1 |
dl |
1.1 |
/* |
2 |
jsr166 |
1.26 |
* Copyright 1998-2006 Sun Microsystems, Inc. All Rights Reserved. |
3 |
|
|
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
4 |
dl |
1.1 |
* |
5 |
jsr166 |
1.26 |
* This code is free software; you can redistribute it and/or modify it |
6 |
|
|
* under the terms of the GNU General Public License version 2 only, as |
7 |
|
|
* published by the Free Software Foundation. Sun designates this |
8 |
|
|
* particular file as subject to the "Classpath" exception as provided |
9 |
|
|
* by Sun in the LICENSE file that accompanied this code. |
10 |
|
|
* |
11 |
|
|
* This code is distributed in the hope that it will be useful, but WITHOUT |
12 |
|
|
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
13 |
|
|
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
14 |
|
|
* version 2 for more details (a copy is included in the LICENSE file that |
15 |
|
|
* accompanied this code). |
16 |
|
|
* |
17 |
|
|
* You should have received a copy of the GNU General Public License version |
18 |
|
|
* 2 along with this work; if not, write to the Free Software Foundation, |
19 |
|
|
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
20 |
|
|
* |
21 |
|
|
* Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, |
22 |
|
|
* CA 95054 USA or visit www.sun.com if you need additional information or |
23 |
|
|
* have any questions. |
24 |
dl |
1.1 |
*/ |
25 |
|
|
|
26 |
jsr166 |
1.8 |
package java.util; |
27 |
dl |
1.1 |
|
28 |
|
|
/** |
29 |
jsr166 |
1.11 |
* A {@link NavigableSet} implementation based on a {@link TreeMap}. |
30 |
|
|
* The elements are ordered using their {@linkplain Comparable natural |
31 |
|
|
* ordering}, or by a {@link Comparator} provided at set creation |
32 |
|
|
* time, depending on which constructor is used. |
33 |
dl |
1.1 |
* |
34 |
jsr166 |
1.11 |
* <p>This implementation provides guaranteed log(n) time cost for the basic |
35 |
dl |
1.21 |
* operations ({@code add}, {@code remove} and {@code contains}). |
36 |
dl |
1.1 |
* |
37 |
jsr166 |
1.11 |
* <p>Note that the ordering maintained by a set (whether or not an explicit |
38 |
dl |
1.1 |
* comparator is provided) must be <i>consistent with equals</i> if it is to |
39 |
dl |
1.21 |
* correctly implement the {@code Set} interface. (See {@code Comparable} |
40 |
|
|
* or {@code Comparator} for a precise definition of <i>consistent with |
41 |
|
|
* equals</i>.) This is so because the {@code Set} interface is defined in |
42 |
|
|
* terms of the {@code equals} operation, but a {@code TreeSet} instance |
43 |
|
|
* performs all element comparisons using its {@code compareTo} (or |
44 |
|
|
* {@code compare}) method, so two elements that are deemed equal by this method |
45 |
dl |
1.1 |
* are, from the standpoint of the set, equal. The behavior of a set |
46 |
|
|
* <i>is</i> well-defined even if its ordering is inconsistent with equals; it |
47 |
dl |
1.21 |
* just fails to obey the general contract of the {@code Set} interface. |
48 |
dl |
1.1 |
* |
49 |
jsr166 |
1.18 |
* <p><strong>Note that this implementation is not synchronized.</strong> |
50 |
|
|
* If multiple threads access a tree set concurrently, and at least one |
51 |
|
|
* of the threads modifies the set, it <i>must</i> be synchronized |
52 |
|
|
* externally. This is typically accomplished by synchronizing on some |
53 |
|
|
* object that naturally encapsulates the set. |
54 |
|
|
* If no such object exists, the set should be "wrapped" using the |
55 |
|
|
* {@link Collections#synchronizedSortedSet Collections.synchronizedSortedSet} |
56 |
|
|
* method. This is best done at creation time, to prevent accidental |
