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1.1 |
/* |
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* %W% %E% |
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* |
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jsr166 |
1.6 |
* Copyright 2005 Sun Microsystems, Inc. All rights reserved. |
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1.1 |
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
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*/ |
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jsr166 |
1.8 |
package java.util; |
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jsr166 |
1.16 |
import java.util.*; // for javadoc (till 6280605 is fixed) |
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1.1 |
|
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/** |
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1.11 |
* A {@link NavigableSet} implementation based on a {@link TreeMap}. |
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* The elements are ordered using their {@linkplain Comparable natural |
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* ordering}, or by a {@link Comparator} provided at set creation |
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* time, depending on which constructor is used. |
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1.1 |
* |
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1.11 |
* <p>This implementation provides guaranteed log(n) time cost for the basic |
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* operations (<tt>add</tt>, <tt>remove</tt> and <tt>contains</tt>). |
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1.1 |
* |
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1.11 |
* <p>Note that the ordering maintained by a set (whether or not an explicit |
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1.1 |
* comparator is provided) must be <i>consistent with equals</i> if it is to |
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* correctly implement the <tt>Set</tt> interface. (See <tt>Comparable</tt> |
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* or <tt>Comparator</tt> for a precise definition of <i>consistent with |
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* equals</i>.) This is so because the <tt>Set</tt> interface is defined in |
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* terms of the <tt>equals</tt> operation, but a <tt>TreeSet</tt> instance |
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* performs all element comparisons using its <tt>compareTo</tt> (or |
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* <tt>compare</tt>) method, so two elements that are deemed equal by this method |
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* are, from the standpoint of the set, equal. The behavior of a set |
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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>Set</tt> interface. |
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* |
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1.11 |
* <p><b>Note that this implementation is not synchronized.</b> If multiple |
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* threads access a set concurrently, and at least one of the threads modifies |
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* the set, it <i>must</i> be synchronized externally. This is typically |
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* accomplished by synchronizing on some object that naturally encapsulates |
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* the set. If no such object exists, the set should be "wrapped" using the |
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* <tt>Collections.synchronizedSet</tt> method. This is best done at creation |
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* time, to prevent accidental unsynchronized access to the set: <pre> |
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* SortedSet s = Collections.synchronizedSortedSet(new TreeSet(...)); |
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1.11 |
* </pre> |
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1.1 |
* |
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1.11 |
* <p>The iterators returned by this class's <tt>iterator</tt> method are |
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* <i>fail-fast</i>: if the set is modified at any time after the iterator is |
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* created, in any way except through the iterator's own <tt>remove</tt> |
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1.11 |
* method, the iterator will throw a {@link ConcurrentModificationException}. |
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1.1 |
* Thus, in the face of concurrent modification, the iterator fails quickly |
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* and cleanly, rather than risking arbitrary, non-deterministic behavior at |
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* 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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1.10 |
* should be used only to detect bugs.</i> |
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1.1 |
* |
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1.10 |
* <p>This class is a member of the |
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1.1 |
* <a href="{@docRoot}/../guide/collections/index.html"> |
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* Java Collections Framework</a>. |
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* |
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1.11 |
* @param <E> the type of elements maintained by this set |
