0N/A/*
2362N/A * Copyright (c) 2002, Oracle and/or its affiliates. All rights reserved.
0N/A * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
0N/A *
0N/A * This code is free software; you can redistribute it and/or modify it
0N/A * under the terms of the GNU General Public License version 2 only, as
0N/A * published by the Free Software Foundation.
0N/A *
0N/A * This code is distributed in the hope that it will be useful, but WITHOUT
0N/A * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
0N/A * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
0N/A * version 2 for more details (a copy is included in the LICENSE file that
0N/A * accompanied this code).
0N/A *
0N/A * You should have received a copy of the GNU General Public License version
0N/A * 2 along with this work; if not, write to the Free Software Foundation,
0N/A * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
0N/A *
2362N/A * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
2362N/A * or visit www.oracle.com if you need additional information or have any
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0N/A */
0N/A
0N/A/*
0N/A * @test
0N/A * @bug 4684279
0N/A * @summary Empty utility collections should be singletons
0N/A * @author Josh Bloch
0N/A */
0N/A
0N/Aimport java.util.*;
0N/Aimport java.io.*;
0N/A
0N/Apublic class EmptyCollectionSerialization {
0N/A private static Object patheticDeepCopy(Object o) throws Exception {
0N/A // Serialize
0N/A ByteArrayOutputStream bos = new ByteArrayOutputStream();
0N/A ObjectOutputStream oos = new ObjectOutputStream(bos);
0N/A oos.writeObject(o);
0N/A byte[] serializedForm = bos.toByteArray();
0N/A
0N/A // Deserialize
0N/A InputStream is = new ByteArrayInputStream(serializedForm);
0N/A ObjectInputStream ois = new ObjectInputStream(is);
0N/A return ois.readObject();
0N/A }
0N/A
0N/A private static boolean isSingleton(Object o) throws Exception {
0N/A return patheticDeepCopy(o) == o;
0N/A }
0N/A
0N/A public static void main(String[] args) throws Exception {
0N/A if (!isSingleton(Collections.EMPTY_SET))
0N/A throw new Exception("EMPTY_SET");
0N/A if (!isSingleton(Collections.EMPTY_LIST))
0N/A throw new Exception("EMPTY_LIST");
0N/A if (!isSingleton(Collections.EMPTY_MAP))
0N/A throw new Exception("EMPTY_MAP");
0N/A }
0N/A}