/*

 * 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.concurrent.atomic.AtomicIntegerFieldUpdater;

import junit.framework.Test;

import junit.framework.TestSuite;

public class AtomicIntegerFieldUpdaterTest extends JSR166TestCase {

    volatile int x = 0;

    protected volatile int protectedField;

    private volatile int privateField;

    int w;

    float z;

    public static void main(String[] args) {

        main(suite(), args);

    }

    public static Test suite() {

        return new TestSuite(AtomicIntegerFieldUpdaterTest.class);

    }

    // for testing subclass access

    static class AtomicIntegerFieldUpdaterTestSubclass extends AtomicIntegerFieldUpdaterTest {

        public void checkPrivateAccess() {

            try {

                AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a =

                    AtomicIntegerFieldUpdater.newUpdater

                    (AtomicIntegerFieldUpdaterTest.class, "privateField");

                shouldThrow();

            } catch (RuntimeException success) {

                assertNotNull(success.getCause());

            }

        }

        public void checkCompareAndSetProtectedSub() {

            AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a =

                AtomicIntegerFieldUpdater.newUpdater

                (AtomicIntegerFieldUpdaterTest.class, "protectedField");

            this.protectedField = 1;

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

            assertTrue(a.compareAndSet(this, 2, -4));

            assertEquals(-4, a.get(this));

            assertFalse(a.compareAndSet(this, -5, 7));

            assertEquals(-4, a.get(this));

            assertTrue(a.compareAndSet(this, -4, 7));

            assertEquals(7, a.get(this));

        }

    }

    static class UnrelatedClass {

        public void checkPackageAccess(AtomicIntegerFieldUpdaterTest obj) {

            obj.x = 72;

            AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a =

                AtomicIntegerFieldUpdater.newUpdater

                (AtomicIntegerFieldUpdaterTest.class, "x");

            assertEquals(72, a.get(obj));

            assertTrue(a.compareAndSet(obj, 72, 73));

            assertEquals(73, a.get(obj));

        }

        public void checkPrivateAccess(AtomicIntegerFieldUpdaterTest obj) {

            try {

                AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a =

                    AtomicIntegerFieldUpdater.newUpdater

                    (AtomicIntegerFieldUpdaterTest.class, "privateField");

                throw new AssertionError("should throw");

            } catch (RuntimeException success) {

                assertNotNull(success.getCause());

            }

        }

    }

    AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> updaterFor(String fieldName) {

        return AtomicIntegerFieldUpdater.newUpdater

            (AtomicIntegerFieldUpdaterTest.class, fieldName);

    }

    /**

     * Construction with non-existent field throws RuntimeException

     */

    public void testConstructor() {

        try {

            updaterFor("y");

            shouldThrow();

        } catch (RuntimeException success) {

            assertNotNull(success.getCause());

        }

    }

    /**

     * construction with field not of given type throws IllegalArgumentException

     */

    public void testConstructor2() {

        try {

            updaterFor("z");

            shouldThrow();

        } catch (IllegalArgumentException success) {}

    }

    /**

     * construction with non-volatile field throws IllegalArgumentException

     */

    public void testConstructor3() {

        try {

            updaterFor("w");

            shouldThrow();

        } catch (IllegalArgumentException success) {}

    }

    /**

     * construction using private field from subclass throws RuntimeException

     */

    public void testPrivateFieldInSubclass() {

        AtomicIntegerFieldUpdaterTestSubclass s =

            new AtomicIntegerFieldUpdaterTestSubclass();

        s.checkPrivateAccess();

    }

    /**

     * construction from unrelated class; package access is allowed,

     * private access is not

     */

    public void testUnrelatedClassAccess() {

        new UnrelatedClass().checkPackageAccess(this);

        new UnrelatedClass().checkPrivateAccess(this);

    }

    /**

     * get returns the last value set or assigned

     */

    public void testGetSet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(1, a.get(this));

        a.set(this, 2);

        assertEquals(2, a.get(this));

        a.set(this, -3);

        assertEquals(-3, a.get(this));

    }

    /**

     * get returns the last value lazySet by same thread

     */

    public void testGetLazySet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(1, a.get(this));

        a.lazySet(this, 2);

        assertEquals(2, a.get(this));

        a.lazySet(this, -3);

        assertEquals(-3, a.get(this));

    }

    /**

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

     */

    public void testCompareAndSet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

