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/* |
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* %W% %E% |
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* |
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* Copyright 2006 Sun Microsystems, Inc. All rights reserved. |
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* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
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*/ |
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|
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package java.util; |
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import java.util.*; // for javadoc (till 6280605 is fixed) |
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|
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/** |
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* A Red-Black tree based {@link NavigableMap} implementation. |
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* The map is sorted according to the {@linkplain Comparable natural |
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* ordering} of its keys, or by a {@link Comparator} provided at map |
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* creation time, depending on which constructor is used. |
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* |
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* <p>This implementation provides guaranteed log(n) time cost for the |
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* <tt>containsKey</tt>, <tt>get</tt>, <tt>put</tt> and <tt>remove</tt> |
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* operations. Algorithms are adaptations of those in Cormen, Leiserson, and |
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* Rivest's <I>Introduction to Algorithms</I>. |
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* |
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* <p>Note that the ordering maintained by a sorted map (whether or not an |
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* explicit comparator is provided) must be <i>consistent with equals</i> if |
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* this sorted map is to correctly implement the <tt>Map</tt> interface. (See |
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* <tt>Comparable</tt> or <tt>Comparator</tt> for a precise definition of |
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* <i>consistent with equals</i>.) This is so because the <tt>Map</tt> |
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* interface is defined in terms of the equals operation, but a map performs |
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* all key comparisons using its <tt>compareTo</tt> (or <tt>compare</tt>) |
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* method, so two keys that are deemed equal by this method are, from the |
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* standpoint of the sorted map, equal. The behavior of a sorted map |
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* <i>is</i> well-defined even if its ordering is inconsistent with equals; it |
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* just fails to obey the general contract of the <tt>Map</tt> interface. |
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* |
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* <p><strong>Note that this implementation is not synchronized.</strong> |
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* If multiple threads access a map concurrently, and at least one of the |
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* threads modifies the map structurally, it <i>must</i> be synchronized |
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* externally. (A structural modification is any operation that adds or |
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* deletes one or more mappings; merely changing the value associated |
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* with an existing key is not a structural modification.) This is |
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* typically accomplished by synchronizing on some object that naturally |
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* encapsulates the map. |
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* If no such object exists, the map should be "wrapped" using the |
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* {@link Collections#synchronizedSortedMap Collections.synchronizedSortedMap} |
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* method. This is best done at creation time, to prevent accidental |
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* unsynchronized access to the map: <pre> |
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* SortedMap m = Collections.synchronizedSortedMap(new TreeMap(...));</pre> |
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* |
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* <p>The iterators returned by the <tt>iterator</tt> method of the collections |
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* returned by all of this class's "collection view methods" are |
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* <i>fail-fast</i>: if the map is structurally modified at any time after the |
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* iterator is created, in any way except through the iterator's own |
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* <tt>remove</tt> method, the iterator will throw a {@link |
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* ConcurrentModificationException}. Thus, in the face of concurrent |
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* modification, the iterator fails quickly and cleanly, rather than risking |
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* arbitrary, non-deterministic behavior at an undetermined time in the future. |
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* |
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* <p>Note that the fail-fast behavior of an iterator cannot be guaranteed |
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* as it is, generally speaking, impossible to make any hard guarantees in the |
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* presence of unsynchronized concurrent modification. Fail-fast iterators |
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* throw <tt>ConcurrentModificationException</tt> on a best-effort basis. |
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* Therefore, it would be wrong to write a program that depended on this |
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* exception for its correctness: <i>the fail-fast behavior of iterators |
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* should be used only to detect bugs.</i> |
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* |
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* <p>All <tt>Map.Entry</tt> pairs returned by methods in this class |
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* and its views represent snapshots of mappings at the time they were |
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* produced. They do <em>not</em> support the <tt>Entry.setValue</tt> |
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* method. (Note however that it is possible to change mappings in the |
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* associated map using <tt>put</tt>.) |
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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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* 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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* @param <V> the type of mapped values |
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* |
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* @author Josh Bloch and Doug Lea |
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* @version %I%, %G% |
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* @see Map |
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* @see HashMap |
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* @see Hashtable |
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* @see Comparable |
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* @see Comparator |
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* @see Collection |
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* @since 1.2 |
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*/ |
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|
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public class TreeMap<K,V> |
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extends AbstractMap<K,V> |
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implements NavigableMap<K,V>, Cloneable, java.io.Serializable |
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{ |
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/** |
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* The comparator used to maintain order in this tree map, or |
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* null if it uses the natural ordering of its keys. |
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* |
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* @serial |
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*/ |
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private Comparator<? super K> comparator = null; |
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|
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private transient Entry<K,V> root = null; |
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|
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/** |
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* The number of entries in the tree |
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*/ |
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private transient int size = 0; |
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|
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/** |
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* The number of structural modifications to the tree. |
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*/ |
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private transient int modCount = 0; |
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|
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private void incrementSize() { modCount++; size++; } |
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private void decrementSize() { modCount++; size--; } |
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|
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/** |
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* Constructs a new, empty tree map, using the natural ordering of its |
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* keys. All keys inserted into the map must implement the {@link |
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* Comparable} interface. Furthermore, all such keys must be |