57 |
|
|
* unsynchronized access to the set: <pre> |
58 |
|
|
* SortedSet s = Collections.synchronizedSortedSet(new TreeSet(...));</pre> |
59 |
dl |
1.1 |
* |
60 |
dl |
1.21 |
* <p>The iterators returned by this class's {@code iterator} method are |
61 |
dl |
1.1 |
* <i>fail-fast</i>: if the set is modified at any time after the iterator is |
62 |
dl |
1.21 |
* created, in any way except through the iterator's own {@code remove} |
63 |
jsr166 |
1.11 |
* method, the iterator will throw a {@link ConcurrentModificationException}. |
64 |
dl |
1.1 |
* Thus, in the face of concurrent modification, the iterator fails quickly |
65 |
|
|
* and cleanly, rather than risking arbitrary, non-deterministic behavior at |
66 |
|
|
* an undetermined time in the future. |
67 |
|
|
* |
68 |
|
|
* <p>Note that the fail-fast behavior of an iterator cannot be guaranteed |
69 |
|
|
* as it is, generally speaking, impossible to make any hard guarantees in the |
70 |
|
|
* presence of unsynchronized concurrent modification. Fail-fast iterators |
71 |
dl |
1.21 |
* throw {@code ConcurrentModificationException} on a best-effort basis. |
72 |
dl |
1.1 |
* Therefore, it would be wrong to write a program that depended on this |
73 |
|
|
* exception for its correctness: <i>the fail-fast behavior of iterators |
74 |
jsr166 |
1.10 |
* should be used only to detect bugs.</i> |
75 |
dl |
1.1 |
* |
76 |
jsr166 |
1.10 |
* <p>This class is a member of the |
77 |
jsr166 |
1.24 |
* <a href="{@docRoot}/../technotes/guides/collections/index.html"> |
78 |
dl |
1.1 |
* Java Collections Framework</a>. |
79 |
|
|
* |
80 |
jsr166 |
1.11 |
* @param <E> the type of elements maintained by this set |
81 |
|
|
* |
82 |
dl |
1.1 |
* @author Josh Bloch |
83 |
|
|
* @version %I%, %G% |
84 |
|
|
* @see Collection |
85 |
|
|
* @see Set |
86 |
|
|
* @see HashSet |
87 |
|
|
* @see Comparable |
88 |
|
|
* @see Comparator |
89 |
|
|
* @see TreeMap |
90 |
|
|
* @since 1.2 |
91 |
|
|
*/ |
92 |
|
|
|
93 |
dl |
1.21 |
public class TreeSet<E> extends AbstractSet<E> |
94 |
dl |
1.1 |
implements NavigableSet<E>, Cloneable, java.io.Serializable |
95 |
|
|
{ |
96 |
dl |
1.22 |
/** |
97 |
dl |
1.21 |
* The backing map. |
98 |
|
|
*/ |
99 |
dl |
1.22 |
private transient NavigableMap<E,Object> m; |
100 |
dl |
1.1 |
|
101 |
|
|
// Dummy value to associate with an Object in the backing Map |
102 |
|
|
private static final Object PRESENT = new Object(); |
103 |
|
|
|
104 |
|
|
/** |
105 |
jsr166 |
1.11 |
* Constructs a set backed by the specified navigable map. |
106 |
dl |
1.1 |
*/ |
107 |
dl |
1.21 |
TreeSet(NavigableMap<E,Object> m) { |
108 |
dl |
1.1 |
this.m = m; |
109 |
|
|
} |
110 |
|
|
|
111 |
|
|
/** |
112 |
jsr166 |
1.11 |
* Constructs a new, empty tree set, sorted according to the |
113 |
|
|
* natural ordering of its elements. All elements inserted into |
114 |
|
|
* the set must implement the {@link Comparable} interface. |
115 |
|
|
* Furthermore, all such elements must be <i>mutually |
116 |
dl |
1.21 |
* comparable</i>: {@code e1.compareTo(e2)} must not throw a |
117 |
|
|
* {@code ClassCastException} for any elements {@code e1} and |
118 |
|
|
* {@code e2} in the set. If the user attempts to add an element |
119 |
jsr166 |
1.11 |
* to the set that violates this constraint (for example, the user |
120 |
|
|
* attempts to add a string element to a set whose elements are |
121 |
jsr166 |
1.24 |
* integers), the {@code add} call will throw a |
122 |
dl |
1.21 |
* {@code ClassCastException}. |
123 |
dl |
1.1 |
*/ |
124 |
|
|
public TreeSet() { |
125 |
|
|
this(new TreeMap<E,Object>()); |
