| /* |
| * Copyright (c) 2014, 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. |
| */ |
| |
| import java.io.*; |
| import java.lang.reflect.Field; |
| import java.util.Hashtable; |
| |
| /** |
| * @test |
| * @bug 8068427 |
| * @summary Hashtable deserialization reconstitutes table with wrong capacity |
| * @modules java.base/java.util:open |
| */ |
| public class DeserializedLength { |
| |
| static boolean testDeserializedLength(int elements, float loadFactor) throws Exception { |
| |
| // construct Hashtable with minimal initial capacity and given loadFactor |
| Hashtable<Integer, Integer> ht1 = new Hashtable<>(1, loadFactor); |
| |
| // add given number of unique elements |
| for (int i = 0; i < elements; i++) { |
| ht1.put(i, i); |
| } |
| |
| // serialize and deserialize into a deep clone |
| Hashtable<Integer, Integer> ht2 = serialClone(ht1); |
| |
| // compare lengths of internal tables |
| Object[] table1 = (Object[]) hashtableTableField.get(ht1); |
| Object[] table2 = (Object[]) hashtableTableField.get(ht2); |
| assert table1 != null; |
| assert table2 != null; |
| |
| int minLength = (int) (ht1.size() / loadFactor) + 1; |
| int maxLength = minLength * 2; |
| |
| boolean ok = (table2.length >= minLength && table2.length <= maxLength); |
| |
| System.out.printf( |
| "%7d %5.2f %7d %7d %7d...%7d %s\n", |
| ht1.size(), loadFactor, |
| table1.length, table2.length, |
| minLength, maxLength, |
| (ok ? "OK" : "NOT-OK") |
| ); |
| |
| return ok; |
| } |
| |
| static <T> T serialClone(T o) throws IOException, ClassNotFoundException { |
| ByteArrayOutputStream bos = new ByteArrayOutputStream(); |
| try (ObjectOutputStream oos = new ObjectOutputStream(bos)) { |
| oos.writeObject(o); |
| } |
| @SuppressWarnings("unchecked") |
| T clone = (T) new ObjectInputStream( |
| new ByteArrayInputStream(bos.toByteArray())).readObject(); |
| return clone; |
| } |
| |
| private static final Field hashtableTableField; |
| |
| static { |
| try { |
| hashtableTableField = Hashtable.class.getDeclaredField("table"); |
| hashtableTableField.setAccessible(true); |
| } catch (NoSuchFieldException e) { |
| throw new Error(e); |
| } |
| } |
| |
| public static void main(String[] args) throws Exception { |
| boolean ok = true; |
| |
| System.out.printf("Results:\n" + |
| " ser. deser.\n" + |
| " size load lentgh length valid range ok?\n" + |
| "------- ----- ------- ------- ----------------- ------\n" |
| ); |
| |
| for (int elements : new int[]{10, 50, 500, 5000}) { |
| for (float loadFactor : new float[]{0.15f, 0.5f, 0.75f, 1.0f, 2.5f}) { |
| ok &= testDeserializedLength(elements, loadFactor); |
| } |
| } |
| if (!ok) { |
| throw new AssertionError("Test failed."); |
| } |
| } |
| } |