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/* |
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* %W% %E% |
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* Copyright (c) 1997, 2007, 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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* Copyright 2005 Sun Microsystems, Inc. All rights reserved. |
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* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
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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. Sun designates this |
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* particular file as subject to the "Classpath" exception as provided |
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* by Sun in the LICENSE file that accompanied this code. |
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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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package java.util; |
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* constructor, as per the recommendation in the <tt>Map</tt> interface |
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* specification. |
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* |
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< |
* <p>The documentation for each non-abstract methods in this class describes its |
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* <p>The documentation for each non-abstract method in this class describes its |
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* implementation in detail. Each of these methods may be overridden if the |
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* map being implemented admits a more efficient implementation. |
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* |
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* <p>This class is a member of the |
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* <a href="{@docRoot}/../guide/collections/index.html"> |
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* <a href="{@docRoot}/../technotes/guides/collections/index.html"> |
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* Java Collections Framework</a>. |
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* |
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* @param <K> the type of keys maintained by this map |
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* |
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* @author Josh Bloch |
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* @author Neal Gafter |
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* @version %I%, %G% |
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* @see Map |
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* @see Collection |
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* @since 1.2 |
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* <p>This implementation returns <tt>entrySet().size()</tt>. |
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*/ |
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public int size() { |
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return entrySet().size(); |
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return entrySet().size(); |
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} |
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|
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/** |
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* <p>This implementation returns <tt>size() == 0</tt>. |
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*/ |
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public boolean isEmpty() { |
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return size() == 0; |
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return size() == 0; |
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} |
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|
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/** |
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* finding such an entry, <tt>false</tt> is returned. Note that this |
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* implementation requires linear time in the size of the map. |
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* |
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* @throws NullPointerException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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*/ |
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public boolean containsValue(Object value) { |
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Iterator<Entry<K,V>> i = entrySet().iterator(); |
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if (value==null) { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getValue()==null) |
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return true; |
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} |
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} else { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (value.equals(e.getValue())) |
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return true; |
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} |
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} |
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return false; |
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Iterator<Entry<K,V>> i = entrySet().iterator(); |