126 |
|
|
} |
127 |
|
|
|
128 |
|
|
/** |
129 |
jsr166 |
1.12 |
* Constructs a new, empty tree set, sorted according to the specified |
130 |
|
|
* comparator. All elements inserted into the set must be <i>mutually |
131 |
dl |
1.21 |
* comparable</i> by the specified comparator: {@code comparator.compare(e1, |
132 |
|
|
* e2)} must not throw a {@code ClassCastException} for any elements |
133 |
|
|
* {@code e1} and {@code e2} in the set. If the user attempts to add |
134 |
jsr166 |
1.12 |
* an element to the set that violates this constraint, the |
135 |
jsr166 |
1.24 |
* {@code add} call will throw a {@code ClassCastException}. |
136 |
jsr166 |
1.11 |
* |
137 |
|
|
* @param comparator the comparator that will be used to order this set. |
138 |
dl |
1.21 |
* If {@code null}, the {@linkplain Comparable natural |
139 |
jsr166 |
1.11 |
* ordering} of the elements will be used. |
140 |
|
|
*/ |
141 |
|
|
public TreeSet(Comparator<? super E> comparator) { |
142 |
|
|
this(new TreeMap<E,Object>(comparator)); |
143 |
dl |
1.1 |
} |
144 |
|
|
|
145 |
|
|
/** |
146 |
jsr166 |
1.12 |
* Constructs a new tree set containing the elements in the specified |
147 |
|
|
* collection, sorted according to the <i>natural ordering</i> of its |
148 |
|
|
* elements. All elements inserted into the set must implement the |
149 |
|
|
* {@link Comparable} interface. Furthermore, all such elements must be |
150 |
dl |
1.21 |
* <i>mutually comparable</i>: {@code e1.compareTo(e2)} must not throw a |
151 |
|
|
* {@code ClassCastException} for any elements {@code e1} and |
152 |
|
|
* {@code e2} in the set. |
153 |
jsr166 |
1.11 |
* |
154 |
|
|
* @param c collection whose elements will comprise the new set |
155 |
dl |
1.21 |
* @throws ClassCastException if the elements in {@code c} are |
156 |
jsr166 |
1.11 |
* not {@link Comparable}, or are not mutually comparable |
157 |
|
|
* @throws NullPointerException if the specified collection is null |
158 |
dl |
1.1 |
*/ |
159 |
|
|
public TreeSet(Collection<? extends E> c) { |
160 |
|
|
this(); |
161 |
|
|
addAll(c); |
162 |
|
|
} |
163 |
|
|
|
164 |
|
|
/** |
165 |
jsr166 |
1.11 |
* Constructs a new tree set containing the same elements and |
166 |
|
|
* using the same ordering as the specified sorted set. |
167 |
dl |
1.1 |
* |
168 |
jsr166 |
1.11 |
* @param s sorted set whose elements will comprise the new set |
169 |
|
|
* @throws NullPointerException if the specified sorted set is null |
170 |
dl |
1.1 |
*/ |
171 |
|
|
public TreeSet(SortedSet<E> s) { |
172 |
|
|
this(s.comparator()); |
173 |
|
|
addAll(s); |
174 |
|
|
} |
175 |
|
|
|
176 |
|
|
/** |
177 |
jsr166 |
1.13 |
* Returns an iterator over the elements in this set in ascending order. |
178 |
dl |
1.1 |
* |
179 |
jsr166 |
1.13 |
* @return an iterator over the elements in this set in ascending order |
180 |
dl |
1.1 |
*/ |
181 |
|
|
public Iterator<E> iterator() { |
182 |
dl |
1.21 |
return m.navigableKeySet().iterator(); |
183 |
dl |
1.1 |
} |
184 |
|
|
|
185 |
|
|
/** |
186 |
jsr166 |
1.13 |
* Returns an iterator over the elements in this set in descending order. |
187 |
dl |
1.1 |
* |
188 |
jsr166 |
1.13 |
* @return an iterator over the elements in this set in descending order |
189 |
jsr166 |
1.17 |
* @since 1.6 |
190 |
dl |
1.1 |
*/ |
191 |
|
|
public Iterator<E> descendingIterator() { |
192 |
|
|
return m.descendingKeySet().iterator(); |
193 |
|
|
} |
194 |
|
|
|
195 |
|
|
/** |
196 |
dl |
1.21 |
* @since 1.6 |
197 |
|
|
*/ |
198 |
|
|
public NavigableSet<E> descendingSet() { |
199 |
|
|
return new TreeSet(m.descendingMap()); |
200 |
|
|
} |