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* <i>mutually comparable</i>: <tt>k1.compareTo(k2)</tt> must not throw |
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* a <tt>ClassCastException</tt> for any keys <tt>k1</tt> and |
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* <tt>k2</tt> in the map. If the user attempts to put a key into the |
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* map that violates this constraint (for example, the user attempts to |
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* put a string key into a map whose keys are integers), the |
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* <tt>put(Object key, Object value)</tt> call will throw a |
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* <tt>ClassCastException</tt>. |
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*/ |
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public TreeMap() { |
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} |
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|
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/** |
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* Constructs a new, empty tree map, ordered according to the given |
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* comparator. All keys inserted into the map must be <i>mutually |
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* comparable</i> by the given comparator: <tt>comparator.compare(k1, |
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* k2)</tt> must not throw a <tt>ClassCastException</tt> for any keys |
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* <tt>k1</tt> and <tt>k2</tt> in the map. If the user attempts to put |
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* a key into the map that violates this constraint, the <tt>put(Object |
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* key, Object value)</tt> call will throw a |
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* <tt>ClassCastException</tt>. |
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* |
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* @param comparator the comparator that will be used to order this map. |
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* If <tt>null</tt>, the {@linkplain Comparable natural |
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* ordering} of the keys will be used. |
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*/ |
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public TreeMap(Comparator<? super K> comparator) { |
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this.comparator = comparator; |
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} |
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|
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/** |
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* Constructs a new tree map containing the same mappings as the given |
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* map, ordered according to the <i>natural ordering</i> of its keys. |
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* All keys inserted into the new map must implement the {@link |
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* Comparable} interface. Furthermore, all such keys must be |
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* <i>mutually comparable</i>: <tt>k1.compareTo(k2)</tt> must not throw |
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* a <tt>ClassCastException</tt> for any keys <tt>k1</tt> and |
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* <tt>k2</tt> in the map. This method runs in n*log(n) time. |
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* |
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* @param m the map whose mappings are to be placed in this map |
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* @throws ClassCastException if the keys in m are not {@link Comparable}, |
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* or are not mutually comparable |
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* @throws NullPointerException if the specified map is null |
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*/ |
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public TreeMap(Map<? extends K, ? extends V> m) { |
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putAll(m); |
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} |
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|
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/** |
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* Constructs a new tree map containing the same mappings and |
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* using the same ordering as the specified sorted map. This |
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* method runs in linear time. |
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* |
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* @param m the sorted map whose mappings are to be placed in this map, |
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* and whose comparator is to be used to sort this map |
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* @throws NullPointerException if the specified map is null |
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*/ |
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public TreeMap(SortedMap<K, ? extends V> m) { |
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comparator = m.comparator(); |
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try { |
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buildFromSorted(m.size(), m.entrySet().iterator(), null, null); |
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} catch (java.io.IOException cannotHappen) { |
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} catch (ClassNotFoundException cannotHappen) { |
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} |
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} |
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|
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|
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// Query Operations |
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|
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/** |
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* Returns the number of key-value mappings in this map. |
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* |
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* @return the number of key-value mappings in this map |
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*/ |
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public int size() { |
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return size; |
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} |
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|
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/** |
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* Returns <tt>true</tt> if this map contains a mapping for the specified |
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* key. |
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* |
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* @param key key whose presence in this map is to be tested |
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* @return <tt>true</tt> if this map contains a mapping for the |
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* specified key |
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* @throws ClassCastException if the specified key cannot be compared |
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* with the keys currently in the map |
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* @throws NullPointerException if the specified key is null |
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* and this map uses natural ordering, or its comparator |
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* does not permit null keys |
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*/ |
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public boolean containsKey(Object key) { |
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return getEntry(key) != null; |
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} |
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|
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/** |
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* Returns <tt>true</tt> if this map maps one or more keys to the |
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* specified value. More formally, returns <tt>true</tt> if and only if |
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* this map contains at least one mapping to a value <tt>v</tt> such |
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* that <tt>(value==null ? v==null : value.equals(v))</tt>. This |
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* operation will probably require time linear in the map size for |
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* most implementations. |
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* |
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* @param value value whose presence in this map is to be tested |
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* @return <tt>true</tt> if a mapping to <tt>value</tt> exists; |
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* <tt>false</tt> otherwise |
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* @since 1.2 |
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*/ |
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public boolean containsValue(Object value) { |
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return (root==null ? false : |
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(value==null ? valueSearchNull(root) |
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: valueSearchNonNull(root, value))); |
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} |
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|
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private boolean valueSearchNull(Entry n) { |
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if (n.value == null) |
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return true; |
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|
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// Check left and right subtrees for value |
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return (n.left != null && valueSearchNull(n.left)) || |
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(n.right != null && valueSearchNull(n.right)); |
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} |
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|
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private boolean valueSearchNonNull(Entry n, Object value) { |
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// Check this node for the value |
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if (value.equals(n.value)) |