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if (value==null) { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getValue()==null) |
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return true; |
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} |
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} else { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (value.equals(e.getValue())) |
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return true; |
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} |
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} |
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return false; |
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} |
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|
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/** |
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* implementation requires linear time in the size of the map; many |
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* implementations will override this method. |
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* |
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* @throws NullPointerException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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*/ |
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public boolean containsKey(Object key) { |
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Iterator<Map.Entry<K,V>> i = entrySet().iterator(); |
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if (key==null) { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getKey()==null) |
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return true; |
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} |
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} else { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (key.equals(e.getKey())) |
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return true; |
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} |
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} |
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return false; |
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Iterator<Map.Entry<K,V>> i = entrySet().iterator(); |
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if (key==null) { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getKey()==null) |
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return true; |
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} |
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} else { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (key.equals(e.getKey())) |
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return true; |
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} |
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} |
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return false; |
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} |
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|
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/** |
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* implementation requires linear time in the size of the map; many |
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* implementations will override this method. |
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* |
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– |
* @throws NullPointerException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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*/ |
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public V get(Object key) { |
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Iterator<Entry<K,V>> i = entrySet().iterator(); |
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if (key==null) { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getKey()==null) |
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return e.getValue(); |
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} |
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} else { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (key.equals(e.getKey())) |
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return e.getValue(); |
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} |
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} |
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return null; |
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Iterator<Entry<K,V>> i = entrySet().iterator(); |
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if (key==null) { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getKey()==null) |
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return e.getValue(); |
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} |
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} else { |
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while (i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (key.equals(e.getKey())) |
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return e.getValue(); |
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} |
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} |
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return null; |
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} |
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|
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|
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* <tt>UnsupportedOperationException</tt>. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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* @throws IllegalArgumentException {@inheritDoc} |