201 |
|
|
|
202 |
|
|
/** |
203 |
dl |
1.1 |
* Returns the number of elements in this set (its cardinality). |
204 |
|
|
* |
205 |
jsr166 |
1.11 |
* @return the number of elements in this set (its cardinality) |
206 |
dl |
1.1 |
*/ |
207 |
|
|
public int size() { |
208 |
|
|
return m.size(); |
209 |
|
|
} |
210 |
|
|
|
211 |
|
|
/** |
212 |
dl |
1.21 |
* Returns {@code true} if this set contains no elements. |
213 |
dl |
1.1 |
* |
214 |
dl |
1.21 |
* @return {@code true} if this set contains no elements |
215 |
dl |
1.1 |
*/ |
216 |
|
|
public boolean isEmpty() { |
217 |
|
|
return m.isEmpty(); |
218 |
|
|
} |
219 |
|
|
|
220 |
|
|
/** |
221 |
dl |
1.21 |
* Returns {@code true} if this set contains the specified element. |
222 |
|
|
* More formally, returns {@code true} if and only if this set |
223 |
|
|
* contains an element {@code e} such that |
224 |
jsr166 |
1.23 |
* <tt>(o==null ? e==null : o.equals(e))</tt>. |
225 |
dl |
1.1 |
* |
226 |
jsr166 |
1.16 |
* @param o object to be checked for containment in this set |
227 |
dl |
1.21 |
* @return {@code true} if this set contains the specified element |
228 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
229 |
jsr166 |
1.11 |
* with the elements currently in the set |
230 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
231 |
|
|
* and this set uses natural ordering, or its comparator |
232 |
|
|
* does not permit null elements |
233 |
dl |
1.1 |
*/ |
234 |
|
|
public boolean contains(Object o) { |
235 |
|
|
return m.containsKey(o); |
236 |
|
|
} |
237 |
|
|
|
238 |
|
|
/** |
239 |
|
|
* Adds the specified element to this set if it is not already present. |
240 |
dl |
1.21 |
* More formally, adds the specified element {@code e} to this set if |
241 |
|
|
* the set contains no element {@code e2} such that |
242 |
jsr166 |
1.23 |
* <tt>(e==null ? e2==null : e.equals(e2))</tt>. |
243 |
jsr166 |
1.16 |
* If this set already contains the element, the call leaves the set |
244 |
dl |
1.21 |
* unchanged and returns {@code false}. |
245 |
dl |
1.1 |
* |
246 |
jsr166 |
1.11 |
* @param e element to be added to this set |
247 |
dl |
1.21 |
* @return {@code true} if this set did not already contain the specified |
248 |
jsr166 |
1.11 |
* element |
249 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
250 |
jsr166 |
1.16 |
* with the elements currently in this set |
251 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
252 |
|
|
* and this set uses natural ordering, or its comparator |
253 |
|
|
* does not permit null elements |
254 |
dl |
1.1 |
*/ |
255 |
jsr166 |
1.7 |
public boolean add(E e) { |
256 |
|
|
return m.put(e, PRESENT)==null; |
257 |
dl |
1.1 |
} |
258 |
|
|
|
259 |
|
|
/** |
260 |
|
|
* Removes the specified element from this set if it is present. |
261 |
dl |
1.21 |
* More formally, removes an element {@code e} such that |
262 |
jsr166 |
1.23 |
* <tt>(o==null ? e==null : o.equals(e))</tt>, |
263 |
dl |
1.21 |
* if this set contains such an element. Returns {@code true} if |
264 |
jsr166 |
1.16 |
* this set contained the element (or equivalently, if this set |
265 |
|
|
* changed as a result of the call). (This set will not contain the |
266 |
|
|
* element once the call returns.) |
267 |
dl |
1.1 |
* |
268 |
jsr166 |
1.11 |
* @param o object to be removed from this set, if present |
269 |
dl |
1.21 |
* @return {@code true} if this set contained the specified element |
270 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
271 |
jsr166 |
1.16 |
* with the elements currently in this set |
272 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
273 |
|
|