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return true; |
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|
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// Check left and right subtrees for value |
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return (n.left != null && valueSearchNonNull(n.left, value)) || |
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(n.right != null && valueSearchNonNull(n.right, value)); |
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} |
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|
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/** |
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* Returns the value to which the specified key is mapped, |
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* or {@code null} if this map contains no mapping for the key. |
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* |
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* <p>More formally, if this map contains a mapping from a key |
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* {@code k} to a value {@code v} such that {@code key} compares |
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* equal to {@code k} according to the map's ordering, then this |
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* method returns {@code v}; otherwise it returns {@code null}. |
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* (There can be at most one such mapping.) |
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* |
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* <p>A return value of {@code null} does not <i>necessarily</i> |
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* indicate that the map contains no mapping for the key; it's also |
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* possible that the map explicitly maps the key to {@code null}. |
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* The {@link #containsKey containsKey} operation may be used to |
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* distinguish these two cases. |
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* |
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* @throws ClassCastException if the specified key cannot be compared |
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* with the keys currently in the map |
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* @throws NullPointerException if the specified key is null |
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* and this map uses natural ordering, or its comparator |
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* does not permit null keys |
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*/ |
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public V get(Object key) { |
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Entry<K,V> p = getEntry(key); |
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return (p==null ? null : p.value); |
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} |
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|
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public Comparator<? super K> comparator() { |
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return comparator; |
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} |
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|
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/** |
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* @throws NoSuchElementException {@inheritDoc} |
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*/ |
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public K firstKey() { |
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return key(getFirstEntry()); |
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} |
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|
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/** |
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* @throws NoSuchElementException {@inheritDoc} |
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*/ |
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public K lastKey() { |
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return key(getLastEntry()); |
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} |
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|
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/** |
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* Copies all of the mappings from the specified map to this map. |
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* These mappings replace any mappings that this map had for any |
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* of the keys currently in the specified map. |
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* |
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* @param map mappings to be stored in this map |
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* @throws ClassCastException if the class of a key or value in |
304 |
* the specified map prevents it from being stored in this map |
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* @throws NullPointerException if the specified map is null or |
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* the specified map contains a null key and this map does not |
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* permit null keys |
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*/ |
309 |
public void putAll(Map<? extends K, ? extends V> map) { |
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int mapSize = map.size(); |
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if (size==0 && mapSize!=0 && map instanceof SortedMap) { |
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Comparator c = ((SortedMap)map).comparator(); |
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if (c == comparator || (c != null && c.equals(comparator))) { |
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++modCount; |
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try { |
316 |
buildFromSorted(mapSize, map.entrySet().iterator(), |
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null, null); |
318 |
} catch (java.io.IOException cannotHappen) { |
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} catch (ClassNotFoundException cannotHappen) { |
320 |
} |
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return; |
322 |
} |
323 |
} |
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super.putAll(map); |
325 |
} |
326 |
|
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/** |
328 |
* Returns this map's entry for the given key, or <tt>null</tt> if the map |
329 |
* does not contain an entry for the key. |
330 |
* |
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* @return this map's entry for the given key, or <tt>null</tt> if the map |
332 |
* does not contain an entry for the key |
333 |
* @throws ClassCastException if the specified key cannot be compared |
334 |
* with the keys currently in the map |
335 |
* @throws NullPointerException if the specified key is null |
336 |
* and this map uses natural ordering, or its comparator |
337 |
* does not permit null keys |
338 |
*/ |
339 |
private Entry<K,V> getEntry(Object key) { |
340 |
// Offload comparator-based version for sake of performance |
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if (comparator != null) |
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return getEntryUsingComparator(key); |
343 |
Comparable<? super K> k = (Comparable<? super K>) key; |
344 |
Entry<K,V> p = root; |
345 |
while (p != null) { |
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int cmp = k.compareTo(p.key); |
347 |
if (cmp < 0) |
348 |
p = p.left; |
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else if (cmp > 0) |
350 |
p = p.right; |
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else |
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return p; |
353 |
} |
354 |
return null; |
355 |
} |
356 |
|
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/** |
358 |
* Version of getEntry using comparator. Split off from getEntry |
359 |
* for performance. (This is not worth doing for most methods, |
360 |
* that are less dependent on comparator performance, but is |
361 |
* worthwhile here.) |
362 |
*/ |
363 |
private Entry<K,V> getEntryUsingComparator(Object key) { |
364 |
K k = (K) key; |
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Comparator<? super K> cpr = comparator; |
366 |
Entry<K,V> p = root; |
367 |
while (p != null) { |
368 |
int cmp = cpr.compare(k, p.key); |
369 |
if (cmp < 0) |
370 |
p = p.left; |
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else if (cmp > 0) |
372 |
p = p.right; |
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else |
374 |
return p; |
375 |
} |
376 |
return null; |
377 |
} |
378 |
|
379 |
/** |
380 |
* Gets the entry corresponding to the specified key; if no such entry |
381 |
* exists, returns the entry for the least key greater than the specified |
382 |
* key; if no such entry exists (i.e., the greatest key in the Tree is less |
383 |
* than the specified key), returns <tt>null</tt>. |
384 |
*/ |
385 |
private Entry<K,V> getCeilingEntry(K key) { |
386 |
Entry<K,V> p = root; |
387 |
if (p==null) |
388 |
return null; |
389 |
|
390 |
while (true) { |
391 |
int cmp = compare(key, p.key); |
392 |
if (cmp < 0) { |
393 |
if (p.left != null) |
394 |
p = p.left; |
395 |
else |
396 |
return p; |
397 |
} else if (cmp > 0) { |
398 |
if (p.right != null) { |
399 |
p = p.right; |
400 |
} else { |
401 |
Entry<K,V> parent = p.parent; |
402 |
Entry<K,V> ch = p; |
403 |
while (parent != null && ch == parent.right) { |
404 |
ch = parent; |
405 |
parent = parent.parent; |
406 |
} |
407 |
return parent; |
408 |
} |
409 |
} else |
410 |
return p; |
411 |
} |
412 |
} |
413 |
|
414 |
/** |
415 |
* Gets the entry corresponding to the specified key; if no such entry |
416 |
* exists, returns the entry for the greatest key less than the specified |
417 |
* key; if no such entry exists, returns <tt>null</tt>. |
418 |
*/ |
419 |
private Entry<K,V> getFloorEntry(K key) { |
420 |
Entry<K,V> p = root; |
421 |
if (p==null) |
422 |
return null; |
423 |
|
424 |
while (true) { |
425 |
int cmp = compare(key, p.key); |
426 |
if (cmp > 0) { |
427 |
if (p.right != null) |
428 |
p = p.right; |
429 |
else |
430 |
return p; |
431 |
} else if (cmp < 0) { |
432 |
if (p.left != null) { |
433 |
p = p.left; |
434 |
} else { |
435 |
Entry<K,V> parent = p.parent; |
436 |
Entry<K,V> ch = p; |
437 |
while (parent != null && ch == parent.left) { |
438 |
ch = parent; |
439 |
parent = parent.parent; |
440 |
} |
441 |
return parent; |
442 |
} |
443 |
} else |
444 |
return p; |
445 |
|
446 |
} |
447 |
} |
448 |
|
449 |
/** |
450 |
* Gets the entry for the least key greater than the specified |
451 |
* key; if no such entry exists, returns the entry for the least |
452 |
* key greater than the specified key; if no such entry exists |
453 |
* returns <tt>null</tt>. |
454 |
*/ |
455 |
private Entry<K,V> getHigherEntry(K key) { |
456 |
Entry<K,V> p = root; |
457 |