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* |
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1.1 |
* @author Josh Bloch |
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* @version %I%, %G% |
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* @see Collection |
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* @see Set |
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* @see HashSet |
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* @see Comparable |
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* @see Comparator |
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* @see Collections#synchronizedSortedSet(SortedSet) |
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* @see TreeMap |
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* @since 1.2 |
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*/ |
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public class TreeSet<E> |
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extends AbstractSet<E> |
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implements NavigableSet<E>, Cloneable, java.io.Serializable |
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{ |
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private transient NavigableMap<E,Object> m; // The backing Map |
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// Dummy value to associate with an Object in the backing Map |
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private static final Object PRESENT = new Object(); |
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/** |
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jsr166 |
1.11 |
* Constructs a set backed by the specified navigable map. |
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1.1 |
*/ |
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private TreeSet(NavigableMap<E,Object> m) { |
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this.m = m; |
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} |
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/** |
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jsr166 |
1.11 |
* Constructs a new, empty tree set, sorted according to the |
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* natural ordering of its elements. All elements inserted into |
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* the set must implement the {@link Comparable} interface. |
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* Furthermore, all such elements must be <i>mutually |
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* comparable</i>: <tt>e1.compareTo(e2)</tt> must not throw a |
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1.1 |
* <tt>ClassCastException</tt> for any elements <tt>e1</tt> and |
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jsr166 |
1.11 |
* <tt>e2</tt> in the set. If the user attempts to add an element |
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* to the set that violates this constraint (for example, the user |
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* attempts to add a string element to a set whose elements are |
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* integers), the <tt>add(Object)</tt> call will throw a |
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* <tt>ClassCastException</tt>. |
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1.1 |
*/ |
105 |
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public TreeSet() { |
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this(new TreeMap<E,Object>()); |
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} |
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/** |
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jsr166 |
1.12 |
* Constructs a new, empty tree set, sorted according to the specified |
111 |
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* comparator. All elements inserted into the set must be <i>mutually |
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* comparable</i> by the specified comparator: <tt>comparator.compare(e1, |
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* e2)</tt> must not throw a <tt>ClassCastException</tt> for any elements |
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* <tt>e1</tt> and <tt>e2</tt> in the set. If the user attempts to add |
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* an element to the set that violates this constraint, the |
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* <tt>add(Object)</tt> call will throw a <tt>ClassCastException</tt>. |
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jsr166 |
1.11 |
* |
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* @param comparator the comparator that will be used to order this set. |
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* If <tt>null</tt>, the {@linkplain Comparable natural |
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* ordering} of the elements will be used. |
121 |
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*/ |
122 |
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public TreeSet(Comparator<? super E> comparator) { |
123 |
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this(new TreeMap<E,Object>(comparator)); |
124 |
dl |
1.1 |
} |
125 |
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/** |
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jsr166 |
1.12 |
* Constructs a new tree set containing the elements in the specified |
128 |
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* collection, sorted according to the <i>natural ordering</i> of its |
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* elements. All elements inserted into the set must implement the |
