| /* |
| * Copyright (c) 2001, 2005, 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. |
| */ |
| |
| /** |
| * @test |
| * @bug 4421469 6282555 |
| * @summary Hashtable's toString method should detect self-referential |
| * hash tables rather than throwing a StackOverflowException. |
| * @author Josh Bloch, Martin Buchholz |
| */ |
| |
| import java.util.*; |
| import java.util.concurrent.*; |
| |
| public class SelfRef { |
| public static void main(String[] args) { |
| testMap(new Hashtable<Object,Object>()); |
| testMap(new HashMap<Object,Object>()); |
| testMap(new LinkedHashMap<Object,Object>()); |
| testMap(new ConcurrentHashMap<Object,Object>()); |
| } |
| |
| private static void testMap(Map<Object,Object> m) { |
| if (! (m.toString().equals("{}"))) |
| throw new Error(); |
| m.put("Harvey", m); |
| if (! (m.toString().equals("{Harvey=(this Map)}"))) |
| throw new Error(); |
| m.clear(); |
| m.put(m, "Harvey"); |
| if (! (m.toString().equals("{(this Map)=Harvey}"))) |
| throw new Error(); |
| m.clear(); |
| m.hashCode(); |
| } |
| } |