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*/ |
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public V put(K key, V value) { |
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throw new UnsupportedOperationException(); |
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throw new UnsupportedOperationException(); |
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} |
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|
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/** |
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* contains a mapping for the specified key. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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* @throws NullPointerException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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+ |
* @throws NullPointerException {@inheritDoc} |
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*/ |
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public V remove(Object key) { |
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Iterator<Entry<K,V>> i = entrySet().iterator(); |
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Entry<K,V> correctEntry = null; |
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if (key==null) { |
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while (correctEntry==null && i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getKey()==null) |
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correctEntry = e; |
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} |
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} else { |
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while (correctEntry==null && i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (key.equals(e.getKey())) |
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correctEntry = e; |
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} |
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} |
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|
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V oldValue = null; |
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< |
if (correctEntry !=null) { |
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oldValue = correctEntry.getValue(); |
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< |
i.remove(); |
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} |
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return oldValue; |
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> |
Iterator<Entry<K,V>> i = entrySet().iterator(); |
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Entry<K,V> correctEntry = null; |
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if (key==null) { |
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> |
while (correctEntry==null && i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (e.getKey()==null) |
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correctEntry = e; |
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} |
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} else { |
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while (correctEntry==null && i.hasNext()) { |
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Entry<K,V> e = i.next(); |
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if (key.equals(e.getKey())) |
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correctEntry = e; |
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} |
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} |
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|
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V oldValue = null; |
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if (correctEntry !=null) { |
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oldValue = correctEntry.getValue(); |
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i.remove(); |
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} |
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return oldValue; |
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} |
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|
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|
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* the <tt>put</tt> operation and the specified map is nonempty. |
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* |
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* @throws UnsupportedOperationException {@inheritDoc} |
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– |
* @throws NullPointerException {@inheritDoc} |
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* @throws ClassCastException {@inheritDoc} |
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+ |
* @throws NullPointerException {@inheritDoc} |
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* @throws IllegalArgumentException {@inheritDoc} |
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*/ |
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public void putAll(Map<? extends K, ? extends V> m) { |
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< |
Iterator<? extends Entry<? extends K, ? extends V>> i = m.entrySet().iterator(); |
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< |
while (i.hasNext()) { |
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< |
Entry<? extends K, ? extends V> e = i.next(); |
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put(e.getKey(), e.getValue()); |
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< |