if (p==null) |
458 |
return null; |
459 |
|
460 |
while (true) { |
461 |
int cmp = compare(key, p.key); |
462 |
if (cmp < 0) { |
463 |
if (p.left != null) |
464 |
p = p.left; |
465 |
else |
466 |
return p; |
467 |
} else { |
468 |
if (p.right != null) { |
469 |
p = p.right; |
470 |
} else { |
471 |
Entry<K,V> parent = p.parent; |
472 |
Entry<K,V> ch = p; |
473 |
while (parent != null && ch == parent.right) { |
474 |
ch = parent; |
475 |
parent = parent.parent; |
476 |
} |
477 |
return parent; |
478 |
} |
479 |
} |
480 |
} |
481 |
} |
482 |
|
483 |
/** |
484 |
* Returns the entry for the greatest key less than the specified key; if |
485 |
* no such entry exists (i.e., the least key in the Tree is greater than |
486 |
* the specified key), returns <tt>null</tt>. |
487 |
*/ |
488 |
private Entry<K,V> getLowerEntry(K key) { |
489 |
Entry<K,V> p = root; |
490 |
if (p==null) |
491 |
return null; |
492 |
|
493 |
while (true) { |
494 |
int cmp = compare(key, p.key); |
495 |
if (cmp > 0) { |
496 |
if (p.right != null) |
497 |
p = p.right; |
498 |
else |
499 |
return p; |
500 |
} else { |
501 |
if (p.left != null) { |
502 |
p = p.left; |
503 |
} else { |
504 |
Entry<K,V> parent = p.parent; |
505 |
Entry<K,V> ch = p; |
506 |
while (parent != null && ch == parent.left) { |
507 |
ch = parent; |
508 |
parent = parent.parent; |
509 |
} |
510 |
return parent; |
511 |
} |
512 |
} |
513 |
} |
514 |
} |
515 |
|
516 |
/** |
517 |
* Returns the key corresponding to the specified Entry. |
518 |
* @throws NoSuchElementException if the Entry is null |
519 |
*/ |
520 |
private static <K> K key(Entry<K,?> e) { |
521 |
if (e==null) |
522 |
throw new NoSuchElementException(); |
523 |
return e.key; |
524 |
} |
525 |
|
526 |
/** |
527 |
* Associates the specified value with the specified key in this map. |
528 |
* If the map previously contained a mapping for the key, the old |
529 |
* value is replaced. |
530 |
* |
531 |
* @param key key with which the specified value is to be associated |
532 |
* @param value value to be associated with the specified key |
533 |
* |
534 |
* @return the previous value associated with <tt>key</tt>, or |
535 |
* <tt>null</tt> if there was no mapping for <tt>key</tt>. |
536 |
* (A <tt>null</tt> return can also indicate that the map |
537 |
* previously associated <tt>null</tt> with <tt>key</tt>.) |
538 |
* @throws ClassCastException if the specified key cannot be compared |
539 |
* with the keys currently in the map |
540 |
* @throws NullPointerException if the specified key is null |
541 |
* and this map uses natural ordering, or its comparator |
542 |
* does not permit null keys |
543 |
*/ |
544 |
public V put(K key, V value) { |
545 |
Entry<K,V> t = root; |
546 |
|
547 |
if (t == null) { |
548 |
// TBD |
549 |
// if (key == null) { |
550 |
// if (comparator == null) |
551 |
// throw new NullPointerException(); |
552 |
// comparator.compare(key, key); |
553 |
// } |
554 |
incrementSize(); |
555 |
root = new Entry<K,V>(key, value, null); |
556 |
return null; |
557 |
} |
558 |
|
559 |
while (true) { |
560 |
int cmp = compare(key, t.key); |
561 |
if (cmp == 0) { |
562 |
return t.setValue(value); |
563 |
} else if (cmp < 0) { |
564 |
if (t.left != null) { |
565 |
t = t.left; |
566 |
} else { |
567 |
incrementSize(); |
568 |
t.left = new Entry<K,V>(key, value, t); |
569 |
fixAfterInsertion(t.left); |
570 |
return null; |
571 |
} |
572 |
} else { // cmp > 0 |
573 |
if (t.right != null) { |
574 |
t = t.right; |
575 |
} else { |
576 |
incrementSize(); |
577 |
t.right = new Entry<K,V>(key, value, t); |
578 |
fixAfterInsertion(t.right); |
579 |
return null; |
580 |
} |
581 |
} |
582 |
} |
583 |
} |
584 |
|
585 |
/** |
586 |
* Removes the mapping for this key from this TreeMap if present. |
587 |
* |
588 |
* @param key key for which mapping should be removed |
589 |
* @return the previous value associated with <tt>key</tt>, or |
590 |
* <tt>null</tt> if there was no mapping for <tt>key</tt>. |
591 |
* (A <tt>null</tt> return can also indicate that the map |
592 |
* previously associated <tt>null</tt> with <tt>key</tt>.) |
593 |
* @throws ClassCastException if the specified key cannot be compared |
594 |
* with the keys currently in the map |
595 |
* @throws NullPointerException if the specified key is null |
596 |
* and this map uses natural ordering, or its comparator |
597 |
* does not permit null keys |
598 |
*/ |
599 |
public V remove(Object key) { |
600 |
Entry<K,V> p = getEntry(key); |
601 |
if (p == null) |
602 |
return null; |
603 |
|
604 |
V oldValue = p.value; |
605 |
deleteEntry(p); |
606 |
return oldValue; |
607 |
} |
608 |
|
609 |
/** |
610 |
* Removes all of the mappings from this map. |
611 |
* The map will be empty after this call returns. |
612 |
*/ |
613 |
public void clear() { |
614 |
modCount++; |
615 |
size = 0; |
616 |
root = null; |
617 |
} |
618 |
|
619 |
/** |
620 |
* Returns a shallow copy of this <tt>TreeMap</tt> instance. (The keys and |
621 |
* values themselves are not cloned.) |
622 |
* |
623 |
* @return a shallow copy of this map |
624 |
*/ |
625 |
public Object clone() { |
626 |
TreeMap<K,V> clone = null; |
627 |
try { |
628 |
clone = (TreeMap<K,V>) super.clone(); |
629 |
} catch (CloneNotSupportedException e) { |
630 |
throw new InternalError(); |
631 |
} |
632 |
|
633 |
// Put clone into "virgin" state (except for comparator) |
634 |
clone.root = null; |
635 |
clone.size = 0; |
636 |
clone.modCount = 0; |
637 |
clone.entrySet = null; |
638 |
clone.descendingEntrySet = null; |
639 |
clone.descendingKeySet = null; |
640 |
|
641 |
// Initialize clone with our mappings |
642 |
try { |
643 |
clone.buildFromSorted(size, entrySet().iterator(), null, null); |
644 |
} catch (java.io.IOException cannotHappen) { |
645 |
} catch (ClassNotFoundException cannotHappen) { |
646 |
} |
647 |
|
648 |
return clone; |
649 |
} |
650 |
|
651 |
// NavigableMap API methods |
652 |
|
653 |
/** |
654 |
* @since 1.6 |
655 |
*/ |
656 |
public Map.Entry<K,V> firstEntry() { |
657 |
Entry<K,V> e = getFirstEntry(); |
658 |
return (e == null)? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
659 |
} |
660 |
|
661 |
/** |
662 |
* @since 1.6 |
663 |
*/ |
664 |
public Map.Entry<K,V> lastEntry() { |
665 |
Entry<K,V> e = getLastEntry(); |
666 |
return (e == null)? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
667 |
} |
668 |
|
669 |
/** |
670 |
* @since 1.6 |
671 |
*/ |
672 |
public Map.Entry<K,V> pollFirstEntry() { |
673 |
Entry<K,V> p = getFirstEntry(); |
674 |
if (p == null) |
675 |
return null; |
676 |
Map.Entry<K,V> result = new AbstractMap.SimpleImmutableEntry<K,V>(p); |
677 |
deleteEntry(p); |
678 |
return result; |
679 |
} |
680 |
|
681 |
/** |
682 |
* @since 1.6 |
683 |
*/ |
684 |
public Map.Entry<K,V> pollLastEntry() { |
685 |
Entry<K,V> p = getLastEntry(); |
686 |
if (p == null) |
687 |
return null; |
688 |
Map.Entry<K,V> result = new AbstractMap.SimpleImmutableEntry<K,V>(p); |
689 |
deleteEntry(p); |
690 |
return result; |
691 |
} |
692 |
|
693 |
/** |
694 |
* @throws ClassCastException {@inheritDoc} |
695 |
* @throws NullPointerException if the specified key is null |
696 |
* and this map uses natural ordering, or its comparator |
697 |
* does not permit null keys |
698 |
* @since 1.6 |
699 |
*/ |
700 |
public Map.Entry<K,V> lowerEntry(K key) { |
701 |
Entry<K,V> e = getLowerEntry(key); |
702 |
return (e == null)? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
703 |
} |
704 |
|
705 |
/** |
706 |
* @throws ClassCastException {@inheritDoc} |
707 |
* @throws NullPointerException if the specified key is null |
708 |
* and this map uses natural ordering, or its comparator |
709 |
* does not permit null keys |
710 |
* @since 1.6 |
711 |
*/ |
712 |
public K lowerKey(K key) { |
713 |
Entry<K,V> e = getLowerEntry(key); |
714 |
return (e == null)? null : e.key; |
715 |
} |
716 |
|
717 |
/** |
718 |
* @throws ClassCastException {@inheritDoc} |
719 |
* @throws NullPointerException if the specified key is null |
720 |
* and this map uses natural ordering, or its comparator |
721 |
* does not permit null keys |
722 |
* @since 1.6 |
723 |
*/ |
724 |
public Map.Entry<K,V> floorEntry(K key) { |
725 |
Entry<K,V> e = getFloorEntry(key); |
726 |
return (e == null)? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
727 |
} |
728 |
|
729 |
/** |
730 |
* @throws ClassCastException {@inheritDoc} |
731 |
* @throws NullPointerException if the specified key is null |
732 |
* and this map uses natural ordering, or its comparator |
733 |
* does not permit null keys |
734 |
* @since 1.6 |
735 |
*/ |
736 |
public K floorKey(K key) { |
737 |
Entry<K,V> e = getFloorEntry(key); |
738 |
return (e == null)? null : e.key; |
739 |
} |
740 |
|
741 |
/** |
742 |
* @throws ClassCastException {@inheritDoc} |
743 |
* @throws NullPointerException if the specified key is null |
744 |
* and this map uses natural ordering, or its comparator |
745 |
* does not permit null keys |
746 |
* @since 1.6 |
747 |
*/ |
748 |
public Map.Entry<K,V> ceilingEntry(K key) { |
749 |
Entry<K,V> e = getCeilingEntry(key); |
750 |
return (e == null)? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
751 |
} |
752 |
|
753 |
/** |
754 |
* @throws ClassCastException {@inheritDoc} |
755 |
* @throws NullPointerException if the specified key is null |
756 |
* and this map uses natural ordering, or its comparator |
757 |
* does not permit null keys |
758 |
* @since 1.6 |
759 |
*/ |
760 |
public K ceilingKey(K key) { |
761 |
Entry<K,V> e = getCeilingEntry(key); |
762 |
return (e == null)? null : e.key; |
763 |
} |
764 |
|
765 |
/** |
766 |
* @throws ClassCastException {@inheritDoc} |
767 |
* @throws NullPointerException if the specified key is null |
768 |
* and this map uses natural ordering, or its comparator |
769 |
* does not permit null keys |
770 |
* @since 1.6 |
771 |
*/ |
772 |
public Map.Entry<K,V> higherEntry(K key) { |
773 |
Entry<K,V> e = getHigherEntry(key); |
774 |
return (e == null)? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
775 |
} |
776 |
|
777 |
/** |
778 |
* @throws ClassCastException {@inheritDoc} |
779 |
* @throws NullPointerException if the specified key is null |
780 |
* and this map uses natural ordering, or its comparator |
781 |
* does not permit null keys |
782 |
* @since 1.6 |
783 |
*/ |
784 |
public K higherKey(K key) { |
785 |
Entry<K,V> e = getHigherEntry(key); |
786 |
return (e == null)? null : e.key; |
787 |
} |
788 |
|
789 |
// Views |
790 |
|
791 |
/** |
792 |
* Fields initialized to contain an instance of the entry set view |
793 |
* the first time this view is requested. Views are stateless, so |
794 |
* there's no reason to create more than one. |
795 |
*/ |
796 |
private transient Set<Map.Entry<K,V>> entrySet = null; |
797 |
private transient Set<Map.Entry<K,V>> descendingEntrySet = null; |
798 |
private transient Set<K> descendingKeySet = null; |
799 |
|
800 |
/** |
801 |
* Returns a {@link Set} view of the keys contained in this map. |
802 |
* The set's iterator returns the keys in ascending order. |
803 |
* The set is backed by the map, so changes to the map are |
804 |
* reflected in the set, and vice-versa. If the map is modified |
805 |
* while an iteration over the set is in progress (except through |
