/* * 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/ * Other contributors include Andrew Wright, Jeffrey Hayes, * Pat Fisher, Mike Judd. */ import java.util.Arrays; import java.util.concurrent.atomic.AtomicIntegerArray; import junit.framework.Test; import junit.framework.TestSuite; public class AtomicIntegerArrayTest extends JSR166TestCase { public static void main(String[] args) { main(suite(), args); } public static Test suite() { return new TestSuite(AtomicIntegerArrayTest.class); } /** * constructor creates array of given size with all elements zero */ public void testConstructor() { AtomicIntegerArray aa = new AtomicIntegerArray(SIZE); for (int i = 0; i < SIZE; i++) assertEquals(0, aa.get(i)); } /** * constructor with null array throws NPE */ public void testConstructor2NPE() { try { int[] a = null; new AtomicIntegerArray(a); shouldThrow(); } catch (NullPointerException success) {} } /** * constructor with array is of same size and has all elements */ public void testConstructor2() { int[] a = { 17, 3, -42, 99, -7 }; AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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 Exception { final AtomicIntegerArray a = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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() { AtomicIntegerArray aa = new AtomicIntegerArray(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 AtomicIntegerArray aa; int decs; Counter(AtomicIntegerArray a) { aa = a; } public void realRun() { for (;;) { boolean done = true; for (int i = 0; i < aa.length(); i++) { int v = aa.get(i); assertTrue(v >= 0); if (v != 0) { done = false; if (aa.compareAndSet(i, v, v - 1)) decs++; } } 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 AtomicIntegerArray aa = new AtomicIntegerArray(SIZE); int countdown = 10000; for (int i = 0; i < SIZE; i++) aa.set(i, countdown); Counter c1 = new Counter(aa); Counter c2 = new Counter(aa); Thread t1 = newStartedThread(c1); Thread t2 = newStartedThread(c2); t1.join(); t2.join(); assertEquals(c1.decs + c2.decs, SIZE * countdown); } /** * a deserialized serialized array holds same values */ public void testSerialization() throws Exception { AtomicIntegerArray x = new AtomicIntegerArray(SIZE); for (int i = 0; i < SIZE; i++) x.set(i, -i); AtomicIntegerArray 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() { int[] a = { 17, 3, -42, 99, -7 }; AtomicIntegerArray aa = new AtomicIntegerArray(a); assertEquals(Arrays.toString(a), aa.toString()); } }