} |
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> |
for (Map.Entry<? extends K, ? extends V> e : m.entrySet()) |
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put(e.getKey(), e.getValue()); |
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} |
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|
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/** |
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* @throws UnsupportedOperationException {@inheritDoc} |
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*/ |
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public void clear() { |
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< |
entrySet().clear(); |
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> |
entrySet().clear(); |
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} |
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|
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|
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* method will not all return the same set. |
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*/ |
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public Set<K> keySet() { |
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< |
if (keySet == null) { |
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< |
keySet = new AbstractSet<K>() { |
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< |
public Iterator<K> iterator() { |
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< |
return new Iterator<K>() { |
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< |
private Iterator<Entry<K,V>> i = entrySet().iterator(); |
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< |
|
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< |
public boolean hasNext() { |
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< |
return i.hasNext(); |
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< |
} |
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< |
|
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< |
public K next() { |
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< |
return i.next().getKey(); |
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< |
} |
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< |
|
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< |
public void remove() { |
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< |
i.remove(); |
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< |
} |
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> |
if (keySet == null) { |
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> |
keySet = new AbstractSet<K>() { |
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> |
public Iterator<K> iterator() { |
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> |
return new Iterator<K>() { |
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> |
private Iterator<Entry<K,V>> i = entrySet().iterator(); |
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> |
|
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> |
public boolean hasNext() { |
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> |
return i.hasNext(); |
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> |
} |
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> |
|
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> |
public K next() { |
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> |
return i.next().getKey(); |
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} |
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> |
|
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> |
public void remove() { |
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i.remove(); |
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> |
} |
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}; |
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< |
} |
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> |
} |
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> |
|
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> |
public int size() { |
| 339 |
> |
return AbstractMap.this.size(); |
| 340 |
> |
} |
| 341 |
> |
|
| 342 |
> |
public boolean isEmpty() { |
| 343 |
> |
return AbstractMap.this.isEmpty(); |
| 344 |
> |
} |
| 345 |
|
|
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< |
public int size() { |
| 347 |
< |
return AbstractMap.this.size(); |
| 348 |
< |
} |
| 349 |
< |
|
| 350 |
< |
public boolean contains(Object k) { |
| 351 |
< |
return AbstractMap.this.containsKey(k); |
| 352 |
< |
} |
| 353 |
< |
}; |
| 354 |
< |
} |
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< |
return keySet; |
| 346 |
> |
public void clear() { |
| 347 |
> |
AbstractMap.this.clear(); |
| 348 |
> |
} |
| 349 |
> |
|
| 350 |
> |
public boolean contains(Object k) { |
| 351 |
> |
return AbstractMap.this.containsKey(k); |
| 352 |
> |
} |
| 353 |
> |
}; |
| 354 |
> |
} |
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> |
return keySet; |
| 356 |
|
} |
| 357 |
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|
| 358 |
|
/** |
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* method will not all return the same collection. |
| 372 |
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*/ |
| 373 |
|
public Collection<V> values() { |
| 374 |
< |
if (values == null) { |
| 375 |
< |
values = new AbstractCollection<V>() { |
| 376 |
< |
public Iterator<V> iterator() { |
| 377 |
< |
return new Iterator<V>() { |
| 378 |
< |
private Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 379 |