806 |
* the iterator's own <tt>remove</tt> operation), the results of |
807 |
* the iteration are undefined. The set supports element removal, |
808 |
* which removes the corresponding mapping from the map, via the |
809 |
* <tt>Iterator.remove</tt>, <tt>Set.remove</tt>, |
810 |
* <tt>removeAll</tt>, <tt>retainAll</tt>, and <tt>clear</tt> |
811 |
* operations. It does not support the <tt>add</tt> or <tt>addAll</tt> |
812 |
* operations. |
813 |
*/ |
814 |
public Set<K> keySet() { |
815 |
Set<K> ks = keySet; |
816 |
return (ks != null) ? ks : (keySet = new KeySet()); |
817 |
} |
818 |
|
819 |
class KeySet extends AbstractSet<K> { |
820 |
public Iterator<K> iterator() { |
821 |
return new KeyIterator(getFirstEntry()); |
822 |
} |
823 |
|
824 |
public int size() { |
825 |
return TreeMap.this.size(); |
826 |
} |
827 |
|
828 |
public boolean contains(Object o) { |
829 |
return containsKey(o); |
830 |
} |
831 |
|
832 |
public boolean remove(Object o) { |
833 |
int oldSize = size; |
834 |
TreeMap.this.remove(o); |
835 |
return size != oldSize; |
836 |
} |
837 |
|
838 |
public void clear() { |
839 |
TreeMap.this.clear(); |
840 |
} |
841 |
} |
842 |
|
843 |
/** |
844 |
* Returns a {@link Collection} view of the values contained in this map. |
845 |
* The collection's iterator returns the values in ascending order |
846 |
* of the corresponding keys. |
847 |
* The collection is backed by the map, so changes to the map are |
848 |
* reflected in the collection, and vice-versa. If the map is |
849 |
* modified while an iteration over the collection is in progress |
850 |
* (except through the iterator's own <tt>remove</tt> operation), |
851 |
* the results of the iteration are undefined. The collection |
852 |
* supports element removal, which removes the corresponding |
853 |
* mapping from the map, via the <tt>Iterator.remove</tt>, |
854 |
* <tt>Collection.remove</tt>, <tt>removeAll</tt>, |
855 |
* <tt>retainAll</tt> and <tt>clear</tt> operations. It does not |
856 |
* support the <tt>add</tt> or <tt>addAll</tt> operations. |
857 |
*/ |
858 |
public Collection<V> values() { |
859 |
Collection<V> vs = values; |
860 |
return (vs != null) ? vs : (values = new Values()); |
861 |
} |
862 |
|
863 |
class Values extends AbstractCollection<V> { |
864 |
public Iterator<V> iterator() { |
865 |
return new ValueIterator(getFirstEntry()); |
866 |
} |
867 |
|
868 |
public int size() { |
869 |
return TreeMap.this.size(); |
870 |
} |
871 |
|
872 |
public boolean contains(Object o) { |
873 |
for (Entry<K,V> e = getFirstEntry(); e != null; e = successor(e)) |
874 |
if (valEquals(e.getValue(), o)) |
875 |
return true; |
876 |
return false; |
877 |
} |
878 |
|
879 |
public boolean remove(Object o) { |
880 |
for (Entry<K,V> e = getFirstEntry(); e != null; e = successor(e)) { |
881 |
if (valEquals(e.getValue(), o)) { |
882 |
deleteEntry(e); |
883 |
return true; |
884 |
} |
885 |
} |
886 |
return false; |
887 |
} |
888 |
|
889 |
public void clear() { |
890 |
TreeMap.this.clear(); |
891 |
} |
892 |
} |
893 |
|
894 |
/** |
895 |
* Returns a {@link Set} view of the mappings contained in this map. |
896 |
* The set's iterator returns the entries in ascending key order. |
897 |
* The set is backed by the map, so changes to the map are |
898 |
* reflected in the set, and vice-versa. If the map is modified |
899 |
* while an iteration over the set is in progress (except through |
900 |
* the iterator's own <tt>remove</tt> operation, or through the |
901 |
* <tt>setValue</tt> operation on a map entry returned by the |
902 |
* iterator) the results of the iteration are undefined. The set |
903 |
* supports element removal, which removes the corresponding |
904 |
* mapping from the map, via the <tt>Iterator.remove</tt>, |
905 |
* <tt>Set.remove</tt>, <tt>removeAll</tt>, <tt>retainAll</tt> and |
906 |
* <tt>clear</tt> operations. It does not support the |
907 |
* <tt>add</tt> or <tt>addAll</tt> operations. |
908 |
*/ |
909 |
public Set<Map.Entry<K,V>> entrySet() { |
910 |
Set<Map.Entry<K,V>> es = entrySet; |
911 |
return (es != null) ? es : (entrySet = new EntrySet()); |
912 |
} |
913 |
|
914 |
class EntrySet extends AbstractSet<Map.Entry<K,V>> { |
915 |
public Iterator<Map.Entry<K,V>> iterator() { |
916 |
return new EntryIterator(getFirstEntry()); |
917 |
} |
918 |
|
919 |
public boolean contains(Object o) { |
920 |
if (!(o instanceof Map.Entry)) |
921 |
return false; |
922 |
Map.Entry<K,V> entry = (Map.Entry<K,V>) o; |
923 |
V value = entry.getValue(); |
924 |
Entry<K,V> p = getEntry(entry.getKey()); |
925 |
return p != null && valEquals(p.getValue(), value); |
926 |
} |
927 |
|
928 |
public boolean remove(Object o) { |
929 |
if (!(o instanceof Map.Entry)) |
930 |
return false; |
931 |
Map.Entry<K,V> entry = (Map.Entry<K,V>) o; |
932 |
V value = entry.getValue(); |
933 |
Entry<K,V> p = getEntry(entry.getKey()); |
934 |
if (p != null && valEquals(p.getValue(), value)) { |
935 |
deleteEntry(p); |
936 |
return true; |
937 |
} |
938 |
return false; |
939 |
} |
940 |
|
941 |
public int size() { |
942 |
return TreeMap.this.size(); |
943 |
} |
944 |
|
945 |
public void clear() { |
946 |
TreeMap.this.clear(); |
947 |
} |
948 |
} |
949 |
|
950 |
/** |
951 |
* @since 1.6 |
952 |
*/ |
953 |
public Set<Map.Entry<K,V>> descendingEntrySet() { |
954 |
Set<Map.Entry<K,V>> es = descendingEntrySet; |
955 |
return (es != null) ? es : (descendingEntrySet = new DescendingEntrySet()); |
956 |
} |
957 |
|
958 |
class DescendingEntrySet extends EntrySet { |
959 |
public Iterator<Map.Entry<K,V>> iterator() { |
960 |
return new DescendingEntryIterator(getLastEntry()); |
961 |
} |
962 |
} |
963 |
|
964 |
/** |
965 |
* @since 1.6 |
966 |
*/ |
967 |
public Set<K> descendingKeySet() { |
968 |
Set<K> ks = descendingKeySet; |
969 |
return (ks != null) ? ks : (descendingKeySet = new DescendingKeySet()); |
970 |
} |
971 |
|
972 |
class DescendingKeySet extends KeySet { |
973 |
public Iterator<K> iterator() { |
974 |
return new DescendingKeyIterator(getLastEntry()); |
975 |
} |
976 |
} |
977 |
|
978 |
/** |
979 |
* @throws ClassCastException {@inheritDoc} |
980 |
* @throws NullPointerException if <tt>fromKey</tt> or <tt>toKey</tt> is |
981 |
* null and this map uses natural ordering, or its comparator |
982 |
* does not permit null keys |
983 |
* @throws IllegalArgumentException {@inheritDoc} |
984 |
* @since 1.6 |
985 |
*/ |
986 |
public NavigableMap<K,V> navigableSubMap(K fromKey, K toKey) { |
987 |
return new SubMap(fromKey, toKey); |
988 |
} |
989 |
|
990 |
/** |
991 |
* @throws ClassCastException {@inheritDoc} |
992 |
* @throws NullPointerException if <tt>toKey</tt> is null |
993 |
* and this map uses natural ordering, or its comparator |
994 |
* does not permit null keys |
995 |
* @throws IllegalArgumentException {@inheritDoc} |
996 |
* @since 1.6 |
997 |
*/ |
998 |
public NavigableMap<K,V> navigableHeadMap(K toKey) { |
999 |
return new SubMap(toKey, true); |
1000 |
} |
1001 |
|
1002 |
/** |
1003 |
* @throws ClassCastException {@inheritDoc} |
1004 |
* @throws NullPointerException if <tt>fromKey</tt> is null |
1005 |
* and this map uses natural ordering, or its comparator |
1006 |
* does not permit null keys |
1007 |
* @throws IllegalArgumentException {@inheritDoc} |
1008 |
* @since 1.6 |
1009 |
*/ |
1010 |
public NavigableMap<K,V> navigableTailMap(K fromKey) { |
1011 |
return new SubMap(fromKey, false); |
1012 |
} |
1013 |
|
1014 |
/** |
1015 |
* Equivalent to {@link #navigableSubMap} but with a return type |
1016 |
* conforming to the <tt>SortedMap</tt> interface. |
1017 |
* |
1018 |
* <p>{@inheritDoc} |
1019 |
* |
1020 |
* @throws ClassCastException {@inheritDoc} |
1021 |
* @throws NullPointerException if <tt>fromKey</tt> or <tt>toKey</tt> is |
1022 |
* null and this map uses natural ordering, or its comparator |
1023 |
* does not permit null keys |
1024 |
* @throws IllegalArgumentException {@inheritDoc} |
1025 |
*/ |
1026 |
public SortedMap<K,V> subMap(K fromKey, K toKey) { |
1027 |
return new SubMap(fromKey, toKey); |
1028 |
} |
1029 |
|
1030 |
/** |
1031 |
* Equivalent to {@link #navigableHeadMap} but with a return type |
1032 |
* conforming to the <tt>SortedMap</tt> interface. |
1033 |
* |
1034 |
* <p>{@inheritDoc} |
1035 |
* |
1036 |
* @throws ClassCastException {@inheritDoc} |
1037 |
* @throws NullPointerException if <tt>toKey</tt> is null |
1038 |
* and this map uses natural ordering, or its comparator |
1039 |
* does not permit null keys |
1040 |
* @throws IllegalArgumentException {@inheritDoc} |
1041 |
*/ |
1042 |
public SortedMap<K,V> headMap(K toKey) { |
1043 |
return new SubMap(toKey, true); |
1044 |
} |
1045 |
|
1046 |
/** |
1047 |
* Equivalent to {@link #navigableTailMap} but with a return type |
1048 |
* conforming to the <tt>SortedMap</tt> interface. |
1049 |
* |
1050 |
* <p>{@inheritDoc} |
1051 |
* |
1052 |
* @throws ClassCastException {@inheritDoc} |
1053 |
* @throws NullPointerException if <tt>fromKey</tt> is null |
1054 |
* and this map uses natural ordering, or its comparator |
1055 |
* does not permit null keys |
1056 |
* @throws IllegalArgumentException {@inheritDoc} |
1057 |
*/ |
1058 |
public SortedMap<K,V> tailMap(K fromKey) { |
1059 |
return new SubMap(fromKey, false); |
1060 |
} |
1061 |
|
1062 |
private class SubMap |
1063 |
extends AbstractMap<K,V> |
1064 |
implements NavigableMap<K,V>, java.io.Serializable { |
1065 |
private static final long serialVersionUID = -6520786458950516097L; |
1066 |
|
1067 |
/** |
1068 |
* fromKey is significant only if fromStart is false. Similarly, |
1069 |
* toKey is significant only if toStart is false. |
1070 |
*/ |
1071 |
private boolean fromStart = false, toEnd = false; |
1072 |
private K fromKey, toKey; |
1073 |
|
1074 |
SubMap(K fromKey, K toKey) { |
1075 |
if (compare(fromKey, toKey) > 0) |
1076 |
throw new IllegalArgumentException("fromKey > toKey"); |
1077 |
this.fromKey = fromKey; |
1078 |
this.toKey = toKey; |
1079 |
} |
1080 |
|
1081 |
SubMap(K key, boolean headMap) { |
1082 |
compare(key, key); // Type-check key |
1083 |
|
1084 |
if (headMap) { |
1085 |
fromStart = true; |
1086 |
toKey = key; |
1087 |
} else { |
1088 |
toEnd = true; |
1089 |
fromKey = key; |
1090 |
} |
1091 |
} |
1092 |
|
1093 |
SubMap(boolean fromStart, K fromKey, boolean toEnd, K toKey) { |
1094 |
this.fromStart = fromStart; |
1095 |
this.fromKey= fromKey; |
1096 |
this.toEnd = toEnd; |
1097 |
this.toKey = toKey; |
1098 |
} |
1099 |
|
1100 |
public boolean isEmpty() { |
1101 |
return entrySet().isEmpty(); |
1102 |
} |
1103 |
|
1104 |
public boolean containsKey(Object key) { |
1105 |
return inRange(key) && TreeMap.this.containsKey(key); |
1106 |
} |
1107 |
|
1108 |
public V get(Object key) { |
1109 |
if (!inRange(key)) |
1110 |
return null; |
1111 |
return TreeMap.this.get(key); |
1112 |
} |
1113 |
|
1114 |
public V put(K key, V value) { |
1115 |
if (!inRange(key)) |
1116 |
throw new IllegalArgumentException("key out of range"); |
1117 |
return TreeMap.this.put(key, value); |
1118 |
} |
1119 |
|
1120 |
public V remove(Object key) { |
1121 |
if (!inRange(key)) |
1122 |
return null; |
1123 |
return TreeMap.this.remove(key); |
1124 |
} |
1125 |
|
1126 |