* and this set uses natural ordering, or its comparator |
274 |
|
|
* does not permit null elements |
275 |
dl |
1.1 |
*/ |
276 |
|
|
public boolean remove(Object o) { |
277 |
|
|
return m.remove(o)==PRESENT; |
278 |
|
|
} |
279 |
|
|
|
280 |
|
|
/** |
281 |
|
|
* Removes all of the elements from this set. |
282 |
jsr166 |
1.11 |
* The set will be empty after this call returns. |
283 |
dl |
1.1 |
*/ |
284 |
|
|
public void clear() { |
285 |
|
|
m.clear(); |
286 |
|
|
} |
287 |
|
|
|
288 |
|
|
/** |
289 |
|
|
* Adds all of the elements in the specified collection to this set. |
290 |
|
|
* |
291 |
jsr166 |
1.14 |
* @param c collection containing elements to be added to this set |
292 |
dl |
1.21 |
* @return {@code true} if this set changed as a result of the call |
293 |
dl |
1.1 |
* @throws ClassCastException if the elements provided cannot be compared |
294 |
jsr166 |
1.11 |
* with the elements currently in the set |
295 |
|
|
* @throws NullPointerException if the specified collection is null or |
296 |
|
|
* if any element is null and this set uses natural ordering, or |
297 |
|
|
* its comparator does not permit null elements |
298 |
dl |
1.1 |
*/ |
299 |
|
|
public boolean addAll(Collection<? extends E> c) { |
300 |
|
|
// Use linear-time version if applicable |
301 |
|
|
if (m.size()==0 && c.size() > 0 && |
302 |
|
|
c instanceof SortedSet && |
303 |
|
|
m instanceof TreeMap) { |
304 |
jsr166 |
1.9 |
SortedSet<? extends E> set = (SortedSet<? extends E>) c; |
305 |
dl |
1.1 |
TreeMap<E,Object> map = (TreeMap<E, Object>) m; |
306 |
jsr166 |
1.9 |
Comparator<? super E> cc = (Comparator<? super E>) set.comparator(); |
307 |
dl |
1.1 |
Comparator<? super E> mc = map.comparator(); |
308 |
|
|
if (cc==mc || (cc != null && cc.equals(mc))) { |
309 |
|
|
map.addAllForTreeSet(set, PRESENT); |
310 |
|
|
return true; |
311 |
|
|
} |
312 |
|
|
} |
313 |
|
|
return super.addAll(c); |
314 |
|
|
} |
315 |
|
|
|
316 |
|
|
/** |
317 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
318 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} or {@code toElement} |
319 |
|
|
* is null and this set uses natural ordering, or its comparator |
320 |
|
|
* does not permit null elements |
321 |
jsr166 |
1.11 |
* @throws IllegalArgumentException {@inheritDoc} |
322 |
jsr166 |
1.17 |
* @since 1.6 |
323 |
dl |
1.1 |
*/ |
324 |
dl |
1.22 |
public NavigableSet<E> subSet(E fromElement, boolean fromInclusive, |
325 |
|
|
E toElement, boolean toInclusive) { |
326 |
|
|
return new TreeSet<E>(m.subMap(fromElement, fromInclusive, |
327 |
|
|
toElement, toInclusive)); |
328 |
dl |
1.1 |
} |
329 |
|
|
|
330 |
|
|
/** |
331 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
332 |
dl |
1.21 |
* @throws NullPointerException if {@code toElement} is null and |
333 |
jsr166 |
1.11 |
* this set uses natural ordering, or its comparator does |
334 |
|
|
* not permit null elements |
335 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
336 |
jsr166 |
1.17 |
* @since 1.6 |
337 |
dl |
1.1 |
*/ |
338 |
dl |
1.22 |
public NavigableSet<E> headSet(E toElement, boolean inclusive) { |
339 |
|
|
return new TreeSet<E>(m.headMap(toElement, inclusive)); |
340 |
dl |
1.1 |
} |
341 |
|
|
|
342 |
|
|
/** |
343 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
344 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} is null and |
345 |
jsr166 |
1.11 |
* this set uses natural ordering, or its comparator does |
346 |
|
|
* not permit null elements |
347 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
348 |
jsr166 |
1.17 |
* @since 1.6 |
349 |
dl |
1.1 |
*/ |
350 |
dl |
1.22 |
