--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/test/java/util/concurrent/tck/LongAccumulatorTest.java	Fri Jan 29 11:44:19 2016 -0800
@@ -0,0 +1,183 @@
+/*
+ * 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.
+ */
+
+/*
+ * This file is available under and governed by the GNU General Public
+ * License version 2 only, as published by the Free Software Foundation.
+ * However, the following notice accompanied the original version of this
+ * file:
+ *
+ * Written by Doug Lea with assistance from members of JCP JSR-166
+ * Expert Group and released to the public domain, as explained at
+ * http://creativecommons.org/publicdomain/zero/1.0/
+ */
+
+import java.util.concurrent.Executors;
+import java.util.concurrent.ExecutorService;
+import java.util.concurrent.Phaser;
+import java.util.concurrent.atomic.LongAccumulator;
+
+import junit.framework.Test;
+import junit.framework.TestSuite;
+
+public class LongAccumulatorTest extends JSR166TestCase {
+    public static void main(String[] args) {
+        main(suite(), args);
+    }
+    public static Test suite() {
+        return new TestSuite(LongAccumulatorTest.class);
+    }
+
+    /**
+     * default constructed initializes to zero
+     */
+    public void testConstructor() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        assertEquals(0, ai.get());
+    }
+
+    /**
+     * accumulate accumulates given value to current, and get returns current value
+     */
+    public void testAccumulateAndGet() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        ai.accumulate(2);
+        assertEquals(2, ai.get());
+        ai.accumulate(-4);
+        assertEquals(2, ai.get());
+        ai.accumulate(4);
+        assertEquals(4, ai.get());
+    }
+
+    /**
+     * reset() causes subsequent get() to return zero
+     */
+    public void testReset() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        ai.accumulate(2);
+        assertEquals(2, ai.get());
+        ai.reset();
+        assertEquals(0, ai.get());
+    }
+
+    /**
+     * getThenReset() returns current value; subsequent get() returns zero
+     */
+    public void testGetThenReset() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        ai.accumulate(2);
+        assertEquals(2, ai.get());
+        assertEquals(2, ai.getThenReset());
+        assertEquals(0, ai.get());
+    }
+
+    /**
+     * toString returns current value.
+     */
+    public void testToString() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        assertEquals("0", ai.toString());
+        ai.accumulate(1);
+        assertEquals(Long.toString(1), ai.toString());
+    }
+
+    /**
+     * intValue returns current value.
+     */
+    public void testIntValue() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        assertEquals(0, ai.intValue());
+        ai.accumulate(1);
+        assertEquals(1, ai.intValue());
+    }
+
+    /**
+     * longValue returns current value.
+     */
+    public void testLongValue() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        assertEquals(0, ai.longValue());
+        ai.accumulate(1);
+        assertEquals(1, ai.longValue());
+    }
+
+    /**
+     * floatValue returns current value.
+     */
+    public void testFloatValue() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        assertEquals(0.0f, ai.floatValue());
+        ai.accumulate(1);
+        assertEquals(1.0f, ai.floatValue());
+    }
+
+    /**
+     * doubleValue returns current value.
+     */
+    public void testDoubleValue() {
+        LongAccumulator ai = new LongAccumulator(Long::max, 0L);
+        assertEquals(0.0, ai.doubleValue());
+        ai.accumulate(1);
+        assertEquals(1.0, ai.doubleValue());
+    }
+
+    /**
+     * accumulates by multiple threads produce correct result
+     */
+    public void testAccumulateAndGetMT() {
+        final int incs = 1000000;
+        final int nthreads = 4;
+        final ExecutorService pool = Executors.newCachedThreadPool();
+        LongAccumulator a = new LongAccumulator(Long::max, 0L);
+        Phaser phaser = new Phaser(nthreads + 1);
+        for (int i = 0; i < nthreads; ++i)
+            pool.execute(new AccTask(a, phaser, incs));
+        phaser.arriveAndAwaitAdvance();
+        phaser.arriveAndAwaitAdvance();
+        long expected = incs - 1;
+        long result = a.get();
+        assertEquals(expected, result);
+        pool.shutdown();
+    }
+
+    static final class AccTask implements Runnable {
+        final LongAccumulator acc;
+        final Phaser phaser;
+        final int incs;
+        volatile long result;
+        AccTask(LongAccumulator acc, Phaser phaser, int incs) {
+            this.acc = acc;
+            this.phaser = phaser;
+            this.incs = incs;
+        }
+
+        public void run() {
+            phaser.arriveAndAwaitAdvance();
+            LongAccumulator a = acc;
+            for (int i = 0; i < incs; ++i)
+                a.accumulate(i);
+            result = a.get();
+            phaser.arrive();
+        }
+    }
+
+}