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* {@link Comparable} interface. Furthermore, all such elements must be |
131 |
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* <i>mutually comparable</i>: <tt>e1.compareTo(e2)</tt> must not throw a |
132 |
jsr166 |
1.11 |
* <tt>ClassCastException</tt> for any elements <tt>e1</tt> and |
133 |
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* <tt>e2</tt> in the set. |
134 |
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* |
135 |
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* @param c collection whose elements will comprise the new set |
136 |
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* @throws ClassCastException if the elements in <tt>c</tt> are |
137 |
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* not {@link Comparable}, or are not mutually comparable |
138 |
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* @throws NullPointerException if the specified collection is null |
139 |
dl |
1.1 |
*/ |
140 |
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public TreeSet(Collection<? extends E> c) { |
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this(); |
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addAll(c); |
143 |
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} |
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145 |
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/** |
146 |
jsr166 |
1.11 |
* Constructs a new tree set containing the same elements and |
147 |
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* using the same ordering as the specified sorted set. |
148 |
dl |
1.1 |
* |
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jsr166 |
1.11 |
* @param s sorted set whose elements will comprise the new set |
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* @throws NullPointerException if the specified sorted set is null |
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1.1 |
*/ |
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public TreeSet(SortedSet<E> s) { |
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this(s.comparator()); |
154 |
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addAll(s); |
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} |
156 |
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/** |
158 |
jsr166 |
1.13 |
* Returns an iterator over the elements in this set in ascending order. |
159 |
dl |
1.1 |
* |
160 |
jsr166 |
1.13 |
* @return an iterator over the elements in this set in ascending order |
161 |
dl |
1.1 |
*/ |
162 |
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public Iterator<E> iterator() { |
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jsr166 |
1.11 |
return m.keySet().iterator(); |
164 |
dl |
1.1 |
} |
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/** |
167 |
jsr166 |
1.13 |
* Returns an iterator over the elements in this set in descending order. |
168 |
dl |
1.1 |
* |
169 |
jsr166 |
1.13 |
* @return an iterator over the elements in this set in descending order |
170 |
jsr166 |
1.17 |
* @since 1.6 |
171 |
dl |
1.1 |
*/ |
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public Iterator<E> descendingIterator() { |
173 |
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return m.descendingKeySet().iterator(); |
174 |
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} |
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/** |
177 |
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* Returns the number of elements in this set (its cardinality). |
178 |
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* |
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jsr166 |
1.11 |
* @return the number of elements in this set (its cardinality) |
180 |
dl |
1.1 |
*/ |
181 |
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public int size() { |
182 |
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return m.size(); |
183 |
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} |
184 |
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185 |
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/** |
186 |
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* Returns <tt>true</tt> if this set contains no elements. |
187 |
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* |
188 |
jsr166 |
1.11 |
* @return <tt>true</tt> if this set contains no elements |
189 |
dl |
1.1 |
*/ |
190 |
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public boolean isEmpty() { |
191 |
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return m.isEmpty(); |
192 |
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} |
193 |
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194 |
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/** |
195 |
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* Returns <tt>true</tt> if this set contains the specified element. |
196 |
jsr166 |
1.16 |
* More formally, returns <tt>true</tt> if and only if this set |
197 |
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* contains an element <tt>e</tt> such that |
198 |
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* <tt>(o==null ? e==null : o.equals(e))</tt>. |
199 |
dl |
1.1 |
* |
200 |
jsr166 |
1.16 |
* @param o object to be checked for containment in this set |
201 |
jsr166 |
1.11 |
* @return <tt>true</tt> if this set contains the specified element |
202 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
203 |
jsr166 |
1.11 |
* with the elements currently in the set |
204 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
205 |
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* and this set uses natural ordering, or its comparator |
206 |
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* does not permit null elements |
207 |
dl |
1.1 |
*/ |
208 |