public Comparator<? super K> comparator() { |
1127 |
return comparator; |
1128 |
} |
1129 |
|
1130 |
public K firstKey() { |
1131 |
TreeMap.Entry<K,V> e = fromStart ? getFirstEntry() : getCeilingEntry(fromKey); |
1132 |
K first = key(e); |
1133 |
if (!toEnd && compare(first, toKey) >= 0) |
1134 |
throw new NoSuchElementException(); |
1135 |
return first; |
1136 |
} |
1137 |
|
1138 |
public K lastKey() { |
1139 |
TreeMap.Entry<K,V> e = toEnd ? getLastEntry() : getLowerEntry(toKey); |
1140 |
K last = key(e); |
1141 |
if (!fromStart && compare(last, fromKey) < 0) |
1142 |
throw new NoSuchElementException(); |
1143 |
return last; |
1144 |
} |
1145 |
|
1146 |
public Map.Entry<K,V> firstEntry() { |
1147 |
TreeMap.Entry<K,V> e = fromStart ? |
1148 |
getFirstEntry() : getCeilingEntry(fromKey); |
1149 |
if (e == null || (!toEnd && compare(e.key, toKey) >= 0)) |
1150 |
return null; |
1151 |
return e; |
1152 |
} |
1153 |
|
1154 |
public Map.Entry<K,V> lastEntry() { |
1155 |
TreeMap.Entry<K,V> e = toEnd ? |
1156 |
getLastEntry() : getLowerEntry(toKey); |
1157 |
if (e == null || (!fromStart && compare(e.key, fromKey) < 0)) |
1158 |
return null; |
1159 |
return e; |
1160 |
} |
1161 |
|
1162 |
public Map.Entry<K,V> pollFirstEntry() { |
1163 |
TreeMap.Entry<K,V> e = fromStart ? |
1164 |
getFirstEntry() : getCeilingEntry(fromKey); |
1165 |
if (e == null || (!toEnd && compare(e.key, toKey) >= 0)) |
1166 |
return null; |
1167 |
Map.Entry<K,V> result = new AbstractMap.SimpleImmutableEntry<K,V>(e); |
1168 |
deleteEntry(e); |
1169 |
return result; |
1170 |
} |
1171 |
|
1172 |
public Map.Entry<K,V> pollLastEntry() { |
1173 |
TreeMap.Entry<K,V> e = toEnd ? |
1174 |
getLastEntry() : getLowerEntry(toKey); |
1175 |
if (e == null || (!fromStart && compare(e.key, fromKey) < 0)) |
1176 |
return null; |
1177 |
Map.Entry<K,V> result = new AbstractMap.SimpleImmutableEntry<K,V>(e); |
1178 |
deleteEntry(e); |
1179 |
return result; |
1180 |
} |
1181 |
|
1182 |
private TreeMap.Entry<K,V> subceiling(K key) { |
1183 |
TreeMap.Entry<K,V> e = (!fromStart && compare(key, fromKey) < 0)? |
1184 |
getCeilingEntry(fromKey) : getCeilingEntry(key); |
1185 |
if (e == null || (!toEnd && compare(e.key, toKey) >= 0)) |
1186 |
return null; |
1187 |
return e; |
1188 |
} |
1189 |
|
1190 |
public Map.Entry<K,V> ceilingEntry(K key) { |
1191 |
TreeMap.Entry<K,V> e = subceiling(key); |
1192 |
return e == null? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
1193 |
} |
1194 |
|
1195 |
public K ceilingKey(K key) { |
1196 |
TreeMap.Entry<K,V> e = subceiling(key); |
1197 |
return e == null? null : e.key; |
1198 |
} |
1199 |
|
1200 |
|
1201 |
private TreeMap.Entry<K,V> subhigher(K key) { |
1202 |
TreeMap.Entry<K,V> e = (!fromStart && compare(key, fromKey) < 0)? |
1203 |
getCeilingEntry(fromKey) : getHigherEntry(key); |
1204 |
if (e == null || (!toEnd && compare(e.key, toKey) >= 0)) |
1205 |
return null; |
1206 |
return e; |
1207 |
} |
1208 |
|
1209 |
public Map.Entry<K,V> higherEntry(K key) { |
1210 |
TreeMap.Entry<K,V> e = subhigher(key); |
1211 |
return e == null? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
1212 |
} |
1213 |
|
1214 |
public K higherKey(K key) { |
1215 |
TreeMap.Entry<K,V> e = subhigher(key); |
1216 |
return e == null? null : e.key; |
1217 |
} |
1218 |
|
1219 |
private TreeMap.Entry<K,V> subfloor(K key) { |
1220 |
TreeMap.Entry<K,V> e = (!toEnd && compare(key, toKey) >= 0)? |
1221 |
getLowerEntry(toKey) : getFloorEntry(key); |
1222 |
if (e == null || (!fromStart && compare(e.key, fromKey) < 0)) |
1223 |
return null; |
1224 |
return e; |
1225 |
} |
1226 |
|
1227 |
public Map.Entry<K,V> floorEntry(K key) { |
1228 |
TreeMap.Entry<K,V> e = subfloor(key); |
1229 |
return e == null? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
1230 |
} |
1231 |
|
1232 |
public K floorKey(K key) { |
1233 |
TreeMap.Entry<K,V> e = subfloor(key); |
1234 |
return e == null? null : e.key; |
1235 |
} |
1236 |
|
1237 |
private TreeMap.Entry<K,V> sublower(K key) { |
1238 |
TreeMap.Entry<K,V> e = (!toEnd && compare(key, toKey) >= 0)? |
1239 |
getLowerEntry(toKey) : getLowerEntry(key); |
1240 |
if (e == null || (!fromStart && compare(e.key, fromKey) < 0)) |
1241 |
return null; |
1242 |
return e; |
1243 |
} |
1244 |
|
1245 |
public Map.Entry<K,V> lowerEntry(K key) { |
1246 |
TreeMap.Entry<K,V> e = sublower(key); |
1247 |
return e == null? null : new AbstractMap.SimpleImmutableEntry<K,V>(e); |
1248 |
} |
1249 |
|
1250 |
public K lowerKey(K key) { |
1251 |
TreeMap.Entry<K,V> e = sublower(key); |
1252 |
return e == null? null : e.key; |
1253 |
} |
1254 |
|
1255 |
private transient Set<Map.Entry<K,V>> entrySet = null; |
1256 |
|
1257 |
public Set<Map.Entry<K,V>> entrySet() { |
1258 |
Set<Map.Entry<K,V>> es = entrySet; |
1259 |
return (es != null)? es : (entrySet = new EntrySetView()); |
1260 |
} |
1261 |
|
1262 |
private class EntrySetView extends AbstractSet<Map.Entry<K,V>> { |
1263 |
private transient int size = -1, sizeModCount; |
1264 |
|
1265 |
public int size() { |
1266 |
if (size == -1 || sizeModCount != TreeMap.this.modCount) { |
1267 |
size = 0; sizeModCount = TreeMap.this.modCount; |
1268 |
Iterator i = iterator(); |
1269 |
while (i.hasNext()) { |
1270 |
size++; |
1271 |
i.next(); |
1272 |
} |
1273 |
} |
1274 |
return size; |
1275 |
} |
1276 |
|
1277 |
public boolean isEmpty() { |
1278 |
return !iterator().hasNext(); |
1279 |
} |
1280 |
|
1281 |
public boolean contains(Object o) { |
1282 |
if (!(o instanceof Map.Entry)) |
1283 |
return false; |
1284 |
Map.Entry<K,V> entry = (Map.Entry<K,V>) o; |
1285 |
K key = entry.getKey(); |
1286 |
if (!inRange(key)) |
1287 |
return false; |
1288 |
TreeMap.Entry node = getEntry(key); |
1289 |
return node != null && |
1290 |
valEquals(node.getValue(), entry.getValue()); |
1291 |
} |
1292 |
|
1293 |
public boolean remove(Object o) { |
1294 |
if (!(o instanceof Map.Entry)) |
1295 |
return false; |
1296 |
Map.Entry<K,V> entry = (Map.Entry<K,V>) o; |
1297 |
K key = entry.getKey(); |
1298 |
if (!inRange(key)) |
1299 |
return false; |
1300 |
TreeMap.Entry<K,V> node = getEntry(key); |
1301 |
if (node!=null && valEquals(node.getValue(),entry.getValue())){ |
1302 |
deleteEntry(node); |
1303 |
return true; |
1304 |
} |
1305 |
return false; |
1306 |
} |
1307 |
|
1308 |
public Iterator<Map.Entry<K,V>> iterator() { |
1309 |
return new SubMapEntryIterator( |
1310 |
(fromStart ? getFirstEntry() : getCeilingEntry(fromKey)), |
1311 |
(toEnd ? null : getCeilingEntry(toKey))); |
1312 |
} |
1313 |
} |
1314 |
|
1315 |
private transient Set<Map.Entry<K,V>> descendingEntrySetView = null; |
1316 |
private transient Set<K> descendingKeySetView = null; |
1317 |
|
1318 |
public Set<Map.Entry<K,V>> descendingEntrySet() { |
1319 |
Set<Map.Entry<K,V>> es = descendingEntrySetView; |
1320 |
return (es != null) ? es : |
1321 |
(descendingEntrySetView = new DescendingEntrySetView()); |
1322 |
} |
1323 |
|
1324 |
public Set<K> descendingKeySet() { |
1325 |
Set<K> ks = descendingKeySetView; |
1326 |
return (ks != null) ? ks : |
1327 |
(descendingKeySetView = new DescendingKeySetView()); |
1328 |
} |
1329 |
|
1330 |
private class DescendingEntrySetView extends EntrySetView { |
1331 |
public Iterator<Map.Entry<K,V>> iterator() { |
1332 |
return new DescendingSubMapEntryIterator |
1333 |
((toEnd ? getLastEntry() : getLowerEntry(toKey)), |
1334 |
(fromStart ? null : getLowerEntry(fromKey))); |
1335 |
} |
1336 |
} |
1337 |
|
1338 |
private class DescendingKeySetView extends AbstractSet<K> { |
1339 |
public Iterator<K> iterator() { |
1340 |
return new Iterator<K>() { |
1341 |
private Iterator<Entry<K,V>> i = descendingEntrySet().iterator(); |
1342 |
|
1343 |
public boolean hasNext() { return i.hasNext(); } |
1344 |
public K next() { return i.next().getKey(); } |
1345 |
public void remove() { i.remove(); } |
1346 |
}; |
1347 |
} |
1348 |
|
1349 |
public int size() { |
1350 |
return SubMap.this.size(); |
1351 |
} |
1352 |
|
1353 |
public boolean contains(Object k) { |
1354 |
return SubMap.this.containsKey(k); |
1355 |
} |
1356 |
} |
1357 |
|
1358 |
public NavigableMap<K,V> navigableSubMap(K fromKey, K toKey) { |
1359 |
if (!inRange2(fromKey)) |
1360 |
throw new IllegalArgumentException("fromKey out of range"); |
1361 |
if (!inRange2(toKey)) |
1362 |
throw new IllegalArgumentException("toKey out of range"); |
1363 |
return new SubMap(fromKey, toKey); |
1364 |
} |
1365 |
|
1366 |
public NavigableMap<K,V> navigableHeadMap(K toKey) { |
1367 |
if (!inRange2(toKey)) |
1368 |
throw new IllegalArgumentException("toKey out of range"); |
1369 |
return new SubMap(fromStart, fromKey, false, toKey); |
1370 |
} |
1371 |
|
1372 |
public NavigableMap<K,V> navigableTailMap(K fromKey) { |
1373 |
if (!inRange2(fromKey)) |
1374 |
throw new IllegalArgumentException("fromKey out of range"); |
1375 |
return new SubMap(false, fromKey, toEnd, toKey); |
1376 |
} |
1377 |
|
1378 |
public SortedMap<K,V> subMap(K fromKey, K toKey) { |
1379 |
return navigableSubMap(fromKey, toKey); |
1380 |
} |
1381 |
|
1382 |
public SortedMap<K,V> headMap(K toKey) { |
1383 |
return navigableHeadMap(toKey); |
1384 |
} |
1385 |
|
1386 |
public SortedMap<K,V> tailMap(K fromKey) { |
1387 |
return navigableTailMap(fromKey); |
1388 |
} |
1389 |
|
1390 |
private boolean inRange(Object key) { |
1391 |
return (fromStart || compare(key, fromKey) >= 0) && |
1392 |
(toEnd || compare(key, toKey) < 0); |
1393 |
} |
1394 |
|
1395 |
// This form allows the high endpoint (as well as all legit keys) |
1396 |
private boolean inRange2(Object key) { |
1397 |
return (fromStart || compare(key, fromKey) >= 0) && |
1398 |
(toEnd || compare(key, toKey) <= 0); |
1399 |
} |
1400 |
} |
1401 |
|
1402 |
/** |
1403 |
* TreeMap Iterator. |
1404 |
*/ |
1405 |
abstract class PrivateEntryIterator<T> implements Iterator<T> { |
1406 |
int expectedModCount = TreeMap.this.modCount; |
1407 |
Entry<K,V> lastReturned = null; |
1408 |
Entry<K,V> next; |
1409 |
|
1410 |
PrivateEntryIterator(Entry<K,V> first) { |
1411 |
next = first; |
1412 |
} |
1413 |
|
1414 |
public boolean hasNext() { |
1415 |
return next != null; |
1416 |
} |
1417 |
|
1418 |
Entry<K,V> nextEntry() { |
1419 |
if (next == null) |
1420 |
throw new NoSuchElementException(); |
1421 |
if (modCount != expectedModCount) |
1422 |
throw new ConcurrentModificationException(); |
1423 |
lastReturned = next; |
1424 |
next = successor(next); |
1425 |
return lastReturned; |
1426 |
} |
1427 |
|
1428 |
public void remove() { |
1429 |
if (lastReturned == null) |
1430 |
throw new IllegalStateException(); |
1431 |
if (modCount != expectedModCount) |
1432 |
throw new ConcurrentModificationException(); |
1433 |
if (lastReturned.left != null && lastReturned.right != null) |
1434 |
next = lastReturned; |
1435 |
deleteEntry(lastReturned); |
1436 |
expectedModCount++; |
1437 |
lastReturned = null; |
1438 |
} |
1439 |
} |
1440 |
|
1441 |
class EntryIterator extends PrivateEntryIterator<Map.Entry<K,V>> { |
1442 |
EntryIterator(Entry<K,V> first) { |
1443 |
super(first); |
1444 |
} |
1445 |
public Map.Entry<K,V> next() { |
1446 |
return nextEntry(); |
1447 |
} |
1448 |
} |
1449 |
|
1450 |
class KeyIterator extends PrivateEntryIterator<K> { |
1451 |
KeyIterator(Entry<K,V> first) { |
1452 |
super(first); |