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

        assertTrue(a.compareAndSet(this, 2, -4));

        assertEquals(-4, a.get(this));

        assertFalse(a.compareAndSet(this, -5, 7));

        assertEquals(-4, a.get(this));

        assertTrue(a.compareAndSet(this, -4, 7));

        assertEquals(7, a.get(this));

    }

    /**

     * compareAndSet succeeds in changing protected field value if

     * equal to expected else fails

     */

    public void testCompareAndSetProtected() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("protectedField");

        protectedField = 1;

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

        assertTrue(a.compareAndSet(this, 2, -4));

        assertEquals(-4, a.get(this));

        assertFalse(a.compareAndSet(this, -5, 7));

        assertEquals(-4, a.get(this));

        assertTrue(a.compareAndSet(this, -4, 7));

        assertEquals(7, a.get(this));

    }

    /**

     * compareAndSet succeeds in changing protected field value if

     * equal to expected else fails

     */

    public void testCompareAndSetProtectedInSubclass() {

        AtomicIntegerFieldUpdaterTestSubclass s =

            new AtomicIntegerFieldUpdaterTestSubclass();

        s.checkCompareAndSetProtectedSub();

    }

    /**

     * compareAndSet in one thread enables another waiting for value

     * to succeed

     */

    public void testCompareAndSetInMultipleThreads() throws Exception {

        x = 1;

        final AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        Thread t = new Thread(new CheckedRunnable() {

            public void realRun() {

                while (!a.compareAndSet(AtomicIntegerFieldUpdaterTest.this, 2, 3))

                    Thread.yield();

            }});

        t.start();

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

        t.join(LONG_DELAY_MS);

        assertFalse(t.isAlive());

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

    }

    /**

     * repeated weakCompareAndSet succeeds in changing value when equal

     * to expected

     */

    public void testWeakCompareAndSet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        do {} while (!a.weakCompareAndSet(this, 1, 2));

        do {} while (!a.weakCompareAndSet(this, 2, -4));

        assertEquals(-4, a.get(this));

        do {} while (!a.weakCompareAndSet(this, -4, 7));

        assertEquals(7, a.get(this));

    }

    /**

     * getAndSet returns previous value and sets to given value

     */

    public void testGetAndSet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(1, a.getAndSet(this, 0));

        assertEquals(0, a.getAndSet(this, -10));

        assertEquals(-10, a.getAndSet(this, 1));

    }

    /**

     * getAndAdd returns previous value and adds given value

     */

    public void testGetAndAdd() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(1, a.getAndAdd(this, 2));

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

        assertEquals(3, a.getAndAdd(this, -4));

        assertEquals(-1, a.get(this));

    }

    /**

     * getAndDecrement returns previous value and decrements

     */

    public void testGetAndDecrement() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(1, a.getAndDecrement(this));

        assertEquals(0, a.getAndDecrement(this));

        assertEquals(-1, a.getAndDecrement(this));

    }

    /**

     * getAndIncrement returns previous value and increments

     */

    public void testGetAndIncrement() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(1, a.getAndIncrement(this));

        assertEquals(2, a.get(this));

        a.set(this, -2);

        assertEquals(-2, a.getAndIncrement(this));

        assertEquals(-1, a.getAndIncrement(this));

        assertEquals(0, a.getAndIncrement(this));

        assertEquals(1, a.get(this));

    }

    /**

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

     */

    public void testAddAndGet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(3, a.addAndGet(this, 2));

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

        assertEquals(-1, a.addAndGet(this, -4));

        assertEquals(-1, a.get(this));

    }

    /**

     * decrementAndGet decrements and returns current value

     */

    public void testDecrementAndGet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(0, a.decrementAndGet(this));

        assertEquals(-1, a.decrementAndGet(this));

        assertEquals(-2, a.decrementAndGet(this));

        assertEquals(-2, a.get(this));

    }

    /**

     * incrementAndGet increments and returns current value

     */

    public void testIncrementAndGet() {

        AtomicIntegerFieldUpdater<AtomicIntegerFieldUpdaterTest> a;

        a = updaterFor("x");

        x = 1;

        assertEquals(2, a.incrementAndGet(this));

        assertEquals(2, a.get(this));

        a.set(this, -2);

        assertEquals(-1, a.incrementAndGet(this));

        assertEquals(0, a.incrementAndGet(this));

        assertEquals(1, a.incrementAndGet(this));

        assertEquals(1, a.get(this));

    }

}