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public boolean contains(Object o) { |
209 |
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return m.containsKey(o); |
210 |
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} |
211 |
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212 |
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/** |
213 |
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* Adds the specified element to this set if it is not already present. |
214 |
jsr166 |
1.16 |
* More formally, adds the specified element <tt>e</tt> to this set if |
215 |
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* the set contains no element <tt>e2</tt> such that |
216 |
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* <tt>(e==null ? e2==null : e.equals(e2))</tt>. |
217 |
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* If this set already contains the element, the call leaves the set |
218 |
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* unchanged and returns <tt>false</tt>. |
219 |
dl |
1.1 |
* |
220 |
jsr166 |
1.11 |
* @param e element to be added to this set |
221 |
jsr166 |
1.16 |
* @return <tt>true</tt> if this set did not already contain the specified |
222 |
jsr166 |
1.11 |
* element |
223 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
224 |
jsr166 |
1.16 |
* with the elements currently in this set |
225 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
226 |
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* and this set uses natural ordering, or its comparator |
227 |
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* does not permit null elements |
228 |
dl |
1.1 |
*/ |
229 |
jsr166 |
1.7 |
public boolean add(E e) { |
230 |
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return m.put(e, PRESENT)==null; |
231 |
dl |
1.1 |
} |
232 |
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233 |
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/** |
234 |
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* Removes the specified element from this set if it is present. |
235 |
jsr166 |
1.16 |
* More formally, removes an element <tt>e</tt> such that |
236 |
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* <tt>(o==null ? e==null : o.equals(e))</tt>, |
237 |
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* if this set contains such an element. Returns <tt>true</tt> if |
238 |
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* this set contained the element (or equivalently, if this set |
239 |
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* changed as a result of the call). (This set will not contain the |
240 |
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* element once the call returns.) |
241 |
dl |
1.1 |
* |
242 |
jsr166 |
1.11 |
* @param o object to be removed from this set, if present |
243 |
jsr166 |
1.16 |
* @return <tt>true</tt> if this set contained the specified element |
244 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
245 |
jsr166 |
1.16 |
* with the elements currently in this set |
246 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
247 |
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* and this set uses natural ordering, or its comparator |
248 |
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* does not permit null elements |
249 |
dl |
1.1 |
*/ |
250 |
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public boolean remove(Object o) { |
251 |
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return m.remove(o)==PRESENT; |
252 |
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} |
253 |
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254 |
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/** |
255 |
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* Removes all of the elements from this set. |
256 |
jsr166 |
1.11 |
* The set will be empty after this call returns. |
257 |
dl |
1.1 |
*/ |
258 |
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public void clear() { |
259 |
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m.clear(); |
260 |
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} |
261 |
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262 |
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/** |
263 |
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* Adds all of the elements in the specified collection to this set. |
264 |
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* |
265 |
jsr166 |
1.14 |
* @param c collection containing elements to be added to this set |
266 |
jsr166 |
1.11 |
* @return <tt>true</tt> if this set changed as a result of the call |
267 |
dl |
1.1 |
* @throws ClassCastException if the elements provided cannot be compared |
268 |
jsr166 |
1.11 |
* with the elements currently in the set |
269 |
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* @throws NullPointerException if the specified collection is null or |
270 |
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* if any element is null and this set uses natural ordering, or |
271 |
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* its comparator does not permit null elements |
272 |
dl |
1.1 |
*/ |
273 |
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public boolean addAll(Collection<? extends E> c) { |
274 |
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// Use linear-time version if applicable |
275 |
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if (m.size()==0 && c.size() > 0 && |
276 |
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c instanceof SortedSet && |
277 |
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m instanceof TreeMap) { |
278 |
jsr166 |
1.9 |
SortedSet<? extends E> set = (SortedSet<? extends E>) c; |
279 |
dl |
1.1 |