1453 |
} |
1454 |
public K next() { |
1455 |
return nextEntry().key; |
1456 |
} |
1457 |
} |
1458 |
|
1459 |
class ValueIterator extends PrivateEntryIterator<V> { |
1460 |
ValueIterator(Entry<K,V> first) { |
1461 |
super(first); |
1462 |
} |
1463 |
public V next() { |
1464 |
return nextEntry().value; |
1465 |
} |
1466 |
} |
1467 |
|
1468 |
class SubMapEntryIterator extends PrivateEntryIterator<Map.Entry<K,V>> { |
1469 |
private final K firstExcludedKey; |
1470 |
|
1471 |
SubMapEntryIterator(Entry<K,V> first, Entry<K,V> firstExcluded) { |
1472 |
super(first); |
1473 |
firstExcludedKey = (firstExcluded == null |
1474 |
? null |
1475 |
: firstExcluded.key); |
1476 |
} |
1477 |
|
1478 |
public boolean hasNext() { |
1479 |
return next != null && next.key != firstExcludedKey; |
1480 |
} |
1481 |
|
1482 |
public Map.Entry<K,V> next() { |
1483 |
if (next == null || next.key == firstExcludedKey) |
1484 |
throw new NoSuchElementException(); |
1485 |
return nextEntry(); |
1486 |
} |
1487 |
} |
1488 |
|
1489 |
/** |
1490 |
* Base for Descending Iterators. |
1491 |
*/ |
1492 |
abstract class DescendingPrivateEntryIterator<T> extends PrivateEntryIterator<T> { |
1493 |
DescendingPrivateEntryIterator(Entry<K,V> first) { |
1494 |
super(first); |
1495 |
} |
1496 |
|
1497 |
Entry<K,V> nextEntry() { |
1498 |
if (next == null) |
1499 |
throw new NoSuchElementException(); |
1500 |
if (modCount != expectedModCount) |
1501 |
throw new ConcurrentModificationException(); |
1502 |
lastReturned = next; |
1503 |
next = predecessor(next); |
1504 |
return lastReturned; |
1505 |
} |
1506 |
} |
1507 |
|
1508 |
class DescendingEntryIterator extends DescendingPrivateEntryIterator<Map.Entry<K,V>> { |
1509 |
DescendingEntryIterator(Entry<K,V> first) { |
1510 |
super(first); |
1511 |
} |
1512 |
public Map.Entry<K,V> next() { |
1513 |
return nextEntry(); |
1514 |
} |
1515 |
} |
1516 |
|
1517 |
class DescendingKeyIterator extends DescendingPrivateEntryIterator<K> { |
1518 |
DescendingKeyIterator(Entry<K,V> first) { |
1519 |
super(first); |
1520 |
} |
1521 |
public K next() { |
1522 |
return nextEntry().key; |
1523 |
} |
1524 |
} |
1525 |
|
1526 |
|
1527 |
class DescendingSubMapEntryIterator extends DescendingPrivateEntryIterator<Map.Entry<K,V>> { |
1528 |
private final K lastExcludedKey; |
1529 |
|
1530 |
DescendingSubMapEntryIterator(Entry<K,V> last, Entry<K,V> lastExcluded) { |
1531 |
super(last); |
1532 |
lastExcludedKey = (lastExcluded == null |
1533 |
? null |
1534 |
: lastExcluded.key); |
1535 |
} |
1536 |
|
1537 |
public boolean hasNext() { |
1538 |
return next != null && next.key != lastExcludedKey; |
1539 |
} |
1540 |
|
1541 |
public Map.Entry<K,V> next() { |
1542 |
if (next == null || next.key == lastExcludedKey) |
1543 |
throw new NoSuchElementException(); |
1544 |
return nextEntry(); |
1545 |
} |
1546 |
|
1547 |
} |
1548 |
|
1549 |
/** |
1550 |
* Compares two keys using the correct comparison method for this TreeMap. |
1551 |
*/ |
1552 |
private int compare(Object k1, Object k2) { |
1553 |
return comparator==null ? ((Comparable<? super K>)k1).compareTo((K)k2) |
1554 |
: comparator.compare((K)k1, (K)k2); |
1555 |
} |
1556 |
|
1557 |
/** |
1558 |
* Test two values for equality. Differs from o1.equals(o2) only in |
1559 |
* that it copes with <tt>null</tt> o1 properly. |
1560 |
*/ |
1561 |
private static boolean valEquals(Object o1, Object o2) { |
1562 |
return (o1==null ? o2==null : o1.equals(o2)); |
1563 |
} |
1564 |
|
1565 |
private static final boolean RED = false; |
1566 |
private static final boolean BLACK = true; |
1567 |
|
1568 |
/** |
1569 |
* Node in the Tree. Doubles as a means to pass key-value pairs back to |
1570 |
* user (see Map.Entry). |
1571 |
*/ |
1572 |
|
1573 |
static class Entry<K,V> implements Map.Entry<K,V> { |
1574 |
K key; |
1575 |
V value; |
1576 |
Entry<K,V> left = null; |
1577 |
Entry<K,V> right = null; |
1578 |
Entry<K,V> parent; |
1579 |
boolean color = BLACK; |
1580 |
|
1581 |
/** |
1582 |
* Make a new cell with given key, value, and parent, and with |
1583 |
* <tt>null</tt> child links, and BLACK color. |
1584 |
*/ |
1585 |
Entry(K key, V value, Entry<K,V> parent) { |
1586 |
this.key = key; |
1587 |
this.value = value; |
1588 |
this.parent = parent; |
1589 |
} |
1590 |
|
1591 |
/** |
1592 |
* Returns the key. |
1593 |
* |
1594 |
* @return the key |
1595 |
*/ |
1596 |
public K getKey() { |
1597 |
return key; |
1598 |
} |
1599 |
|
1600 |
/** |
1601 |
* Returns the value associated with the key. |
1602 |
* |
1603 |
* @return the value associated with the key |
1604 |
*/ |
1605 |
public V getValue() { |
1606 |
return value; |
1607 |
} |
1608 |
|
1609 |
/** |
1610 |
* Replaces the value currently associated with the key with the given |
1611 |
* value. |
1612 |
* |
1613 |
* @return the value associated with the key before this method was |
1614 |
* called |
1615 |
*/ |
1616 |
public V setValue(V value) { |
1617 |
V oldValue = this.value; |
1618 |
this.value = value; |
1619 |
return oldValue; |
1620 |
} |
1621 |
|
1622 |
public boolean equals(Object o) { |
1623 |
if (!(o instanceof Map.Entry)) |
1624 |
return false; |
1625 |
Map.Entry e = (Map.Entry)o; |
1626 |
|
1627 |
return valEquals(key,e.getKey()) && valEquals(value,e.getValue()); |
1628 |
} |
1629 |
|
1630 |
public int hashCode() { |
1631 |
int keyHash = (key==null ? 0 : key.hashCode()); |
1632 |
int valueHash = (value==null ? 0 : value.hashCode()); |
1633 |
return keyHash ^ valueHash; |
1634 |
} |
1635 |
|
1636 |
public String toString() { |
1637 |
return key + "=" + value; |
1638 |
} |
1639 |
} |
1640 |
|
1641 |
/** |
1642 |
* Returns the first Entry in the TreeMap (according to the TreeMap's |
1643 |
* key-sort function). Returns null if the TreeMap is empty. |
1644 |
*/ |
1645 |
private Entry<K,V> getFirstEntry() { |
1646 |
Entry<K,V> p = root; |
1647 |
if (p != null) |
1648 |
while (p.left != null) |
1649 |
p = p.left; |
1650 |
return p; |
1651 |
} |
1652 |
|
1653 |
/** |
1654 |
* Returns the last Entry in the TreeMap (according to the TreeMap's |
1655 |
* key-sort function). Returns null if the TreeMap is empty. |
1656 |
*/ |
1657 |
private Entry<K,V> getLastEntry() { |
1658 |
Entry<K,V> p = root; |
1659 |
if (p != null) |
1660 |
while (p.right != null) |
1661 |
p = p.right; |
1662 |
return p; |
1663 |
} |
1664 |
|
1665 |
/** |
1666 |
* Returns the successor of the specified Entry, or null if no such. |
1667 |
*/ |
1668 |
private Entry<K,V> successor(Entry<K,V> t) { |
1669 |
if (t == null) |
1670 |
return null; |
1671 |
else if (t.right != null) { |
1672 |
Entry<K,V> p = t.right; |
1673 |
while (p.left != null) |
1674 |
p = p.left; |
1675 |
return p; |
1676 |
} else { |
1677 |
Entry<K,V> p = t.parent; |
1678 |
Entry<K,V> ch = t; |
1679 |
while (p != null && ch == p.right) { |
1680 |
ch = p; |
1681 |
p = p.parent; |
1682 |
} |
1683 |
return p; |
1684 |
} |
1685 |
} |
1686 |
|
1687 |
/** |
1688 |
* Returns the predecessor of the specified Entry, or null if no such. |
1689 |
*/ |
1690 |
private Entry<K,V> predecessor(Entry<K,V> t) { |
1691 |
if (t == null) |
1692 |
return null; |
1693 |
else if (t.left != null) { |
1694 |
Entry<K,V> p = t.left; |
1695 |
while (p.right != null) |
1696 |
p = p.right; |
1697 |
return p; |
1698 |
} else { |
1699 |
Entry<K,V> p = t.parent; |
1700 |
Entry<K,V> ch = t; |
1701 |
while (p != null && ch == p.left) { |
1702 |
ch = p; |
1703 |
p = p.parent; |
1704 |
} |
1705 |
return p; |
1706 |
} |
1707 |
} |
1708 |
|
1709 |
/** |
1710 |
* Balancing operations. |
1711 |
* |
1712 |
* Implementations of rebalancings during insertion and deletion are |
1713 |
* slightly different than the CLR version. Rather than using dummy |
1714 |
* nilnodes, we use a set of accessors that deal properly with null. They |
1715 |
* are used to avoid messiness surrounding nullness checks in the main |
1716 |
* algorithms. |
1717 |
*/ |
1718 |
|
1719 |
private static <K,V> boolean colorOf(Entry<K,V> p) { |
1720 |
return (p == null ? BLACK : p.color); |
1721 |
} |
1722 |
|
1723 |
private static <K,V> Entry<K,V> parentOf(Entry<K,V> p) { |
1724 |
return (p == null ? null: p.parent); |
1725 |
} |
1726 |
|
1727 |
private static <K,V> void setColor(Entry<K,V> p, boolean c) { |
1728 |
if (p != null) |
1729 |
p.color = c; |
1730 |
} |
1731 |
|
1732 |
private static <K,V> Entry<K,V> leftOf(Entry<K,V> p) { |
1733 |
return (p == null) ? null: p.left; |
1734 |
} |
1735 |
|
1736 |
private static <K,V> Entry<K,V> rightOf(Entry<K,V> p) { |
1737 |
return (p == null) ? null: p.right; |
1738 |
} |
1739 |
|
1740 |
/** From CLR **/ |
1741 |
private void rotateLeft(Entry<K,V> p) { |
1742 |
Entry<K,V> r = p.right; |
1743 |
p.right = r.left; |
1744 |
if (r.left != null) |
1745 |
r.left.parent = p; |
1746 |
r.parent = p.parent; |
1747 |
if (p.parent == null) |
1748 |
root = r; |
1749 |
else if (p.parent.left == p) |
1750 |
p.parent.left = r; |
1751 |
else |
1752 |
p.parent.right = r; |
1753 |
r.left = p; |
1754 |
p.parent = r; |
1755 |
} |
1756 |
|
1757 |
/** From CLR **/ |
1758 |
private void rotateRight(Entry<K,V> p) { |
1759 |
Entry<K,V> l = p.left; |
1760 |
p.left = l.right; |
1761 |
if (l.right != null) l.right.parent = p; |
1762 |
l.parent = p.parent; |
1763 |
if (p.parent == null) |
1764 |
root = l; |
1765 |
else if (p.parent.right == p) |
1766 |
p.parent.right = l; |
1767 |
else p.parent.left = l; |
1768 |
l.right = p; |
1769 |
p.parent = l; |
1770 |
} |
1771 |
|
1772 |
|
1773 |
/** From CLR **/ |
1774 |
private void fixAfterInsertion(Entry<K,V> x) { |
1775 |
x.color = RED; |
1776 |
|
1777 |
while (x != null && x != root && x.parent.color == RED) { |
1778 |
if (parentOf(x) == leftOf(parentOf(parentOf(x)))) { |
1779 |
Entry<K,V> y = rightOf(parentOf(parentOf(x))); |
1780 |
if (colorOf(y) == RED) { |
1781 |
setColor(parentOf(x), BLACK); |
1782 |
setColor(y, BLACK); |
1783 |
setColor(parentOf(parentOf(x)), RED); |
1784 |
x = parentOf(parentOf(x)); |
1785 |
} else { |
1786 |
if (x == rightOf(parentOf(x))) { |
1787 |
x = parentOf(x); |
1788 |
rotateLeft(x); |
1789 |
} |
1790 |
setColor(parentOf(x), BLACK); |
1791 |
setColor(parentOf(parentOf(x)), RED); |
1792 |
if (parentOf(parentOf(x)) != null) |
1793 |
rotateRight(parentOf(parentOf(x))); |
1794 |
} |
1795 |
} else { |
1796 |
Entry<K,V> y = leftOf(parentOf(parentOf(x))); |
1797 |
if (colorOf(y) == RED) { |
1798 |
setColor(parentOf(x), BLACK); |
1799 |
setColor(y, BLACK); |
1800 |
setColor(parentOf(parentOf(x)), RED); |
1801 |
x = parentOf(parentOf(x)); |
1802 |
} else { |
1803 |
if (x == leftOf(parentOf(x))) { |
1804 |
x = parentOf(x); |
1805 |
rotateRight(x); |
1806 |
} |
1807 |
setColor(parentOf(x), BLACK); |
1808 |
setColor(parentOf(parentOf(x)), RED); |
1809 |
if (parentOf(parentOf(x)) != null) |
1810 |
rotateLeft(parentOf(parentOf(x))); |
1811 |
} |
1812 |
} |
1813 |
} |
1814 |
root.color = BLACK; |
1815 |
} |
1816 |
|
1817 |
/** |
1818 |
* Delete node p, and then rebalance the tree. |
1819 |
*/ |
1820 |
|
1821 |
private void deleteEntry(Entry<K,V> p) { |
1822 |
decrementSize(); |
1823 |
|
1824 |
// If strictly internal, copy successor's element to p and then make p |
1825 |
// point to successor. |
1826 |
if (p.left != null && p.right != null) { |
1827 |
Entry<K,V> s = successor (p); |
