--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/math/RandomSeed.java Fri Mar 06 16:00:58 2015 -0800
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2015, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+import java.util.Random;
+import java.util.SplittableRandom;
+
+public class RandomSeed {
+ private long seed = 0L;
+ private Random rnd = null;
+ private SplittableRandom srnd = null;
+
+ public RandomSeed(boolean isSplittableRandom) {
+ init(isSplittableRandom);
+ }
+
+ private void init(boolean isSplittableRandom) {
+ // obtain seed from environment if supplied
+ boolean isSeedProvided = false;
+ try {
+ // note that Long.valueOf(null) also throws a NumberFormatException
+ // so if the property is undefined this will still work correctly
+ seed = Long.valueOf(System.getProperty("seed"));
+ isSeedProvided = true;
+ } catch (NumberFormatException e) {
+ // do nothing: isSeedProvided is already false
+ }
+
+ // if no seed from environment, create a fresh one
+ Random tmpRnd = null;
+ if (!isSeedProvided) {
+ tmpRnd = new Random();
+ seed = tmpRnd.nextLong();
+ }
+
+ // create the PRNG
+ if (isSplittableRandom) {
+ srnd = new SplittableRandom(seed);
+ } else {
+ rnd = tmpRnd != null ? tmpRnd : new Random();
+ rnd.setSeed(seed);
+ }
+ }
+
+ public Random getRandom() {
+ if (rnd == null) {
+ throw new IllegalStateException("Variable of type Random not initialized");
+ }
+ return rnd;
+ }
+
+ public SplittableRandom getSplittableRandom() {
+ if (srnd == null) {
+ throw new IllegalStateException("Variable of type SplittableRandom not initialized");
+ }
+ return srnd;
+ }
+
+ public long getSeed() {
+ return seed;
+ }
+}