TreeMap<E,Object> map = (TreeMap<E, Object>) m; |
280 |
jsr166 |
1.9 |
Comparator<? super E> cc = (Comparator<? super E>) set.comparator(); |
281 |
dl |
1.1 |
Comparator<? super E> mc = map.comparator(); |
282 |
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if (cc==mc || (cc != null && cc.equals(mc))) { |
283 |
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map.addAllForTreeSet(set, PRESENT); |
284 |
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return true; |
285 |
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} |
286 |
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} |
287 |
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return super.addAll(c); |
288 |
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} |
289 |
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290 |
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/** |
291 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
292 |
dl |
1.1 |
* @throws NullPointerException if <tt>fromElement</tt> or |
293 |
jsr166 |
1.11 |
* <tt>toElement</tt> is null and this set uses natural ordering, |
294 |
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* or its comparator does not permit null elements |
295 |
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* @throws IllegalArgumentException {@inheritDoc} |
296 |
jsr166 |
1.17 |
* @since 1.6 |
297 |
dl |
1.1 |
*/ |
298 |
dl |
1.3 |
public NavigableSet<E> navigableSubSet(E fromElement, E toElement) { |
299 |
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return new TreeSet<E>(m.navigableSubMap(fromElement, toElement)); |
300 |
dl |
1.1 |
} |
301 |
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302 |
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/** |
303 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
304 |
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* @throws NullPointerException if <tt>toElement</tt> is null and |
305 |
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* this set uses natural ordering, or its comparator does |
306 |
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* not permit null elements |
307 |
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* @throws IllegalArgumentException {@inheritDoc} |
308 |
jsr166 |
1.17 |
* @since 1.6 |
309 |
dl |
1.1 |
*/ |
310 |
dl |
1.3 |
public NavigableSet<E> navigableHeadSet(E toElement) { |
311 |
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return new TreeSet<E>(m.navigableHeadMap(toElement)); |
312 |
dl |
1.1 |
} |
313 |
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314 |
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/** |
315 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
316 |
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* @throws NullPointerException if <tt>fromElement</tt> is null and |
317 |
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* this set uses natural ordering, or its comparator does |
318 |
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* not permit null elements |
319 |
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* @throws IllegalArgumentException {@inheritDoc} |
320 |
jsr166 |
1.17 |
* @since 1.6 |
321 |
dl |
1.1 |
*/ |
322 |
dl |
1.3 |
public NavigableSet<E> navigableTailSet(E fromElement) { |
323 |
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return new TreeSet<E>(m.navigableTailMap(fromElement)); |
324 |
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} |
325 |
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326 |
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/** |
327 |
jsr166 |
1.11 |
* Equivalent to {@link #navigableSubSet} but with a return type |
328 |
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* conforming to the <tt>SortedSet</tt> interface. |
329 |
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* |
330 |
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* <p>{@inheritDoc} |
331 |
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* |
332 |
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* @throws ClassCastException {@inheritDoc} |
333 |
dl |
1.3 |
* @throws NullPointerException if <tt>fromElement</tt> or |
334 |
jsr166 |
1.11 |
* <tt>toElement</tt> is null and this set uses natural ordering, |
335 |
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* or its comparator does not permit null elements |
336 |
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* @throws IllegalArgumentException {@inheritDoc} |
337 |
dl |
1.3 |
*/ |
338 |
|
|
public SortedSet<E> subSet(E fromElement, E toElement) { |
339 |
|
|
return new TreeSet<E>(m.navigableSubMap(fromElement, toElement)); |
340 |
|
|
} |
341 |
|
|
|
342 |
|
|
/** |
343 |
jsr166 |
1.11 |
* Equivalent to {@link #navigableHeadSet} but with a return type |
344 |
|
|
* conforming to the <tt>SortedSet</tt> interface. |
345 |
|
|
* |
346 |
|
|
* <p>{@inheritDoc} |
347 |
dl |
1.3 |
* |
348 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
349 |
|
|
* @throws NullPointerException if <tt>toElement</tt> is null |
350 |
|
|
* and this set uses natural ordering, or its comparator does |
351 |
|
|
* not permit null elements |
352 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
353 |
dl |
1.3 |
*/ |
354 |
|
|
public SortedSet<E> headSet(E toElement) { |
355 |
|
|
return new TreeSet<E>(m.navigableHeadMap(toElement)); |
356 |
|
|
} |
357 |
|
|
|
358 |
|
|
/** |
359 |
jsr166 |
1.11 |
* Equivalent to {@link #navigableTailSet} but with a return type |
360 |
|
|
* conforming to the <tt>SortedSet</tt> interface. |
361 |
|
|
* |
362 |
|
|
* <p>{@inheritDoc} |
363 |
|
|
* |
364 |
|
|
* @throws ClassCastException {@inheritDoc} |
365 |
|
|
* @throws NullPointerException if <tt>fromElement</tt> is null |
366 |
|
|
* and this set uses natural ordering, or its comparator does |