< |
|
| 380 |
< |
public boolean hasNext() { |
| 381 |
< |
return i.hasNext(); |
| 382 |
< |
} |
| 383 |
< |
|
| 384 |
< |
public V next() { |
| 385 |
< |
return i.next().getValue(); |
| 386 |
< |
} |
| 387 |
< |
|
| 388 |
< |
public void remove() { |
| 389 |
< |
i.remove(); |
| 390 |
< |
} |
| 374 |
> |
if (values == null) { |
| 375 |
> |
values = new AbstractCollection<V>() { |
| 376 |
> |
public Iterator<V> iterator() { |
| 377 |
> |
return new Iterator<V>() { |
| 378 |
> |
private Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 379 |
> |
|
| 380 |
> |
public boolean hasNext() { |
| 381 |
> |
return i.hasNext(); |
| 382 |
> |
} |
| 383 |
> |
|
| 384 |
> |
public V next() { |
| 385 |
> |
return i.next().getValue(); |
| 386 |
> |
} |
| 387 |
> |
|
| 388 |
> |
public void remove() { |
| 389 |
> |
i.remove(); |
| 390 |
> |
} |
| 391 |
|
}; |
| 392 |
|
} |
| 393 |
|
|
| 394 |
< |
public int size() { |
| 395 |
< |
return AbstractMap.this.size(); |
| 396 |
< |
} |
| 397 |
< |
|
| 398 |
< |
public boolean contains(Object v) { |
| 399 |
< |
return AbstractMap.this.containsValue(v); |
| 400 |
< |
} |
| 401 |
< |
}; |
| 402 |
< |
} |
| 403 |
< |
return values; |
| 394 |
> |
public int size() { |
| 395 |
> |
return AbstractMap.this.size(); |
| 396 |
> |
} |
| 397 |
> |
|
| 398 |
> |
public boolean isEmpty() { |
| 399 |
> |
return AbstractMap.this.isEmpty(); |
| 400 |
> |
} |
| 401 |
> |
|
| 402 |
> |
public void clear() { |
| 403 |
> |
AbstractMap.this.clear(); |
| 404 |
> |
} |
| 405 |
> |
|
| 406 |
> |
public boolean contains(Object v) { |
| 407 |
> |
return AbstractMap.this.containsValue(v); |
| 408 |
> |
} |
| 409 |
> |
}; |
| 410 |
> |
} |
| 411 |
> |
return values; |
| 412 |
|
} |
| 413 |
|
|
| 414 |
|
public abstract Set<Entry<K,V>> entrySet(); |
| 417 |
|
// Comparison and hashing |
| 418 |
|
|
| 419 |
|
/** |
| 420 |
< |
* {@inheritDoc} |
| 420 |
> |
* Compares the specified object with this map for equality. Returns |
| 421 |
> |
* <tt>true</tt> if the given object is also a map and the two maps |
| 422 |
> |
* represent the same mappings. More formally, two maps <tt>m1</tt> and |
| 423 |
> |
* <tt>m2</tt> represent the same mappings if |
| 424 |
> |
* <tt>m1.entrySet().equals(m2.entrySet())</tt>. This ensures that the |
| 425 |
> |
* <tt>equals</tt> method works properly across different implementations |
| 426 |
> |
* of the <tt>Map</tt> interface. |
| 427 |
|
* |
| 428 |
|
* <p>This implementation first checks if the specified object is this map; |
| 429 |
|
* if so it returns <tt>true</tt>. Then, it checks if the specified |
| 433 |
|
* contains each mapping that this map contains. If the specified map |
| 434 |
|
* fails to contain such a mapping, <tt>false</tt> is returned. If the |
| 435 |
|
* iteration completes, <tt>true</tt> is returned. |
| 436 |
+ |
* |
| 437 |
+ |
* @param o object to be compared for equality with this map |
| 438 |
+ |
* @return <tt>true</tt> if the specified object is equal to this map |
| 439 |
|
*/ |
| 440 |
|
public boolean equals(Object o) { |
| 441 |
< |
if (o == this) |
| 442 |
< |
return true; |
| 441 |
> |
if (o == this) |
| 442 |
> |
return true; |
| 443 |
|
|
| 444 |
< |
if (!(o instanceof Map)) |
| 445 |
< |
return false; |
| 446 |
< |
Map<K,V> t = (Map<K,V>) o; |
| 447 |
< |
if (t.size() != size()) |
| 448 |
< |
return false; |
| 444 |
> |
if (!(o instanceof Map)) |
| 445 |
> |
return false; |
| 446 |
> |
Map<K,V> m = (Map<K,V>) o; |
| 447 |
> |
if (m.size() != size()) |
| 448 |
> |
return false; |
| 449 |
|
|
| 450 |
|
try { |
| 451 |
|
Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 452 |
|
while (i.hasNext()) { |
| 453 |
|
Entry<K,V> e = i.next(); |
| 454 |
< |
K key = e.getKey(); |
| 454 |
> |
K key = e.getKey(); |
| 455 |
|
V value = e.getValue(); |
| 456 |
|
if (value == null) { |
| 457 |
< |
if (!(t.get(key)==null && t.containsKey(key))) |
| 457 |
> |
if (!(m.get(key)==null && m.containsKey(key))) |
| 458 |
|
return false; |
| 459 |
|
} else { |
| 460 |
< |
if (!value.equals(t.get(key))) |
| 460 |
> |
if (!value.equals(m.get(key))) |
| 461 |
|
return false; |
| 462 |
|
} |
| 463 |
|
} |
| 467 |
|
return false; |
| 468 |
|
} |
| 469 |
|
|
| 470 |
< |
return true; |
| 470 |
> |
return true; |
| 471 |
|
} |
| 472 |
|
|
| 473 |
|
/** |
| 474 |
< |
* {@inheritDoc} |
| 474 |
> |
* Returns the hash code value for this map. The hash code of a map is |
| 475 |
> |
* defined to be the sum of the hash codes of each entry in the map's |
| 476 |
> |
* <tt>entrySet()</tt> view. This ensures that <tt>m1.equals(m2)</tt> |
| 477 |
> |
* implies that <tt>m1.hashCode()==m2.hashCode()</tt> for any two maps |
| 478 |
> |
* <tt>m1</tt> and <tt>m2</tt>, as required by the general contract of |
| 479 |
> |
* {@link Object#hashCode}. |
| 480 |
|
* |
| 481 |
|
* <p>This implementation iterates over <tt>entrySet()</tt>, calling |
| 482 |
< |
* <tt>hashCode()</tt> on each element (entry) in the set, and |
| 483 |
< |
* adding up the results. |
| 482 |
> |
* {@link Map.Entry#hashCode hashCode()} on each element (entry) in the |
| 483 |
> |
* set, and adding up the results. |
| 484 |
|
* |
| 485 |
+ |
* @return the hash code value for this map |
| 486 |
|
* @see Map.Entry#hashCode() |
| 442 |
– |
* @see Object#hashCode() |
| 487 |
|
* @see Object#equals(Object) |
| 488 |
|
* @see Set#equals(Object) |
| 489 |
|
*/ |
| 490 |
|
public int hashCode() { |
| 491 |
< |
int h = 0; |
| 492 |
< |
Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 493 |
< |
while (i.hasNext()) |
| 494 |
< |
h += i.next().hashCode(); |
| 495 |
< |
return h; |
| 491 |
> |
int h = 0; |