1828 |
p.key = s.key; |
1829 |
p.value = s.value; |
1830 |
p = s; |
1831 |
} // p has 2 children |
1832 |
|
1833 |
// Start fixup at replacement node, if it exists. |
1834 |
Entry<K,V> replacement = (p.left != null ? p.left : p.right); |
1835 |
|
1836 |
if (replacement != null) { |
1837 |
// Link replacement to parent |
1838 |
replacement.parent = p.parent; |
1839 |
if (p.parent == null) |
1840 |
root = replacement; |
1841 |
else if (p == p.parent.left) |
1842 |
p.parent.left = replacement; |
1843 |
else |
1844 |
p.parent.right = replacement; |
1845 |
|
1846 |
// Null out links so they are OK to use by fixAfterDeletion. |
1847 |
p.left = p.right = p.parent = null; |
1848 |
|
1849 |
// Fix replacement |
1850 |
if (p.color == BLACK) |
1851 |
fixAfterDeletion(replacement); |
1852 |
} else if (p.parent == null) { // return if we are the only node. |
1853 |
root = null; |
1854 |
} else { // No children. Use self as phantom replacement and unlink. |
1855 |
if (p.color == BLACK) |
1856 |
fixAfterDeletion(p); |
1857 |
|
1858 |
if (p.parent != null) { |
1859 |
if (p == p.parent.left) |
1860 |
p.parent.left = null; |
1861 |
else if (p == p.parent.right) |
1862 |
p.parent.right = null; |
1863 |
p.parent = null; |
1864 |
} |
1865 |
} |
1866 |
} |
1867 |
|
1868 |
/** From CLR **/ |
1869 |
private void fixAfterDeletion(Entry<K,V> x) { |
1870 |
while (x != root && colorOf(x) == BLACK) { |
1871 |
if (x == leftOf(parentOf(x))) { |
1872 |
Entry<K,V> sib = rightOf(parentOf(x)); |
1873 |
|
1874 |
if (colorOf(sib) == RED) { |
1875 |
setColor(sib, BLACK); |
1876 |
setColor(parentOf(x), RED); |
1877 |
rotateLeft(parentOf(x)); |
1878 |
sib = rightOf(parentOf(x)); |
1879 |
} |
1880 |
|
1881 |
if (colorOf(leftOf(sib)) == BLACK && |
1882 |
colorOf(rightOf(sib)) == BLACK) { |
1883 |
setColor(sib, RED); |
1884 |
x = parentOf(x); |
1885 |
} else { |
1886 |
if (colorOf(rightOf(sib)) == BLACK) { |
1887 |
setColor(leftOf(sib), BLACK); |
1888 |
setColor(sib, RED); |
1889 |
rotateRight(sib); |
1890 |
sib = rightOf(parentOf(x)); |
1891 |
} |
1892 |
setColor(sib, colorOf(parentOf(x))); |
1893 |
setColor(parentOf(x), BLACK); |
1894 |
setColor(rightOf(sib), BLACK); |
1895 |
rotateLeft(parentOf(x)); |
1896 |
x = root; |
1897 |
} |
1898 |
} else { // symmetric |
1899 |
Entry<K,V> sib = leftOf(parentOf(x)); |
1900 |
|
1901 |
if (colorOf(sib) == RED) { |
1902 |
setColor(sib, BLACK); |
1903 |
setColor(parentOf(x), RED); |
1904 |
rotateRight(parentOf(x)); |
1905 |
sib = leftOf(parentOf(x)); |
1906 |
} |
1907 |
|
1908 |
if (colorOf(rightOf(sib)) == BLACK && |
1909 |
colorOf(leftOf(sib)) == BLACK) { |
1910 |
setColor(sib, RED); |
1911 |
x = parentOf(x); |
1912 |
} else { |
1913 |
if (colorOf(leftOf(sib)) == BLACK) { |
1914 |
setColor(rightOf(sib), BLACK); |
1915 |
setColor(sib, RED); |
1916 |
rotateLeft(sib); |
1917 |
sib = leftOf(parentOf(x)); |
1918 |
} |
1919 |
setColor(sib, colorOf(parentOf(x))); |
1920 |
setColor(parentOf(x), BLACK); |
1921 |
setColor(leftOf(sib), BLACK); |
1922 |
rotateRight(parentOf(x)); |
1923 |
x = root; |
1924 |
} |
1925 |
} |
1926 |
} |
1927 |
|
1928 |
setColor(x, BLACK); |
1929 |
} |
1930 |
|
1931 |
private static final long serialVersionUID = 919286545866124006L; |
1932 |
|
1933 |
/** |
1934 |
* Save the state of the <tt>TreeMap</tt> instance to a stream (i.e., |
1935 |
* serialize it). |
1936 |
* |
1937 |
* @serialData The <i>size</i> of the TreeMap (the number of key-value |
1938 |
* mappings) is emitted (int), followed by the key (Object) |
1939 |
* and value (Object) for each key-value mapping represented |
1940 |
* by the TreeMap. The key-value mappings are emitted in |
1941 |
* key-order (as determined by the TreeMap's Comparator, |
1942 |
* or by the keys' natural ordering if the TreeMap has no |
1943 |
* Comparator). |
1944 |
*/ |
1945 |
private void writeObject(java.io.ObjectOutputStream s) |
1946 |
throws java.io.IOException { |
1947 |
// Write out the Comparator and any hidden stuff |
1948 |
s.defaultWriteObject(); |
1949 |
|
1950 |
// Write out size (number of Mappings) |
1951 |
s.writeInt(size); |
1952 |
|
1953 |
// Write out keys and values (alternating) |
1954 |
for (Iterator<Map.Entry<K,V>> i = entrySet().iterator(); i.hasNext(); ) { |
1955 |
Map.Entry<K,V> e = i.next(); |
1956 |
s.writeObject(e.getKey()); |
1957 |
s.writeObject(e.getValue()); |
1958 |
} |
1959 |
} |
1960 |
|
1961 |
|
1962 |
|
1963 |
/** |
1964 |
* Reconstitute the <tt>TreeMap</tt> instance from a stream (i.e., |
1965 |
* deserialize it). |
1966 |
*/ |
1967 |
private void readObject(final java.io.ObjectInputStream s) |
1968 |
throws java.io.IOException, ClassNotFoundException { |
1969 |
// Read in the Comparator and any hidden stuff |
1970 |
s.defaultReadObject(); |
1971 |
|
1972 |
// Read in size |
1973 |
int size = s.readInt(); |
1974 |
|
1975 |
buildFromSorted(size, null, s, null); |
1976 |
} |
1977 |
|
1978 |
/** Intended to be called only from TreeSet.readObject **/ |
1979 |
void readTreeSet(int size, java.io.ObjectInputStream s, V defaultVal) |
1980 |
throws java.io.IOException, ClassNotFoundException { |
1981 |
buildFromSorted(size, null, s, defaultVal); |
1982 |
} |
1983 |
|
1984 |
/** Intended to be called only from TreeSet.addAll **/ |
1985 |
void addAllForTreeSet(SortedSet<? extends K> set, V defaultVal) { |
1986 |
try { |
1987 |
buildFromSorted(set.size(), set.iterator(), null, defaultVal); |
1988 |
} catch (java.io.IOException cannotHappen) { |
1989 |
} catch (ClassNotFoundException cannotHappen) { |
1990 |
} |
1991 |
} |
1992 |
|
1993 |
|
1994 |
/** |
1995 |
* Linear time tree building algorithm from sorted data. Can accept keys |
1996 |
* and/or values from iterator or stream. This leads to too many |
1997 |
* parameters, but seems better than alternatives. The four formats |
1998 |
* that this method accepts are: |
1999 |
* |
2000 |
* 1) An iterator of Map.Entries. (it != null, defaultVal == null). |
2001 |
* 2) An iterator of keys. (it != null, defaultVal != null). |
2002 |
* 3) A stream of alternating serialized keys and values. |
2003 |
* (it == null, defaultVal == null). |
2004 |
* 4) A stream of serialized keys. (it == null, defaultVal != null). |
2005 |
* |
2006 |
* It is assumed that the comparator of the TreeMap is already set prior |
2007 |
* to calling this method. |
2008 |
* |
2009 |
* @param size the number of keys (or key-value pairs) to be read from |
2010 |
* the iterator or stream |
2011 |
* @param it If non-null, new entries are created from entries |
2012 |
* or keys read from this iterator. |
2013 |
* @param str If non-null, new entries are created from keys and |
2014 |
* possibly values read from this stream in serialized form. |
2015 |
* Exactly one of it and str should be non-null. |
2016 |
* @param defaultVal if non-null, this default value is used for |
2017 |
* each value in the map. If null, each value is read from |
2018 |
* iterator or stream, as described above. |
2019 |
* @throws IOException propagated from stream reads. This cannot |
2020 |
* occur if str is null. |
2021 |
* @throws ClassNotFoundException propagated from readObject. |
2022 |
* This cannot occur if str is null. |
2023 |
*/ |
2024 |
private |
2025 |
void buildFromSorted(int size, Iterator it, |
2026 |
java.io.ObjectInputStream str, |
2027 |
V defaultVal) |
2028 |
throws java.io.IOException, ClassNotFoundException { |
2029 |
this.size = size; |
2030 |
root = |
2031 |
buildFromSorted(0, 0, size-1, computeRedLevel(size), |
2032 |
it, str, defaultVal); |
2033 |
} |
2034 |
|
2035 |
/** |
2036 |
* Recursive "helper method" that does the real work of the |
2037 |
* of the previous method. Identically named parameters have |
2038 |
* identical definitions. Additional parameters are documented below. |
2039 |
* It is assumed that the comparator and size fields of the TreeMap are |
2040 |
* already set prior to calling this method. (It ignores both fields.) |
2041 |
* |
2042 |
* @param level the current level of tree. Initial call should be 0. |
2043 |
* @param lo the first element index of this subtree. Initial should be 0. |
2044 |
* @param hi the last element index of this subtree. Initial should be |
2045 |
* size-1. |
2046 |
* @param redLevel the level at which nodes should be red. |
2047 |
* Must be equal to computeRedLevel for tree of this size. |
2048 |
*/ |
2049 |
private final Entry<K,V> buildFromSorted(int level, int lo, int hi, |
2050 |
int redLevel, |
2051 |
Iterator it, |
2052 |
java.io.ObjectInputStream str, |
2053 |
V defaultVal) |
2054 |
throws java.io.IOException, ClassNotFoundException { |
2055 |
/* |
2056 |
* Strategy: The root is the middlemost element. To get to it, we |
2057 |
* have to first recursively construct the entire left subtree, |
2058 |
* so as to grab all of its elements. We can then proceed with right |
2059 |
* subtree. |
2060 |
* |
2061 |
* The lo and hi arguments are the minimum and maximum |
2062 |
* indices to pull out of the iterator or stream for current subtree. |
2063 |
* They are not actually indexed, we just proceed sequentially, |
2064 |
* ensuring that items are extracted in corresponding order. |
2065 |
*/ |
2066 |
|
2067 |
if (hi < lo) return null; |
2068 |
|
2069 |
int mid = (lo + hi) / 2; |
2070 |
|
2071 |
Entry<K,V> left = null; |
2072 |
if (lo < mid) |
2073 |
left = buildFromSorted(level+1, lo, mid - 1, redLevel, |
2074 |
it, str, defaultVal); |
2075 |
|
2076 |
// extract key and/or value from iterator or stream |
2077 |
K key; |
2078 |
V value; |
2079 |
if (it != null) { |
2080 |
if (defaultVal==null) { |
2081 |
Map.Entry<K,V> entry = (Map.Entry<K,V>)it.next(); |
2082 |
key = entry.getKey(); |
2083 |
value = entry.getValue(); |
2084 |
} else { |
2085 |
key = (K)it.next(); |
2086 |
value = defaultVal; |
2087 |
} |
2088 |
} else { // use stream |
2089 |
key = (K) str.readObject(); |
2090 |
value = (defaultVal != null ? defaultVal : (V) str.readObject()); |
2091 |
} |
2092 |
|
2093 |
Entry<K,V> middle = new Entry<K,V>(key, value, null); |
2094 |
|
2095 |
// color nodes in non-full bottommost level red |
2096 |
if (level == redLevel) |
2097 |
middle.color = RED; |
2098 |
|
2099 |
if (left != null) { |
2100 |
middle.left = left; |
2101 |
left.parent = middle; |
2102 |
} |
2103 |
|
2104 |
if (mid < hi) { |
2105 |
Entry<K,V> right = buildFromSorted(level+1, mid+1, hi, redLevel, |
2106 |
it, str, defaultVal); |
2107 |
middle.right = right; |
2108 |
right.parent = middle; |
2109 |
} |
2110 |
|
2111 |
return middle; |
2112 |
} |
2113 |
|
2114 |
/** |
2115 |
* Find the level down to which to assign all nodes BLACK. This is the |
2116 |
* last `full' level of the complete binary tree produced by |
2117 |
* buildTree. The remaining nodes are colored RED. (This makes a `nice' |
2118 |
* set of color assignments wrt future insertions.) This level number is |
2119 |
* computed by finding the number of splits needed to reach the zeroeth |
2120 |
* node. (The answer is ~lg(N), but in any case must be computed by same |
2121 |
* quick O(lg(N)) loop.) |
2122 |
*/ |
2123 |
private static int computeRedLevel(int sz) { |
2124 |
int level = 0; |
2125 |
for (int m = sz - 1; m >= 0; m = m / 2 - 1) |
2126 |
level++; |
2127 |
return level; |
2128 |
} |
2129 |
} |