public NavigableSet<E> tailSet(E fromElement, boolean inclusive) { |
351 |
|
|
return new TreeSet<E>(m.tailMap(fromElement, inclusive)); |
352 |
dl |
1.3 |
} |
353 |
|
|
|
354 |
|
|
/** |
355 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
356 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} or |
357 |
|
|
* {@code toElement} is null and this set uses natural ordering, |
358 |
jsr166 |
1.11 |
* or its comparator does not permit null elements |
359 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
360 |
dl |
1.3 |
*/ |
361 |
|
|
public SortedSet<E> subSet(E fromElement, E toElement) { |
362 |
dl |
1.22 |
return subSet(fromElement, true, toElement, false); |
363 |
dl |
1.3 |
} |
364 |
|
|
|
365 |
|
|
/** |
366 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
367 |
dl |
1.21 |
* @throws NullPointerException if {@code toElement} is null |
368 |
jsr166 |
1.11 |
* and this set uses natural ordering, or its comparator does |
369 |
|
|
* not permit null elements |
370 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
371 |
dl |
1.3 |
*/ |
372 |
|
|
public SortedSet<E> headSet(E toElement) { |
373 |
dl |
1.22 |
return headSet(toElement, false); |
374 |
dl |
1.3 |
} |
375 |
|
|
|
376 |
|
|
/** |
377 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
378 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} is null |
379 |
jsr166 |
1.11 |
* and this set uses natural ordering, or its comparator does |
380 |
|
|
* not permit null elements |
381 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
382 |
dl |
1.3 |
*/ |
383 |
|
|
public SortedSet<E> tailSet(E fromElement) { |
384 |
dl |
1.22 |
return tailSet(fromElement, true); |
385 |
dl |
1.1 |
} |
386 |
|
|
|
387 |
|
|
public Comparator<? super E> comparator() { |
388 |
|
|
return m.comparator(); |
389 |
|
|
} |
390 |
|
|
|
391 |
|
|
/** |
392 |
jsr166 |
1.11 |
* @throws NoSuchElementException {@inheritDoc} |
393 |
dl |
1.1 |
*/ |
394 |
|
|
public E first() { |
395 |
|
|
return m.firstKey(); |
396 |
|
|
} |
397 |
|
|
|
398 |
|
|
/** |
399 |
jsr166 |
1.11 |
* @throws NoSuchElementException {@inheritDoc} |
400 |
dl |
1.1 |
*/ |
401 |
|
|
public E last() { |
402 |
|
|
return m.lastKey(); |
403 |
|
|
} |
404 |
|
|
|
405 |
|
|
// NavigableSet API methods |
406 |
|
|
|
407 |
|
|
/** |
408 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
409 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
410 |
|
|
* and this set uses natural ordering, or its comparator |
411 |
|
|
* does not permit null elements |
412 |
jsr166 |
1.17 |
* @since 1.6 |
413 |
dl |
1.1 |
*/ |
414 |
jsr166 |
1.11 |
public E lower(E e) { |
415 |
|
|
return m.lowerKey(e); |
416 |
dl |
1.1 |
} |
417 |
|
|
|
418 |
|
|
/** |
419 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
420 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
421 |
|
|
* and this set uses natural ordering, or its comparator |
422 |
|
|
* does not permit null elements |
423 |
jsr166 |
1.17 |
* @since 1.6 |
424 |
dl |
1.1 |
*/ |
425 |
jsr166 |
1.11 |
public E floor(E e) { |
426 |
|
|
return m.floorKey(e); |
427 |
dl |
1.1 |
} |
428 |
|
|
|
429 |
|
|
/** |
430 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
431 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
432 |
|
|
* and this set uses natural ordering, or its comparator |
433 |
|
|
* does not permit null elements |
434 |
jsr166 |
1.17 |
* @since 1.6 |
435 |
dl |
1.1 |
*/ |
436 |
jsr166 |
1.11 |
public E ceiling(E e) { |
437 |
|
|
return m.ceilingKey(e); |
438 |
dl |
1.1 |
} |
439 |
|
|
|
440 |
|
|
/** |
441 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