| 492 |
> |
Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 493 |
> |
while (i.hasNext()) |
| 494 |
> |
h += i.next().hashCode(); |
| 495 |
> |
return h; |
| 496 |
|
} |
| 497 |
|
|
| 498 |
|
/** |
| 503 |
|
* <tt>", "</tt> (comma and space). Each key-value mapping is rendered as |
| 504 |
|
* the key followed by an equals sign (<tt>"="</tt>) followed by the |
| 505 |
|
* associated value. Keys and values are converted to strings as by |
| 506 |
< |
* <tt>String.valueOf(Object)</tt>.<p> |
| 506 |
> |
* {@link String#valueOf(Object)}. |
| 507 |
|
* |
| 508 |
< |
* This implementation creates an empty string buffer, appends a left |
| 465 |
< |
* brace, and iterates over the map's <tt>entrySet</tt> view, appending |
| 466 |
< |
* the string representation of each <tt>map.entry</tt> in turn. After |
| 467 |
< |
* appending each entry except the last, the string <tt>", "</tt> is |
| 468 |
< |
* appended. Finally a right brace is appended. A string is obtained |
| 469 |
< |
* from the stringbuffer, and returned. |
| 470 |
< |
* |
| 471 |
< |
* @return a String representation of this map. |
| 508 |
> |
* @return a string representation of this map |
| 509 |
|
*/ |
| 510 |
|
public String toString() { |
| 511 |
< |
StringBuffer buf = new StringBuffer(); |
| 512 |
< |
buf.append("{"); |
| 513 |
< |
|
| 514 |
< |
Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 515 |
< |
boolean hasNext = i.hasNext(); |
| 516 |
< |
while (hasNext) { |
| 517 |
< |
Entry<K,V> e = i.next(); |
| 518 |
< |
K key = e.getKey(); |
| 511 |
> |
Iterator<Entry<K,V>> i = entrySet().iterator(); |
| 512 |
> |
if (! i.hasNext()) |
| 513 |
> |
return "{}"; |
| 514 |
> |
|
| 515 |
> |
StringBuilder sb = new StringBuilder(); |
| 516 |
> |
sb.append('{'); |
| 517 |
> |
for (;;) { |
| 518 |
> |
Entry<K,V> e = i.next(); |
| 519 |
> |
K key = e.getKey(); |
| 520 |
|
V value = e.getValue(); |
| 521 |
< |
if (key == this) |
| 522 |
< |
buf.append("(this Map)"); |
| 523 |
< |
else |
| 524 |
< |
buf.append(key); |
| 525 |
< |
buf.append("="); |
| 526 |
< |
if (value == this) |
| 489 |
< |
buf.append("(this Map)"); |
| 490 |
< |
else |
| 491 |
< |
buf.append(value); |
| 492 |
< |
hasNext = i.hasNext(); |
| 493 |
< |
if (hasNext) |
| 494 |
< |
buf.append(", "); |
| 521 |
> |
sb.append(key == this ? "(this Map)" : key); |
| 522 |
> |
sb.append('='); |
| 523 |
> |
sb.append(value == this ? "(this Map)" : value); |
| 524 |
> |
if (! i.hasNext()) |
| 525 |
> |
return sb.append('}').toString(); |
| 526 |
> |
sb.append(", "); |
| 527 |
|
} |
| 496 |
– |
|
| 497 |
– |
buf.append("}"); |
| 498 |
– |
return buf.toString(); |
| 528 |
|
} |
| 529 |
|
|
| 530 |
|
/** |
| 545 |
|
* Test for equality, checking for nulls. |
| 546 |
|
*/ |
| 547 |
|
private static boolean eq(Object o1, Object o2) { |
| 548 |
< |
return (o1 == null ? o2 == null : o1.equals(o2)); |
| 548 |
> |
return o1 == null ? o2 == null : o1.equals(o2); |
| 549 |
|
} |
| 550 |
|
|
| 551 |
|
// Implementation Note: SimpleEntry and SimpleImmutableEntry |
| 562 |
|
* facilitates the process of building custom map |
| 563 |
|
* implementations. For example, it may be convenient to return |
| 564 |
|
* arrays of <tt>SimpleEntry</tt> instances in method |
| 565 |
< |
* <tt>Map.entrySet().toArray</tt> |
| 565 |
> |
* <tt>Map.entrySet().toArray</tt>. |
| 566 |
> |
* |
| 567 |
> |
* @since 1.6 |
| 568 |
|
*/ |
| 569 |
< |
public static class SimpleEntry<K,V> implements Entry<K,V> { |
| 570 |
< |
private final K key; |
| 571 |
< |
private V value; |
| 569 |
> |
public static class SimpleEntry<K,V> |
| 570 |
> |
implements Entry<K,V>, java.io.Serializable |
| 571 |
> |
{ |
| 572 |
> |
private static final long serialVersionUID = -8499721149061103585L; |
| 573 |
> |
|
| 574 |
> |
private final K key; |
| 575 |
> |
private V value; |
| 576 |
|
|
| 577 |
|
/** |
| 578 |
|
* Creates an entry representing a mapping from the specified |
| 581 |
|
* @param key the key represented by this entry |
| 582 |
|
* @param value the value represented by this entry |
| 583 |
|
*/ |
| 584 |
< |
public SimpleEntry(K key, V value) { |
| 585 |
< |
this.key = key; |
| 584 |
> |
public SimpleEntry(K key, V value) { |
| 585 |
> |
this.key = key; |
| 586 |
|
this.value = value; |
| 587 |
< |
} |
| 587 |
> |
} |
| 588 |
|
|
| 589 |
|
/** |
| 590 |
|
* Creates an entry representing the same mapping as the |
| 591 |
|
* specified entry. |
| 592 |
|
* |
| 593 |
< |
* @param entry the entry to copy. |
| 593 |
> |
* @param entry the entry to copy |
| 594 |
|
*/ |
| 595 |
< |
public SimpleEntry(Entry<? extends K, ? extends V> entry) { |
| 596 |
< |
this.key = entry.getKey(); |
| 595 |
> |
public SimpleEntry(Entry<? extends K, ? extends V> entry) { |
| 596 |
> |
this.key = entry.getKey(); |
| 597 |
|
this.value = entry.getValue(); |
| 598 |
< |
} |
| 598 |
> |
} |
| 599 |
> |
|
| 600 |
> |
/** |
| 601 |
> |
* Returns the key corresponding to this entry. |
| 602 |
> |
* |
| 603 |
> |
* @return the key corresponding to this entry |
| 604 |
> |
*/ |
| 605 |
> |
public K getKey() { |
| 606 |
> |
return key; |
| 607 |
> |
} |
| 608 |
> |
|
| 609 |
> |
/** |
| 610 |
> |
* Returns the value corresponding to this entry. |
| 611 |
> |
* |
| 612 |
> |
* @return the value corresponding to this entry |
| 613 |
> |
*/ |
| 614 |
> |
public V getValue() { |
| 615 |
> |
return value; |
| 616 |
> |
} |
| 617 |
> |
|
| 618 |
> |
/** |
| 619 |
> |
* Replaces the value corresponding to this entry with the specified |
| 620 |
> |
* value. |
| 621 |
> |
* |
| 622 |
> |
* @param value new value to be stored in this entry |
| 623 |
> |
