/*

 * 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

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 */

/*

 * 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/

 * Other contributors include Andrew Wright, Jeffrey Hayes,

 * Pat Fisher, Mike Judd.

 */

import java.util.Arrays;

import java.util.concurrent.atomic.AtomicLongArray;

import junit.framework.Test;

import junit.framework.TestSuite;

public class AtomicLongArrayTest extends JSR166TestCase {

    public static void main(String[] args) {

        main(suite(), args);

    }

    public static Test suite() {

        return new TestSuite(AtomicLongArrayTest.class);

    }

    /**

     * constructor creates array of given size with all elements zero

     */

    public void testConstructor() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++)

            assertEquals(0, aa.get(i));

    }

    /**

     * constructor with null array throws NPE

     */

    public void testConstructor2NPE() {

        try {

            long[] a = null;

            new AtomicLongArray(a);

            shouldThrow();

        } catch (NullPointerException success) {}

    }

    /**

     * constructor with array is of same size and has all elements

     */

    public void testConstructor2() {

        long[] a = { 17L, 3L, -42L, 99L, -7L };

        AtomicLongArray aa = new AtomicLongArray(a);

        assertEquals(a.length, aa.length());

        for (int i = 0; i < a.length; i++)

            assertEquals(a[i], aa.get(i));

    }

    /**

     * get and set for out of bound indices throw IndexOutOfBoundsException

     */

    public void testIndexing() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int index : new int[] { -1, SIZE }) {

            try {

                aa.get(index);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

            try {

                aa.set(index, 1);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

            try {

                aa.lazySet(index, 1);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

            try {

                aa.compareAndSet(index, 1, 2);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

            try {

                aa.weakCompareAndSet(index, 1, 2);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

            try {

                aa.getAndAdd(index, 1);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

            try {

                aa.addAndGet(index, 1);

                shouldThrow();

            } catch (IndexOutOfBoundsException success) {}

        }

    }

    /**

     * get returns the last value set at index

     */

    public void testGetSet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(1, aa.get(i));

            aa.set(i, 2);

            assertEquals(2, aa.get(i));

            aa.set(i, -3);

            assertEquals(-3, aa.get(i));

        }

    }

    /**

     * get returns the last value lazySet at index by same thread

     */

    public void testGetLazySet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.lazySet(i, 1);

            assertEquals(1, aa.get(i));

            aa.lazySet(i, 2);

            assertEquals(2, aa.get(i));

            aa.lazySet(i, -3);

            assertEquals(-3, aa.get(i));

        }

    }

    /**

     * compareAndSet succeeds in changing value if equal to expected else fails

     */

    public void testCompareAndSet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertTrue(aa.compareAndSet(i, 1, 2));

            assertTrue(aa.compareAndSet(i, 2, -4));

            assertEquals(-4, aa.get(i));

            assertFalse(aa.compareAndSet(i, -5, 7));

            assertEquals(-4, aa.get(i));

            assertTrue(aa.compareAndSet(i, -4, 7));

            assertEquals(7, aa.get(i));

        }

    }

    /**

     * compareAndSet in one thread enables another waiting for value

     * to succeed

     */

    public void testCompareAndSetInMultipleThreads() throws InterruptedException {

        final AtomicLongArray a = new AtomicLongArray(1);

        a.set(0, 1);

        Thread t = new Thread(new CheckedRunnable() {

            public void realRun() {

                while (!a.compareAndSet(0, 2, 3))

                    Thread.yield();

            }});

        t.start();

        assertTrue(a.compareAndSet(0, 1, 2));

        t.join(LONG_DELAY_MS);

        assertFalse(t.isAlive());

        assertEquals(3, a.get(0));

    }

    /**

     * repeated weakCompareAndSet succeeds in changing value when equal

     * to expected

     */

    public void testWeakCompareAndSet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            do {} while (!aa.weakCompareAndSet(i, 1, 2));

            do {} while (!aa.weakCompareAndSet(i, 2, -4));

            assertEquals(-4, aa.get(i));

            do {} while (!aa.weakCompareAndSet(i, -4, 7));

            assertEquals(7, aa.get(i));

