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/* |
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* Copyright (c) 2001, 2005, Oracle and/or its affiliates. All rights reserved. |
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
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* |
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* This code is free software; you can redistribute it and/or modify it |
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* under the terms of the GNU General Public License version 2 only, as |
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* published by the Free Software Foundation. |
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* |
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* This code is distributed in the hope that it will be useful, but WITHOUT |
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
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* version 2 for more details (a copy is included in the LICENSE file that |
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* accompanied this code). |
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* |
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* You should have received a copy of the GNU General Public License version |
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* 2 along with this work; if not, write to the Free Software Foundation, |
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
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* |
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
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* or visit www.oracle.com if you need additional information or have any |
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* questions. |
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*/ |
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|
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/* |
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* @test |
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* @bug 4421469 6282555 |
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* @summary Hashtable's toString method should detect self-referential |
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* hash tables rather than throwing a StackOverflowException. |
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* @author Josh Bloch, Martin Buchholz |
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*/ |
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|
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import java.util.HashMap; |
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import java.util.Hashtable; |
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import java.util.LinkedHashMap; |
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import java.util.Map; |
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import java.util.concurrent.ConcurrentHashMap; |
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|
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public class SelfRef { |
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public static void main(String[] args) { |
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testMap(new Hashtable<Object,Object>()); |
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testMap(new HashMap<Object,Object>()); |
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testMap(new LinkedHashMap<Object,Object>()); |
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testMap(new ConcurrentHashMap<Object,Object>()); |
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} |
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|
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private static void testMap(Map<Object,Object> m) { |
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if (! (m.toString().equals("{}"))) |
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throw new Error(); |
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m.put("Harvey", m); |
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if (! (m.toString().equals("{Harvey=(this Map)}"))) |
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throw new Error(); |
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m.clear(); |
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m.put(m, "Harvey"); |
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if (! (m.toString().equals("{(this Map)=Harvey}"))) |
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throw new Error(); |
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m.clear(); |
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m.hashCode(); |
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} |
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} |