442 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
443 |
|
|
* and this set uses natural ordering, or its comparator |
444 |
|
|
* does not permit null elements |
445 |
jsr166 |
1.17 |
* @since 1.6 |
446 |
dl |
1.1 |
*/ |
447 |
jsr166 |
1.7 |
public E higher(E e) { |
448 |
|
|
return m.higherKey(e); |
449 |
dl |
1.1 |
} |
450 |
|
|
|
451 |
jsr166 |
1.17 |
/** |
452 |
|
|
* @since 1.6 |
453 |
|
|
*/ |
454 |
dl |
1.1 |
public E pollFirst() { |
455 |
|
|
Map.Entry<E,?> e = m.pollFirstEntry(); |
456 |
|
|
return (e == null)? null : e.getKey(); |
457 |
|
|
} |
458 |
|
|
|
459 |
jsr166 |
1.17 |
/** |
460 |
|
|
* @since 1.6 |
461 |
|
|
*/ |
462 |
dl |
1.1 |
public E pollLast() { |
463 |
|
|
Map.Entry<E,?> e = m.pollLastEntry(); |
464 |
|
|
return (e == null)? null : e.getKey(); |
465 |
|
|
} |
466 |
|
|
|
467 |
|
|
/** |
468 |
dl |
1.21 |
* Returns a shallow copy of this {@code TreeSet} instance. (The elements |
469 |
dl |
1.1 |
* themselves are not cloned.) |
470 |
|
|
* |
471 |
jsr166 |
1.11 |
* @return a shallow copy of this set |
472 |
dl |
1.1 |
*/ |
473 |
|
|
public Object clone() { |
474 |
|
|
TreeSet<E> clone = null; |
475 |
|
|
try { |
476 |
|
|
clone = (TreeSet<E>) super.clone(); |
477 |
|
|
} catch (CloneNotSupportedException e) { |
478 |
|
|
throw new InternalError(); |
479 |
|
|
} |
480 |
|
|
|
481 |
|
|
clone.m = new TreeMap<E,Object>(m); |
482 |
|
|
return clone; |
483 |
|
|
} |
484 |
|
|
|
485 |
|
|
/** |
486 |
dl |
1.21 |
* Save the state of the {@code TreeSet} instance to a stream (that is, |
487 |
dl |
1.1 |
* serialize it). |
488 |
|
|
* |
489 |
|
|
* @serialData Emits the comparator used to order this set, or |
490 |
dl |
1.21 |
* {@code null} if it obeys its elements' natural ordering |
491 |
jsr166 |
1.11 |
* (Object), followed by the size of the set (the number of |
492 |
|
|
* elements it contains) (int), followed by all of its |
493 |
|
|
* elements (each an Object) in order (as determined by the |
494 |
|
|
* set's Comparator, or by the elements' natural ordering if |
495 |
dl |
1.1 |
* the set has no Comparator). |
496 |
|
|
*/ |
497 |
|
|
private void writeObject(java.io.ObjectOutputStream s) |
498 |
|
|
throws java.io.IOException { |
499 |
|
|
// Write out any hidden stuff |
500 |
|
|
s.defaultWriteObject(); |
501 |
|
|
|
502 |
|
|
// Write out Comparator |
503 |
|
|
s.writeObject(m.comparator()); |
504 |
|
|
|
505 |
|
|
// Write out size |
506 |
|
|
s.writeInt(m.size()); |
507 |
|
|
|
508 |
|
|
// Write out all elements in the proper order. |
509 |
|
|
for (Iterator i=m.keySet().iterator(); i.hasNext(); ) |
510 |
|
|
s.writeObject(i.next()); |
511 |
|
|
} |
512 |
|
|
|
513 |
|
|
/** |
514 |
dl |
1.21 |
* Reconstitute the {@code TreeSet} instance from a stream (that is, |
515 |
dl |
1.1 |
* deserialize it). |
516 |
|
|
*/ |
517 |
|
|
private void readObject(java.io.ObjectInputStream s) |
518 |
|
|
throws java.io.IOException, ClassNotFoundException { |
519 |
|
|
// Read in any hidden stuff |
520 |
|
|
s.defaultReadObject(); |
521 |
|
|
|
522 |
|
|
// Read in Comparator |
523 |
jsr166 |
1.9 |
Comparator<? super E> c = (Comparator<? super E>) s.readObject(); |
524 |
dl |
1.1 |
|
525 |
|
|
// Create backing TreeMap |
526 |
|
|
TreeMap<E,Object> tm; |
527 |
|
|
if (c==null) |
528 |
|
|
tm = new TreeMap<E,Object>(); |
529 |
|
|
else |
530 |
|
|
tm = new TreeMap<E,Object>(c); |
531 |
|
|
m = tm; |
532 |
|
|
|
533 |
|
|
// Read in size |
534 |
|
|
int size = s.readInt(); |
535 |
|
|
|
536 |
|
|
tm.readTreeSet(size, s, PRESENT); |
537 |
|
|
} |
538 |
|
|
|
539 |
|
|
private static final long serialVersionUID = -2479143000061671589L; |
540 |
|
|
} |