367 |
|
|
* not permit null elements |
368 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
369 |
dl |
1.3 |
*/ |
370 |
|
|
public SortedSet<E> tailSet(E fromElement) { |
371 |
|
|
return new TreeSet<E>(m.navigableTailMap(fromElement)); |
372 |
dl |
1.1 |
} |
373 |
|
|
|
374 |
|
|
public Comparator<? super E> comparator() { |
375 |
|
|
return m.comparator(); |
376 |
|
|
} |
377 |
|
|
|
378 |
|
|
/** |
379 |
jsr166 |
1.11 |
* @throws NoSuchElementException {@inheritDoc} |
380 |
dl |
1.1 |
*/ |
381 |
|
|
public E first() { |
382 |
|
|
return m.firstKey(); |
383 |
|
|
} |
384 |
|
|
|
385 |
|
|
/** |
386 |
jsr166 |
1.11 |
* @throws NoSuchElementException {@inheritDoc} |
387 |
dl |
1.1 |
*/ |
388 |
|
|
public E last() { |
389 |
|
|
return m.lastKey(); |
390 |
|
|
} |
391 |
|
|
|
392 |
|
|
// NavigableSet API methods |
393 |
|
|
|
394 |
|
|
/** |
395 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
396 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
397 |
|
|
* and this set uses natural ordering, or its comparator |
398 |
|
|
* does not permit null elements |
399 |
jsr166 |
1.17 |
* @since 1.6 |
400 |
dl |
1.1 |
*/ |
401 |
jsr166 |
1.11 |
public E lower(E e) { |
402 |
|
|
return m.lowerKey(e); |
403 |
dl |
1.1 |
} |
404 |
|
|
|
405 |
|
|
/** |
406 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
407 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
408 |
|
|
* and this set uses natural ordering, or its comparator |
409 |
|
|
* does not permit null elements |
410 |
jsr166 |
1.17 |
* @since 1.6 |
411 |
dl |
1.1 |
*/ |
412 |
jsr166 |
1.11 |
public E floor(E e) { |
413 |
|
|
return m.floorKey(e); |
414 |
dl |
1.1 |
} |
415 |
|
|
|
416 |
|
|
/** |
417 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
418 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
419 |
|
|
* and this set uses natural ordering, or its comparator |
420 |
|
|
* does not permit null elements |
421 |
jsr166 |
1.17 |
* @since 1.6 |
422 |
dl |
1.1 |
*/ |
423 |
jsr166 |
1.11 |
public E ceiling(E e) { |
424 |
|
|
return m.ceilingKey(e); |
425 |
dl |
1.1 |
} |
426 |
|
|
|
427 |
|
|
/** |
428 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
429 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
430 |
|
|
* and this set uses natural ordering, or its comparator |
431 |
|
|
* does not permit null elements |
432 |
jsr166 |
1.17 |
* @since 1.6 |
433 |
dl |
1.1 |
*/ |
434 |
jsr166 |
1.7 |
public E higher(E e) { |
435 |
|
|
return m.higherKey(e); |
436 |
dl |
1.1 |
} |
437 |
|
|
|
438 |
jsr166 |
1.17 |
/** |
439 |
|
|
* @since 1.6 |
440 |
|
|
*/ |
441 |
dl |
1.1 |
public E pollFirst() { |
442 |
|
|
Map.Entry<E,?> e = m.pollFirstEntry(); |
443 |
|
|
return (e == null)? null : e.getKey(); |
444 |
|
|
} |
445 |
|
|
|
446 |
jsr166 |
1.17 |
/** |
447 |
|
|
* @since 1.6 |
448 |
|
|
*/ |
449 |
dl |
1.1 |
public E pollLast() { |
450 |
|
|
Map.Entry<E,?> e = m.pollLastEntry(); |
451 |
|
|
return (e == null)? null : e.getKey(); |
452 |
|
|
} |
453 |
|
|
|
454 |
|
|
/** |
455 |
|
|
* Returns a shallow copy of this <tt>TreeSet</tt> instance. (The elements |
456 |
|
|
* themselves are not cloned.) |
457 |
|
|
* |
458 |
jsr166 |
1.11 |
* @return a shallow copy of this set |
459 |
dl |
1.1 |
*/ |
460 |
|
|
public Object clone() { |
461 |
|
|
TreeSet<E> clone = null; |
462 |
|
|
try { |
463 |
|
|
clone = (TreeSet<E>) super.clone(); |
464 |
|
|
} catch (CloneNotSupportedException e) { |
465 |
|
|
throw new InternalError(); |
466 |
|
|
} |
467 |
|
|
|
468 |
|
|
clone.m = new TreeMap<E,Object>(m); |
469 |
|
|
|
470 |
|
|
return clone; |
471 |
|
|
} |
472 |
|
|
|
473 |
|
|
/** |
474 |
|
|
* Save the state of the <tt>TreeSet</tt> instance to a stream (that is, |
475 |
|
|
* serialize it). |
476 |
|
|
* |
477 |
|
|
* @serialData Emits the comparator used to order this set, or |
478 |
jsr166 |
1.11 |
* <tt>null</tt> if it obeys its elements' natural ordering |
479 |
|
|
* (Object), followed by the size of the set (the number of |
480 |
|
|
* elements it contains) (int), followed by all of its |
481 |
|
|
* elements (each an Object) in order (as determined by the |
482 |
|
|
* set's Comparator, or by the elements' natural ordering if |
483 |
dl |
1.1 |
* the set has no Comparator). |
484 |
|
|
*/ |
485 |
|
|
private void writeObject(java.io.ObjectOutputStream s) |
486 |
|
|
throws java.io.IOException { |
487 |
|
|
// Write out any hidden stuff |
488 |
|
|
s.defaultWriteObject(); |
489 |
|
|
|
490 |
|
|
// Write out Comparator |
491 |
|
|
s.writeObject(m.comparator()); |
492 |
|
|
|
493 |
|
|
// Write out size |
494 |
|
|
s.writeInt(m.size()); |
495 |
|
|
|
496 |
|
|
// Write out all elements in the proper order. |
497 |
|
|
for (Iterator i=m.keySet().iterator(); i.hasNext(); ) |
498 |
|
|
s.writeObject(i.next()); |
499 |
|
|
} |
500 |
|
|
|
501 |
|
|
/** |
502 |
|
|
* Reconstitute the <tt>TreeSet</tt> instance from a stream (that is, |
503 |
|
|
* deserialize it). |
504 |
|
|
*/ |
505 |
|
|
private void readObject(java.io.ObjectInputStream s) |
506 |
|
|
throws java.io.IOException, ClassNotFoundException { |
507 |
|
|
// Read in any hidden stuff |
508 |
|
|
s.defaultReadObject(); |
509 |
|
|
|
510 |
|
|
// Read in Comparator |
511 |
jsr166 |
1.9 |
Comparator<? super E> c = (Comparator<? super E>) s.readObject(); |
512 |
dl |
1.1 |
|
513 |
|
|
// Create backing TreeMap |
514 |
|
|
TreeMap<E,Object> tm; |
515 |
|
|
if (c==null) |
516 |
|
|
tm = new TreeMap<E,Object>(); |
517 |
|
|
else |
518 |
|
|
tm = new TreeMap<E,Object>(c); |
519 |
|
|
m = tm; |
520 |
|
|
|
521 |
|
|
// Read in size |
522 |
|
|
int size = s.readInt(); |
523 |
|
|
|
524 |
|
|
tm.readTreeSet(size, s, PRESENT); |
525 |
|
|
} |
526 |
|
|
|
527 |
|
|
private static final long serialVersionUID = -2479143000061671589L; |
528 |
|
|
} |