        }

    }

    /**

     * getAndSet returns previous value and sets to given value at given index

     */

    public void testGetAndSet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(1, aa.getAndSet(i, 0));

            assertEquals(0, aa.getAndSet(i, -10));

            assertEquals(-10, aa.getAndSet(i, 1));

        }

    }

    /**

     * getAndAdd returns previous value and adds given value

     */

    public void testGetAndAdd() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(1, aa.getAndAdd(i, 2));

            assertEquals(3, aa.get(i));

            assertEquals(3, aa.getAndAdd(i, -4));

            assertEquals(-1, aa.get(i));

        }

    }

    /**

     * getAndDecrement returns previous value and decrements

     */

    public void testGetAndDecrement() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(1, aa.getAndDecrement(i));

            assertEquals(0, aa.getAndDecrement(i));

            assertEquals(-1, aa.getAndDecrement(i));

        }

    }

    /**

     * getAndIncrement returns previous value and increments

     */

    public void testGetAndIncrement() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(1, aa.getAndIncrement(i));

            assertEquals(2, aa.get(i));

            aa.set(i, -2);

            assertEquals(-2, aa.getAndIncrement(i));

            assertEquals(-1, aa.getAndIncrement(i));

            assertEquals(0, aa.getAndIncrement(i));

            assertEquals(1, aa.get(i));

        }

    }

    /**

     * addAndGet adds given value to current, and returns current value

     */

    public void testAddAndGet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(3, aa.addAndGet(i, 2));

            assertEquals(3, aa.get(i));

            assertEquals(-1, aa.addAndGet(i, -4));

            assertEquals(-1, aa.get(i));

        }

    }

    /**

     * decrementAndGet decrements and returns current value

     */

    public void testDecrementAndGet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(0, aa.decrementAndGet(i));

            assertEquals(-1, aa.decrementAndGet(i));

            assertEquals(-2, aa.decrementAndGet(i));

            assertEquals(-2, aa.get(i));

        }

    }

    /**

     * incrementAndGet increments and returns current value

     */

    public void testIncrementAndGet() {

        AtomicLongArray aa = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++) {

            aa.set(i, 1);

            assertEquals(2, aa.incrementAndGet(i));

            assertEquals(2, aa.get(i));

            aa.set(i, -2);

            assertEquals(-1, aa.incrementAndGet(i));

            assertEquals(0, aa.incrementAndGet(i));

            assertEquals(1, aa.incrementAndGet(i));

            assertEquals(1, aa.get(i));

        }

    }

    class Counter extends CheckedRunnable {

        final AtomicLongArray aa;

        Counter(AtomicLongArray a) { aa = a; }

        public void realRun() {

            for (;;) {

                boolean done = true;

                for (int i = 0; i < aa.length(); i++) {

                    long v = aa.get(i);

                    assertTrue(v >= 0);

                    if (v != 0) {

                        done = false;

                        if (aa.compareAndSet(i, v, v - 1))

                    }

                }

                if (done)

                    break;

            }

        }

    }

    /**

     * Multiple threads using same array of counters successfully

     * update a number of times equal to total count

     */

    public void testCountingInMultipleThreads() throws InterruptedException {

        final AtomicLongArray aa = new AtomicLongArray(SIZE);

        long countdown = 10000;

        for (int i = 0; i < SIZE; i++)

            aa.set(i, countdown);

        Counter c1 = new Counter(aa);

        Counter c2 = new Counter(aa);

        t1.join();

        t2.join();

    }

    /**

     * a deserialized serialized array holds same values

     */

    public void testSerialization() throws Exception {

        AtomicLongArray x = new AtomicLongArray(SIZE);

        for (int i = 0; i < SIZE; i++)

            x.set(i, -i);

        AtomicLongArray y = serialClone(x);

        assertNotSame(x, y);

        assertEquals(x.length(), y.length());

        for (int i = 0; i < SIZE; i++) {

            assertEquals(x.get(i), y.get(i));

        }

    }

    /**

     * toString returns current value.

     */

    public void testToString() {

        long[] a = { 17, 3, -42, 99, -7 };

        AtomicLongArray aa = new AtomicLongArray(a);

        assertEquals(Arrays.toString(a), aa.toString());

    }

}