| /* |
| * Copyright 2016 Google, Inc. 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 8148174 |
| * @summary brittle white box test of internal array management |
| * @run testng ArrayManagement |
| */ |
| |
| import java.lang.reflect.Field; |
| import java.util.AbstractList; |
| import java.util.Vector; |
| import java.util.Collections; |
| import java.util.List; |
| import java.util.SplittableRandom; |
| |
| import org.testng.annotations.Test; |
| import static org.testng.Assert.*; |
| |
| public class ArrayManagement { |
| |
| /** |
| * A Vector that exposes all protected elements, and checks class |
| * invariants. |
| */ |
| static class PublicVector<E> extends Vector<E> { |
| public PublicVector() { super(); } |
| public PublicVector(int capacity) { super(capacity); } |
| public PublicVector(int capacity, int capacityIncrement) { |
| super(capacity, capacityIncrement); |
| } |
| public Object[] elementData() { return elementData; } |
| public int modCount() { return modCount; } |
| public int capacityIncrement() { return capacityIncrement; } |
| public int capacity() { return elementData.length; } |
| |
| public void ensureCapacity(int minCapacity) { |
| int oldCapacity = capacity(); |
| int oldModCount = modCount(); |
| super.ensureCapacity(minCapacity); |
| assertTrue(capacity() >= minCapacity); |
| if (minCapacity <= oldCapacity) |
| assertEquals(capacity(), oldCapacity); |
| if (minCapacity > 0) |
| assertEquals(modCount(), oldModCount + 1); |
| } |
| } |
| |
| static final int DEFAULT_CAPACITY = 10; |
| static final SplittableRandom rnd = new SplittableRandom(); |
| |
| static int newCapacity(int oldCapacity) { |
| return 2 * oldCapacity; |
| } |
| |
| static List<Object> singletonList() { |
| return Collections.singletonList(Boolean.TRUE); |
| } |
| |
| /** Opportunistically randomly test various add operations. */ |
| static void addOneElement(PublicVector<Object> list) { |
| int size = list.size(); |
| int modCount = list.modCount(); |
| switch (rnd.nextInt(4)) { |
| case 0: assertTrue(list.add(Boolean.TRUE)); break; |
| case 1: list.add(size, Boolean.TRUE); break; |
| case 2: assertTrue(list.addAll(singletonList())); break; |
| case 3: assertTrue(list.addAll(size, singletonList())); break; |
| default: throw new AssertionError(); |
| } |
| assertEquals(list.modCount(), modCount + 1); |
| assertEquals(list.size(), size + 1); |
| } |
| |
| @Test public void defaultCapacity() { |
| PublicVector<Object> list = new PublicVector<>(); |
| assertEquals(new PublicVector<Object>().capacity(), DEFAULT_CAPACITY); |
| for (int i = 0; i < DEFAULT_CAPACITY; i++) { |
| addOneElement(list); |
| assertEquals(list.capacity(), DEFAULT_CAPACITY); |
| } |
| addOneElement(list); |
| assertEquals(list.capacity(), newCapacity(DEFAULT_CAPACITY)); |
| } |
| |
| @Test public void defaultCapacityEnsureCapacity() { |
| PublicVector<Object> list = new PublicVector<>(); |
| for (int i = 0; i <= DEFAULT_CAPACITY; i++) { |
| list.ensureCapacity(i); // no-op! |
| assertEquals(list.capacity(), DEFAULT_CAPACITY); |
| } |
| for (int i = 0; i < DEFAULT_CAPACITY; i++) { |
| addOneElement(list); |
| assertEquals(list.capacity(), DEFAULT_CAPACITY); |
| } |
| addOneElement(list); |
| assertEquals(list.capacity(), newCapacity(DEFAULT_CAPACITY)); |
| { |
| int capacity = list.capacity(); |
| list.ensureCapacity(capacity + 1); |
| assertEquals(list.capacity(), newCapacity(capacity)); |
| } |
| { |
| int capacity = list.capacity(); |
| list.ensureCapacity(3 * capacity); |
| assertEquals(list.capacity(), 3 * capacity); |
| } |
| } |
| |
| @Test public void ensureCapacityBeyondDefaultCapacity() { |
| PublicVector<Object> list = new PublicVector<>(); |
| list.ensureCapacity(DEFAULT_CAPACITY + 1); |
| assertEquals(list.capacity(), newCapacity(DEFAULT_CAPACITY)); |
| } |
| |
| @Test public void explicitZeroCapacity() { |
| PublicVector<Object> list = new PublicVector<>(0); |
| assertEquals(list.capacity(), 0); |
| addOneElement(list); |
| assertEquals(list.capacity(), 1); |
| addOneElement(list); |
| assertEquals(list.capacity(), 2); |
| addOneElement(list); |
| assertEquals(list.capacity(), 4); |
| addOneElement(list); |
| assertEquals(list.capacity(), 4); |
| addOneElement(list); |
| assertEquals(list.capacity(), 8); |
| addOneElement(list); |
| assertEquals(list.capacity(), 8); |
| addOneElement(list); |
| assertEquals(list.capacity(), 8); |
| list.clear(); |
| assertEquals(list.capacity(), 8); |
| } |
| |
| @Test public void explicitZeroCapacityWithCapacityIncrement() { |
| PublicVector<Object> list = new PublicVector<>(0, 2); |
| assertEquals(list.capacity(), 0); |
| addOneElement(list); |
| assertEquals(list.capacity(), 2); |
| addOneElement(list); |
| assertEquals(list.capacity(), 2); |
| addOneElement(list); |
| assertEquals(list.capacity(), 4); |
| addOneElement(list); |
| assertEquals(list.capacity(), 4); |
| addOneElement(list); |
| assertEquals(list.capacity(), 6); |
| addOneElement(list); |
| assertEquals(list.capacity(), 6); |
| addOneElement(list); |
| assertEquals(list.capacity(), 8); |
| list.clear(); |
| assertEquals(list.capacity(), 8); |
| } |
| |
| @Test public void explicitLargeCapacity() { |
| int n = DEFAULT_CAPACITY * 3; |
| PublicVector<Object> list = new PublicVector<>(n); |
| assertEquals(list.capacity(), n); |
| list.ensureCapacity(0); |
| list.ensureCapacity(n); |
| for (int i = 0; i < n; i++) addOneElement(list); |
| assertEquals(list.capacity(), n); |
| |
| addOneElement(list); |
| assertEquals(list.capacity(), newCapacity(n)); |
| } |
| |
| @Test public void explicitLargeCapacityWithCapacityIncrement() { |
| int n = DEFAULT_CAPACITY * 3; |
| PublicVector<Object> list = new PublicVector<>(n, 2); |
| assertEquals(list.capacity(), n); |
| list.ensureCapacity(0); |
| list.ensureCapacity(n); |
| for (int i = 0; i < n; i++) addOneElement(list); |
| assertEquals(list.capacity(), n); |
| |
| addOneElement(list); |
| assertEquals(list.capacity(), n + 2); |
| } |
| |
| @Test public void emptyArraysAreNotShared() { |
| assertNotSame(new PublicVector<Object>(0).elementData(), |
| new PublicVector<Object>(0).elementData()); |
| } |
| |
| @Test public void negativeCapacity() { |
| for (int capacity : new int[] { -1, Integer.MIN_VALUE }) { |
| try { |
| new Vector<Object>(capacity); |
| fail("should throw"); |
| } catch (IllegalArgumentException success) {} |
| } |
| } |
| } |