. However, if many threads need to generate
@@ -691,11 +693,12 @@
      *
      * @return  a pseudorandom {@code double} greater than or equal
      * to {@code 0.0} and less than {@code 1.0}.
-     * @see     java.util.Random#nextDouble()
+     * @see Random#nextDouble()
      */
     public static double random() {
-        if (randomNumberGenerator == null) initRNG();
-        return randomNumberGenerator.nextDouble();
+        Random rnd = randomNumberGenerator;
+        if (rnd == null) rnd = initRNG();
+        return rnd.nextDouble();
     }
 
     /**