--- /dev/null 2015-01-04 16:41:02.701408369 +0100 +++ new/test/java/util/Hashtable/DeserializedLength.java 2015-01-04 18:46:53.662073317 +0100 @@ -0,0 +1,97 @@ +/* + * 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.ByteArrayInputStream; +import java.io.ByteArrayOutputStream; +import java.io.ObjectInputStream; +import java.io.ObjectOutputStream; +import java.lang.reflect.Field; +import java.util.Hashtable; + +/** + * @test + * @bug 8068427 + * @summary Hashtable deserialization reconstitutes table with wrong capacity + */ +public class DeserializedLength { + + static boolean testDeserializedLength(int elements) throws Exception { + // construct Hashtable + float loadFactor = 0.75f; + Hashtable ht1 = new Hashtable<>( + (int) (elements / loadFactor) + 1, + loadFactor + ); + for (int i = 0; i < elements; i++) { + ht1.put(i, i); + } + + // serialize it to byte[] array + byte[] bytes; + try (ByteArrayOutputStream baos = new ByteArrayOutputStream(); + ObjectOutputStream oos = new ObjectOutputStream(baos)) { + oos.writeObject(ht1); + oos.flush(); + bytes = baos.toByteArray(); + } + + // de-serialize it from byte[] array + Hashtable ht2; + try (ByteArrayInputStream bais = new ByteArrayInputStream(bytes); + ObjectInputStream ois = new ObjectInputStream(bais)) { + ht2 = (Hashtable) ois.readObject(); + } + + // compare lengths of internal tables + Object[] table1 = (Object[]) hashtableTableField.get(ht1); + Object[] table2 = (Object[]) hashtableTableField.get(ht2); + + System.out.println("Serialized Hashtable of size=" + ht1.size() + + " has internal table.length=" + table1.length + + " de-serialized table.length=" + table2.length); + + return table2.length >= table1.length; + } + + 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; + ok &= testDeserializedLength(10); + ok &= testDeserializedLength(50); + ok &= testDeserializedLength(500); + ok &= testDeserializedLength(5000); + if (!ok) { + throw new AssertionError("Test failed."); + } + } +}