/*
* 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.AtomicReferenceFieldUpdater;
import junit.framework.Test;
import junit.framework.TestSuite;
public class AtomicReferenceFieldUpdaterTest extends JSR166TestCase {
volatile Integer x = null;
protected volatile Integer protectedField;
private volatile Integer privateField;
Object z;
Integer w;
volatile int i;
public static void main(String[] args) {
main(suite(), args);
}
public static Test suite() {
return new TestSuite(AtomicReferenceFieldUpdaterTest.class);
}
// for testing subclass access
static class AtomicReferenceFieldUpdaterTestSubclass extends AtomicReferenceFieldUpdaterTest {
public void checkPrivateAccess() {
try {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest,Integer> a =
AtomicReferenceFieldUpdater.newUpdater
(AtomicReferenceFieldUpdaterTest.class, Integer.class, "privateField");
shouldThrow();
} catch (RuntimeException success) {
assertNotNull(success.getCause());
}
}
public void checkCompareAndSetProtectedSub() {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest,Integer> a =
AtomicReferenceFieldUpdater.newUpdater
(AtomicReferenceFieldUpdaterTest.class, Integer.class, "protectedField");
this.protectedField = one;
assertTrue(a.compareAndSet(this, one, two));
assertTrue(a.compareAndSet(this, two, m4));
assertSame(m4, a.get(this));
assertFalse(a.compareAndSet(this, m5, seven));
assertFalse(seven == a.get(this));
assertTrue(a.compareAndSet(this, m4, seven));
assertSame(seven, a.get(this));
}
}
static class UnrelatedClass {
public void checkPackageAccess(AtomicReferenceFieldUpdaterTest obj) {
obj.x = one;
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest,Integer> a =
AtomicReferenceFieldUpdater.newUpdater
(AtomicReferenceFieldUpdaterTest.class, Integer.class, "x");
assertSame(one, a.get(obj));
assertTrue(a.compareAndSet(obj, one, two));
assertSame(two, a.get(obj));
}
public void checkPrivateAccess(AtomicReferenceFieldUpdaterTest obj) {
try {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest,Integer> a =
AtomicReferenceFieldUpdater.newUpdater
(AtomicReferenceFieldUpdaterTest.class, Integer.class, "privateField");
throw new AssertionError("should throw");
} catch (RuntimeException success) {
assertNotNull(success.getCause());
}
}
}
static AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> updaterFor(String fieldName) {
return AtomicReferenceFieldUpdater.newUpdater
(AtomicReferenceFieldUpdaterTest.class, Integer.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 ClassCastException
*/
public void testConstructor2() {
try {
updaterFor("z");
shouldThrow();
} catch (ClassCastException success) {}
}
/**
* Constructor with non-volatile field throws IllegalArgumentException
*/
public void testConstructor3() {
try {
updaterFor("w");
shouldThrow();
} catch (IllegalArgumentException success) {}
}
/**
* Constructor with non-reference field throws ClassCastException
*/
public void testConstructor4() {
try {
updaterFor("i");
shouldThrow();
} catch (ClassCastException success) {}
}
/**
* construction using private field from subclass throws RuntimeException
*/
public void testPrivateFieldInSubclass() {
AtomicReferenceFieldUpdaterTestSubclass s =
new AtomicReferenceFieldUpdaterTestSubclass();
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() {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
a = updaterFor("x");
x = one;
assertSame(one, a.get(this));
a.set(this, two);
assertSame(two, a.get(this));
a.set(this, m3);
assertSame(m3, a.get(this));
}
/**
* get returns the last value lazySet by same thread
*/
public void testGetLazySet() {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
a = updaterFor("x");
x = one;
assertSame(one, a.get(this));
a.lazySet(this, two);
assertSame(two, a.get(this));
a.lazySet(this, m3);
assertSame(m3, a.get(this));
}
/**
* compareAndSet succeeds in changing value if equal to expected else fails
*/
public void testCompareAndSet() {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
a = updaterFor("x");
x = one;
assertTrue(a.compareAndSet(this, one, two));
assertTrue(a.compareAndSet(this, two, m4));
assertSame(m4, a.get(this));
assertFalse(a.compareAndSet(this, m5, seven));
assertFalse(seven == a.get(this));
assertTrue(a.compareAndSet(this, m4, seven));
assertSame(seven, a.get(this));
}
/**
* compareAndSet in one thread enables another waiting for value
* to succeed
*/
public void testCompareAndSetInMultipleThreads() throws Exception {
x = one;
final AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
a = updaterFor("x");
Thread t = new Thread(new CheckedRunnable() {
public void realRun() {
while (!a.compareAndSet(AtomicReferenceFieldUpdaterTest.this, two, three))
Thread.yield();
}});
t.start();
assertTrue(a.compareAndSet(this, one, two));
t.join(LONG_DELAY_MS);
assertFalse(t.isAlive());
assertSame(three, a.get(this));
}
/**
* repeated weakCompareAndSet succeeds in changing value when equal
* to expected
*/
public void testWeakCompareAndSet() {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
a = updaterFor("x");
x = one;
do {} while (!a.weakCompareAndSet(this, one, two));
do {} while (!a.weakCompareAndSet(this, two, m4));
assertSame(m4, a.get(this));
do {} while (!a.weakCompareAndSet(this, m4, seven));
assertSame(seven, a.get(this));
}
/**
* getAndSet returns previous value and sets to given value
*/
public void testGetAndSet() {
AtomicReferenceFieldUpdater<AtomicReferenceFieldUpdaterTest, Integer> a;
a = updaterFor("x");
x = one;
assertSame(one, a.getAndSet(this, zero));
assertSame(zero, a.getAndSet(this, m10));
assertSame(m10, a.getAndSet(this, 1));
}
}