| /* |
| * Copyright (c) 2012, Oracle and/or its affiliates. All rights reserved. |
| * 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. |
| */ |
| |
| /* |
| * @test |
| * @bug 7121314 |
| * @summary AbstractCollection.toArray(T[]) doesn't return the given array |
| * in concurrent modification. |
| * @author Ulf Zibis, David Holmes |
| */ |
| |
| import java.util.AbstractCollection; |
| import java.util.Arrays; |
| import java.util.Iterator; |
| |
| public class ToArrayTest { |
| |
| static class TestCollection<E> extends AbstractCollection<E> { |
| private final E[] elements; |
| private int[] sizes; |
| private int nextSize; |
| |
| public TestCollection(E[] elements) { |
| this.elements = elements; |
| setSizeSequence(new int[] { elements.length }); |
| } |
| |
| /* |
| * Sets the values that size() will return on each use. The next |
| * call to size will return sizes[0], then sizes[1] etc. This allows us |
| * to emulate a concurrent change to the contents of the collection |
| * without having to perform concurrent changes. If sizes[n+1] contains |
| * a larger value, the collection will appear to have shrunk when |
| * iterated; if a smaller value then the collection will appear to have |
| * grown when iterated. |
| */ |
| void setSizeSequence(int... sizes) { |
| this.sizes = sizes; |
| nextSize = 0; |
| } |
| |
| /* can change collection's size after each invocation */ |
| @Override |
| public int size() { |
| return sizes[nextSize == sizes.length - 1 ? nextSize : nextSize++]; |
| } |
| |
| @Override |
| public Iterator<E> iterator() { |
| return new Iterator<E>() { |
| int pos = 0; |
| |
| public boolean hasNext() { |
| return pos < sizes[nextSize]; |
| } |
| public E next() { |
| return elements[pos++]; |
| } |
| public void remove() { |
| throw new UnsupportedOperationException( |
| "Not supported yet."); |
| } |
| }; |
| } |
| } |
| |
| static final Object[] OBJECTS = { new Object(), new Object(), new Object() }; |
| static final TestCollection<?> CANDIDATE = new TestCollection<Object>(OBJECTS); |
| static final int CAP = OBJECTS.length; // capacity of the CANDIDATE |
| static final int LAST = CAP - 1; // last possible array index |
| Object[] a; |
| Object[] res; |
| |
| int last() { |
| return a.length - 1; |
| } |
| |
| protected void test() throws Throwable { |
| // Check array type conversion |
| res = new TestCollection<>(new Object[] { "1", "2" }).toArray(new String[0]); |
| check(res instanceof String[]); |
| check(res.length == 2); |
| check(res[1] == "2"); |
| |
| // Check incompatible type of target array |
| try { |
| res = CANDIDATE.toArray(new String[CAP]); |
| check(false); |
| } catch (Throwable t) { |
| check(t instanceof ArrayStoreException); |
| } |
| |
| // Check more elements than a.length |
| a = new Object[CAP - 1]; // appears too small |
| res = CANDIDATE.toArray(a); |
| check(res != a); |
| check(res[LAST] != null); |
| |
| // Check equal elements as a.length |
| a = new Object[CAP]; // appears to match |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] != null); |
| |
| // Check equal elements as a.length |
| a = new Object[CAP + 1]; // appears too big |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] == null); |
| |
| // Check less elements than expected, but more than a.length |
| a = new Object[CAP - 2]; // appears too small |
| CANDIDATE.setSizeSequence(CAP, CAP - 1); |
| res = CANDIDATE.toArray(a); |
| check(res != a); |
| check(res.length == CAP - 1); |
| check(res[LAST - 1] != null); |
| |
| // Check less elements than expected, but equal as a.length |
| a = Arrays.copyOf(OBJECTS, CAP); // appears to match |
| CANDIDATE.setSizeSequence(CAP, CAP - 1); |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] == null); |
| |
| // Check more elements than expected and more than a.length |
| a = new Object[CAP - 1]; // appears to match |
| CANDIDATE.setSizeSequence(CAP - 1, CAP); |
| res = CANDIDATE.toArray(a); |
| check(res != a); |
| check(res[LAST] != null); |
| |
| // Check more elements than expected, but equal as a.length |
| a = new Object[CAP - 1]; // appears to match |
| CANDIDATE.setSizeSequence(CAP - 2, CAP - 1); |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] != null); |
| |
| // Check more elements than expected, but less than a.length |
| a = Arrays.copyOf(OBJECTS, CAP); // appears to match |
| CANDIDATE.setSizeSequence(CAP - 2, CAP - 1); |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] == null); |
| |
| test_7121314(); |
| } |
| |
| /* |
| * Major target of this testcase, bug 7121314. |
| */ |
| protected void test_7121314() throws Throwable { |
| // Check equal elements as a.length, but less than expected |
| a = new Object[CAP - 1]; // appears too small |
| CANDIDATE.setSizeSequence(CAP, CAP - 1); |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] != null); |
| |
| // Check less elements than a.length and less than expected |
| a = Arrays.copyOf(OBJECTS, CAP - 1); // appears too small |
| CANDIDATE.setSizeSequence(CAP, CAP - 2); |
| res = CANDIDATE.toArray(a); |
| check(res == a); |
| check(res[last()] == null); |
| |
| } |
| |
| public static void main(String[] args) throws Throwable { |
| ToArrayTest testcase = new ToArrayTest(); |
| try { |
| testcase.test(); |
| } catch (Throwable t) { |
| unexpected(t); |
| } |
| |
| System.out.printf("%nPassed = %d, failed = %d%n%n", passed, failed); |
| if (failed > 0) throw new Exception("Some tests failed"); |
| } |
| |
| //--------------------- Infrastructure --------------------------- |
| static volatile int passed = 0, failed = 0; |
| static void pass() { passed++; } |
| static void fail() { failed++; Thread.dumpStack(); } |
| static void fail(String msg) { System.out.println(msg); fail(); } |
| static void unexpected(Throwable t) { failed++; t.printStackTrace(); } |
| static void check(boolean cond) { if (cond) pass(); else fail(); } |
| static void equal(Object x, Object y) { |
| if (x == null ? y == null : x.equals(y)) pass(); |
| else {System.out.println(x + " not equal to " + y); fail(); } |
| } |
| } |