* @return the old value corresponding to the entry |
| 624 |
> |
*/ |
| 625 |
> |
public V setValue(V value) { |
| 626 |
> |
V oldValue = this.value; |
| 627 |
> |
this.value = value; |
| 628 |
> |
return oldValue; |
| 629 |
> |
} |
| 630 |
> |
|
| 631 |
> |
/** |
| 632 |
> |
* Compares the specified object with this entry for equality. |
| 633 |
> |
* Returns {@code true} if the given object is also a map entry and |
| 634 |
> |
* the two entries represent the same mapping. More formally, two |
| 635 |
> |
* entries {@code e1} and {@code e2} represent the same mapping |
| 636 |
> |
* if<pre> |
| 637 |
> |
* (e1.getKey()==null ? |
| 638 |
> |
* e2.getKey()==null : |
| 639 |
> |
* e1.getKey().equals(e2.getKey())) |
| 640 |
> |
* && |
| 641 |
> |
* (e1.getValue()==null ? |
| 642 |
> |
* e2.getValue()==null : |
| 643 |
> |
* e1.getValue().equals(e2.getValue()))</pre> |
| 644 |
> |
* This ensures that the {@code equals} method works properly across |
| 645 |
> |
* different implementations of the {@code Map.Entry} interface. |
| 646 |
> |
* |
| 647 |
> |
* @param o object to be compared for equality with this map entry |
| 648 |
> |
* @return {@code true} if the specified object is equal to this map |
| 649 |
> |
* entry |
| 650 |
> |
* @see #hashCode |
| 651 |
> |
*/ |
| 652 |
> |
public boolean equals(Object o) { |
| 653 |
> |
if (!(o instanceof Map.Entry)) |
| 654 |
> |
return false; |
| 655 |
> |
Map.Entry e = (Map.Entry)o; |
| 656 |
> |
return eq(key, e.getKey()) && eq(value, e.getValue()); |
| 657 |
> |
} |
| 658 |
|
|
| 659 |
< |
/** |
| 660 |
< |
* Returns the key corresponding to this entry. |
| 661 |
< |
* |
| 662 |
< |
* @return the key corresponding to this entry |
| 663 |
< |
*/ |
| 664 |
< |
public K getKey() { |
| 665 |
< |
return key; |
| 666 |
< |
} |
| 667 |
< |
|
| 668 |
< |
/** |
| 669 |
< |
* Returns the value corresponding to this entry. |
| 670 |
< |
* |
| 671 |
< |
* @return the value corresponding to this entry |
| 672 |
< |
*/ |
| 673 |
< |
public V getValue() { |
| 674 |
< |
return value; |
| 675 |
< |
} |
| 582 |
< |
|
| 583 |
< |
/** |
| 584 |
< |
* Replaces the value corresponding to this entry with the specified |
| 585 |
< |
* value. |
| 586 |
< |
* |
| 587 |
< |
* @param value new value to be stored in this entry |
| 588 |
< |
* @return the old value corresponding to the entry |
| 589 |
< |
*/ |
| 590 |
< |
public V setValue(V value) { |
| 591 |
< |
V oldValue = this.value; |
| 592 |
< |
this.value = value; |
| 593 |
< |
return oldValue; |
| 594 |
< |
} |
| 595 |
< |
|
| 596 |
< |
public boolean equals(Object o) { |
| 597 |
< |
if (!(o instanceof Map.Entry)) |
| 598 |
< |
return false; |
| 599 |
< |
Map.Entry e = (Map.Entry)o; |
| 600 |
< |
return eq(key, e.getKey()) && eq(value, e.getValue()); |
| 601 |
< |
} |
| 602 |
< |
|
| 603 |
< |
public int hashCode() { |
| 604 |
< |
return ((key == null) ? 0 : key.hashCode()) ^ |
| 605 |
< |
((value == null) ? 0 : value.hashCode()); |
| 606 |
< |
} |
| 659 |
> |
/** |
| 660 |
> |
* Returns the hash code value for this map entry. The hash code |
| 661 |
> |
* of a map entry {@code e} is defined to be: <pre> |
| 662 |
> |
* (e.getKey()==null ? 0 : e.getKey().hashCode()) ^ |
| 663 |
> |
* (e.getValue()==null ? 0 : e.getValue().hashCode())</pre> |
| 664 |
> |
* This ensures that {@code e1.equals(e2)} implies that |
| 665 |
> |
* {@code e1.hashCode()==e2.hashCode()} for any two Entries |
| 666 |
> |
* {@code e1} and {@code e2}, as required by the general |
| 667 |
> |
* contract of {@link Object#hashCode}. |
| 668 |
> |
* |
| 669 |
> |
* @return the hash code value for this map entry |
| 670 |
> |
* @see #equals |
| 671 |
> |
*/ |
| 672 |
> |
public int hashCode() { |
| 673 |
> |
return (key == null ? 0 : key.hashCode()) ^ |
| 674 |
> |
(value == null ? 0 : value.hashCode()); |
| 675 |
> |
} |
| 676 |
|
|
| 677 |
|
/** |
| 678 |
|
* Returns a String representation of this map entry. This |
| 682 |
|
* |
| 683 |
|
* @return a String representation of this map entry |
| 684 |
|
*/ |
| 685 |
< |
public String toString() { |
| 686 |
< |
return key + "=" + value; |
| 687 |
< |
} |
| 685 |
> |
public String toString() { |
| 686 |
> |
return key + "=" + value; |
| 687 |
> |
} |
| 688 |
|
|
| 689 |
|
} |
| 690 |
|
|
| 691 |
|
/** |
| 692 |
< |
* An Entry maintaining an immutable key and value, This class |
| 692 |
> |
* An Entry maintaining an immutable key and value. This class |
| 693 |
|
* does not support method <tt>setValue</tt>. This class may be |
| 694 |
|
* convenient in methods that return thread-safe snapshots of |
| 695 |
|
* key-value mappings. |
| 696 |
+ |
* |
| 697 |
+ |
* @since 1.6 |
| 698 |
|
*/ |
| 699 |
< |
public static class SimpleImmutableEntry<K,V> implements Entry<K,V> { |
| 700 |
< |
private final K key; |
| 701 |
< |
private final V value; |
| 699 |
> |
public static class SimpleImmutableEntry<K,V> |
| 700 |
> |
implements Entry<K,V>, java.io.Serializable |
| 701 |
> |
{ |
| 702 |
> |
private static final long serialVersionUID = 7138329143949025153L; |
| 703 |
> |
|
| 704 |
> |
private final K key; |
| 705 |
> |
private final V value; |
| 706 |
|
|
| 707 |
|
/** |
| 708 |
|
* Creates an entry representing a mapping from the specified |
| 711 |
|
* @param key the key represented by this entry |
| 712 |
|
* @param value the value represented by this entry |
| 713 |
|
*/ |
| 714 |
< |
public SimpleImmutableEntry(K key, V value) { |
| 715 |
< |
this.key = key; |
| 714 |
> |
public SimpleImmutableEntry(K key, V value) { |
| 715 |
> |
this.key = key; |
| 716 |
|
this.value = value; |
| 717 |
< |
} |
| 717 |
> |
} |
| 718 |
|
|
