util/ArrayList/ArrayManagement.java

59     static Object[] elementData(ArrayList<?> list) {
61             return (Object[]) ELEMENT_DATA.get(list);
67     static int modCount(ArrayList<?> list) {
69             return MODCOUNT.getInt(list);
75     static int capacity(ArrayList<?> list) {
76         return elementData(list).length;
83     static void ensureCapacity(ArrayList<Object> list, int capacity) {
84         int oldCapacity = capacity(list);
85         int oldModCount = modCount(list);
86         list.ensureCapacity(capacity);
87         assertTrue(capacity(list) >= capacity || capacity(list) == 0);
88         assertEquals(modCount(list),
89                      (capacity(list) == oldCapacity)
99     static void addOneElement(ArrayList<Object> list) {
100         int size = list.size();
101         int modCount = modCount(list);
103         case 0: assertTrue(list.add(Boolean.TRUE)); break;
104         case 1: list.add(size, Boolean.TRUE); break;
105         case 2: assertTrue(list.addAll(singletonList())); break;
106         case 3: assertTrue(list.addAll(size, singletonList())); break;
109         assertEquals(modCount(list), modCount + 1);
110         assertEquals(list.size(), size + 1);
114         ArrayList<Object> list = new ArrayList<>();
117             addOneElement(list);
118             assertEquals(capacity(list), DEFAULT_CAPACITY);
120         addOneElement(list);
121         assertEquals(capacity(list), newCapacity(DEFAULT_CAPACITY));
125         ArrayList<Object> list = new ArrayList<>();
127             ensureCapacity(list, i);     // no-op!
128             assertEquals(capacity(list), 0);
131             addOneElement(list);
132             assertEquals(capacity(list), DEFAULT_CAPACITY);
134         addOneElement(list);
135         assertEquals(capacity(list), newCapacity(DEFAULT_CAPACITY));
137             int capacity = capacity(list);
138             ensureCapacity(list, capacity + 1);
139             assertEquals(capacity(list), newCapacity(capacity));
142             int capacity = capacity(list);
143             ensureCapacity(list, 3 * capacity);
144             assertEquals(capacity(list), 3 * capacity);
149         ArrayList<Object> list = new ArrayList<>();
150         list.ensureCapacity(DEFAULT_CAPACITY + 1);
151         assertEquals(capacity(list), DEFAULT_CAPACITY + 1);
153             addOneElement(list);
154             assertEquals(capacity(list), DEFAULT_CAPACITY + 1);
156         addOneElement(list);
157         assertEquals(capacity(list), newCapacity(DEFAULT_CAPACITY + 1));
161         ArrayList<Object> list = new ArrayList<>(0);
162         assertEquals(capacity(list), 0);
163         addOneElement(list);
164         assertEquals(capacity(list), 1);
165         addOneElement(list);
166         assertEquals(capacity(list), 2);
167         addOneElement(list);
168         assertEquals(capacity(list), 3);
169         addOneElement(list);
170         assertEquals(capacity(list), 4);
171         addOneElement(list);
172         assertEquals(capacity(list), 6);
173         addOneElement(list);
174         assertEquals(capacity(list), 6);
175         addOneElement(list);
176         assertEquals(capacity(list), 9);
177         list.clear();
178         assertEquals(capacity(list), 9);
183         ArrayList<Object> list = new ArrayList<>(n);
184         assertEquals(capacity(list), n);
185         ensureCapacity(list, 0);
186         ensureCapacity(list, n);
187         for (int i = 0; i < n; i++) addOneElement(list);
188         assertEquals(capacity(list), n);
190         addOneElement(list);
191         assertEquals(capacity(list), newCapacity(n));