| 719 |
|
/** |
| 720 |
|
* Creates an entry representing the same mapping as the |
| 722 |
|
* |
| 723 |
|
* @param entry the entry to copy |
| 724 |
|
*/ |
| 725 |
< |
public SimpleImmutableEntry(Entry<? extends K, ? extends V> entry) { |
| 726 |
< |
this.key = entry.getKey(); |
| 725 |
> |
public SimpleImmutableEntry(Entry<? extends K, ? extends V> entry) { |
| 726 |
> |
this.key = entry.getKey(); |
| 727 |
|
this.value = entry.getValue(); |
| 728 |
< |
} |
| 728 |
> |
} |
| 729 |
> |
|
| 730 |
> |
/** |
| 731 |
> |
* Returns the key corresponding to this entry. |
| 732 |
> |
* |
| 733 |
> |
* @return the key corresponding to this entry |
| 734 |
> |
*/ |
| 735 |
> |
public K getKey() { |
| 736 |
> |
return key; |
| 737 |
> |
} |
| 738 |
|
|
| 739 |
< |
/** |
| 740 |
< |
* Returns the key corresponding to this entry. |
| 741 |
< |
* |
| 742 |
< |
* @return the key corresponding to this entry |
| 743 |
< |
*/ |
| 744 |
< |
public K getKey() { |
| 745 |
< |
return key; |
| 746 |
< |
} |
| 747 |
< |
|
| 748 |
< |
/** |
| 749 |
< |
* Returns the value corresponding to this entry. |
| 750 |
< |
* |
| 667 |
< |
* @return the value corresponding to this entry |
| 668 |
< |
*/ |
| 669 |
< |
public V getValue() { |
| 670 |
< |
return value; |
| 671 |
< |
} |
| 672 |
< |
|
| 673 |
< |
/** |
| 674 |
< |
* Replaces the value corresponding to this entry with the specified |
| 675 |
< |
* value (optional operation). This implementation simply throws |
| 739 |
> |
/** |
| 740 |
> |
* Returns the value corresponding to this entry. |
| 741 |
> |
* |
| 742 |
> |
* @return the value corresponding to this entry |
| 743 |
> |
*/ |
| 744 |
> |
public V getValue() { |
| 745 |
> |
return value; |
| 746 |
> |
} |
| 747 |
> |
|
| 748 |
> |
/** |
| 749 |
> |
* Replaces the value corresponding to this entry with the specified |
| 750 |
> |
* value (optional operation). This implementation simply throws |
| 751 |
|
* <tt>UnsupportedOperationException</tt>, as this class implements |
| 752 |
|
* an <i>immutable</i> map entry. |
| 753 |
< |
* |
| 754 |
< |
* @param value new value to be stored in this entry |
| 755 |
< |
* @return (Does not return) |
| 756 |
< |
* @throws UnsupportedOperationException always |
| 753 |
> |
* |
| 754 |
> |
* @param value new value to be stored in this entry |
| 755 |
> |
* @return (Does not return) |
| 756 |
> |
* @throws UnsupportedOperationException always |
| 757 |
|
*/ |
| 758 |
< |
public V setValue(V value) { |
| 758 |
> |
public V setValue(V value) { |
| 759 |
|
throw new UnsupportedOperationException(); |
| 760 |
|
} |
| 761 |
|
|
| 762 |
< |
public boolean equals(Object o) { |
| 763 |
< |
if (!(o instanceof Map.Entry)) |
| 764 |
< |
return false; |
| 765 |
< |
Map.Entry e = (Map.Entry)o; |
| 766 |
< |
return eq(key, e.getKey()) && eq(value, e.getValue()); |
| 767 |
< |
} |
| 768 |
< |
|
| 769 |
< |
public int hashCode() { |
| 770 |
< |
return ((key == null) ? 0 : key.hashCode()) ^ |
| 771 |
< |
((value == null) ? 0 : value.hashCode()); |
| 772 |
< |
} |
| 762 |
> |
/** |
| 763 |
> |
* Compares the specified object with this entry for equality. |
| 764 |
> |
* Returns {@code true} if the given object is also a map entry and |
| 765 |
> |
* the two entries represent the same mapping. More formally, two |
| 766 |
> |
* entries {@code e1} and {@code e2} represent the same mapping |
| 767 |
> |
* if<pre> |
| 768 |
> |
* (e1.getKey()==null ? |
| 769 |
> |
* e2.getKey()==null : |
| 770 |
> |
* e1.getKey().equals(e2.getKey())) |
| 771 |
> |
* && |
| 772 |
> |
* (e1.getValue()==null ? |
| 773 |
> |
* e2.getValue()==null : |
| 774 |
> |
* e1.getValue().equals(e2.getValue()))</pre> |
| 775 |
> |
* This ensures that the {@code equals} method works properly across |
| 776 |
> |
* different implementations of the {@code Map.Entry} interface. |
| 777 |
> |
* |
| 778 |
> |
* @param o object to be compared for equality with this map entry |
| 779 |
> |
* @return {@code true} if the specified object is equal to this map |
| 780 |
> |
* entry |
| 781 |
> |
* @see #hashCode |
| 782 |
> |
*/ |
| 783 |
> |
public boolean equals(Object o) { |
| 784 |
> |
if (!(o instanceof Map.Entry)) |
| 785 |
> |
return false; |
| 786 |
> |
Map.Entry e = (Map.Entry)o; |
| 787 |
> |
return eq(key, e.getKey()) && eq(value, e.getValue()); |
| 788 |
> |
} |
| 789 |
> |
|
| 790 |
> |
/** |
| 791 |
> |
* Returns the hash code value for this map entry. The hash code |
| 792 |
> |
* of a map entry {@code e} is defined to be: <pre> |
| 793 |
> |
* (e.getKey()==null ? 0 : e.getKey().hashCode()) ^ |
| 794 |
> |
* (e.getValue()==null ? 0 : e.getValue().hashCode())</pre> |
| 795 |
> |
* This ensures that {@code e1.equals(e2)} implies that |
| 796 |
> |
* {@code e1.hashCode()==e2.hashCode()} for any two Entries |
| 797 |
> |
* {@code e1} and {@code e2}, as required by the general |
| 798 |
> |
* contract of {@link Object#hashCode}. |
| 799 |
> |
* |
| 800 |
> |
* @return the hash code value for this map entry |
| 801 |
> |
* @see #equals |
| 802 |
> |
*/ |
| 803 |
> |
public int hashCode() { |
| 804 |
> |
return (key == null ? 0 : key.hashCode()) ^ |
| 805 |
> |
(value == null ? 0 : value.hashCode()); |
| 806 |
> |
} |
| 807 |
|
|
| 808 |
|
/** |
| 809 |
|
* Returns a String representation of this map entry. This |
| 813 |
|
* |
| 814 |
|
* @return a String representation of this map entry |
| 815 |
|
*/ |
| 816 |
< |
public String toString() { |
| 817 |
< |
return key + "=" + value; |
| 818 |
< |
} |
| 816 |
> |
public String toString() { |
| 817 |
> |
return key + "=" + value; |
| 818 |
> |
} |
| 819 |
|
|
| 820 |
|
} |
| 821 |
|
|
