1 |
dl |
1.1 |
/* |
2 |
|
|
* %W% %E% |
3 |
|
|
* |
4 |
jsr166 |
1.19 |
* Copyright 2006 Sun Microsystems, Inc. All rights reserved. |
5 |
dl |
1.1 |
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms. |
6 |
|
|
*/ |
7 |
|
|
|
8 |
jsr166 |
1.8 |
package java.util; |
9 |
dl |
1.1 |
|
10 |
|
|
/** |
11 |
jsr166 |
1.11 |
* A {@link NavigableSet} implementation based on a {@link TreeMap}. |
12 |
|
|
* The elements are ordered using their {@linkplain Comparable natural |
13 |
|
|
* ordering}, or by a {@link Comparator} provided at set creation |
14 |
|
|
* time, depending on which constructor is used. |
15 |
dl |
1.1 |
* |
16 |
jsr166 |
1.11 |
* <p>This implementation provides guaranteed log(n) time cost for the basic |
17 |
dl |
1.21 |
* operations ({@code add}, {@code remove} and {@code contains}). |
18 |
dl |
1.1 |
* |
19 |
jsr166 |
1.11 |
* <p>Note that the ordering maintained by a set (whether or not an explicit |
20 |
dl |
1.1 |
* comparator is provided) must be <i>consistent with equals</i> if it is to |
21 |
dl |
1.21 |
* correctly implement the {@code Set} interface. (See {@code Comparable} |
22 |
|
|
* or {@code Comparator} for a precise definition of <i>consistent with |
23 |
|
|
* equals</i>.) This is so because the {@code Set} interface is defined in |
24 |
|
|
* terms of the {@code equals} operation, but a {@code TreeSet} instance |
25 |
|
|
* performs all element comparisons using its {@code compareTo} (or |
26 |
|
|
* {@code compare}) method, so two elements that are deemed equal by this method |
27 |
dl |
1.1 |
* are, from the standpoint of the set, equal. The behavior of a set |
28 |
|
|
* <i>is</i> well-defined even if its ordering is inconsistent with equals; it |
29 |
dl |
1.21 |
* just fails to obey the general contract of the {@code Set} interface. |
30 |
dl |
1.1 |
* |
31 |
jsr166 |
1.18 |
* <p><strong>Note that this implementation is not synchronized.</strong> |
32 |
|
|
* If multiple threads access a tree set concurrently, and at least one |
33 |
|
|
* of the threads modifies the set, it <i>must</i> be synchronized |
34 |
|
|
* externally. This is typically accomplished by synchronizing on some |
35 |
|
|
* object that naturally encapsulates the set. |
36 |
|
|
* If no such object exists, the set should be "wrapped" using the |
37 |
|
|
* {@link Collections#synchronizedSortedSet Collections.synchronizedSortedSet} |
38 |
|
|
* method. This is best done at creation time, to prevent accidental |
39 |
|
|
* unsynchronized access to the set: <pre> |
40 |
|
|
* SortedSet s = Collections.synchronizedSortedSet(new TreeSet(...));</pre> |
41 |
dl |
1.1 |
* |
42 |
dl |
1.21 |
* <p>The iterators returned by this class's {@code iterator} method are |
43 |
dl |
1.1 |
* <i>fail-fast</i>: if the set is modified at any time after the iterator is |
44 |
dl |
1.21 |
* created, in any way except through the iterator's own {@code remove} |
45 |
jsr166 |
1.11 |
* method, the iterator will throw a {@link ConcurrentModificationException}. |
46 |
dl |
1.1 |
* Thus, in the face of concurrent modification, the iterator fails quickly |
47 |
|
|
* and cleanly, rather than risking arbitrary, non-deterministic behavior at |
48 |
|
|
* an undetermined time in the future. |
49 |
|
|
* |
50 |
|
|
* <p>Note that the fail-fast behavior of an iterator cannot be guaranteed |
51 |
|
|
* as it is, generally speaking, impossible to make any hard guarantees in the |
52 |
|
|
* presence of unsynchronized concurrent modification. Fail-fast iterators |
53 |
dl |
1.21 |
* throw {@code ConcurrentModificationException} on a best-effort basis. |
54 |
dl |
1.1 |
* Therefore, it would be wrong to write a program that depended on this |
55 |
|
|
* exception for its correctness: <i>the fail-fast behavior of iterators |
56 |
jsr166 |
1.10 |
* should be used only to detect bugs.</i> |
57 |
dl |
1.1 |
* |
58 |
jsr166 |
1.10 |
* <p>This class is a member of the |
59 |
dl |
1.1 |
* <a href="{@docRoot}/../guide/collections/index.html"> |
60 |
|
|
* Java Collections Framework</a>. |
61 |
|
|
* |
62 |
jsr166 |
1.11 |
* @param <E> the type of elements maintained by this set |
63 |
|
|
* |
64 |
dl |
1.1 |
* @author Josh Bloch |
65 |
|
|
* @version %I%, %G% |
66 |
|
|
* @see Collection |
67 |
|
|
* @see Set |
68 |
|
|
* @see HashSet |
69 |
|
|
* @see Comparable |
70 |
|
|
* @see Comparator |
71 |
|
|
* @see TreeMap |
72 |
|
|
* @since 1.2 |
73 |
|
|
*/ |
74 |
|
|
|
75 |
dl |
1.21 |
public class TreeSet<E> extends AbstractSet<E> |
76 |
dl |
1.1 |
implements NavigableSet<E>, Cloneable, java.io.Serializable |
77 |
|
|
{ |
78 |
dl |
1.22 |
/** |
79 |
dl |
1.21 |
* The backing map. |
80 |
|
|
*/ |
81 |
dl |
1.22 |
private transient NavigableMap<E,Object> m; |
82 |
dl |
1.1 |
|
83 |
|
|
// Dummy value to associate with an Object in the backing Map |
84 |
|
|
private static final Object PRESENT = new Object(); |
85 |
|
|
|
86 |
|
|
/** |
87 |
jsr166 |
1.11 |
* Constructs a set backed by the specified navigable map. |
88 |
dl |
1.1 |
*/ |
89 |
dl |
1.21 |
TreeSet(NavigableMap<E,Object> m) { |
90 |
dl |
1.1 |
this.m = m; |
91 |
|
|
} |
92 |
|
|
|
93 |
|
|
/** |
94 |
jsr166 |
1.11 |
* Constructs a new, empty tree set, sorted according to the |
95 |
|
|
* natural ordering of its elements. All elements inserted into |
96 |
|
|
* the set must implement the {@link Comparable} interface. |
97 |
|
|
* Furthermore, all such elements must be <i>mutually |
98 |
dl |
1.21 |
* comparable</i>: {@code e1.compareTo(e2)} must not throw a |
99 |
|
|
* {@code ClassCastException} for any elements {@code e1} and |
100 |
|
|
* {@code e2} in the set. If the user attempts to add an element |
101 |
jsr166 |
1.11 |
* to the set that violates this constraint (for example, the user |
102 |
|
|
* attempts to add a string element to a set whose elements are |
103 |
dl |
1.21 |
* integers), the {@code add(Object)} call will throw a |
104 |
|
|
* {@code ClassCastException}. |
105 |
dl |
1.1 |
*/ |
106 |
|
|
public TreeSet() { |
107 |
|
|
this(new TreeMap<E,Object>()); |
108 |
|
|
} |
109 |
|
|
|
110 |
|
|
/** |
111 |
jsr166 |
1.12 |
* Constructs a new, empty tree set, sorted according to the specified |
112 |
|
|
* comparator. All elements inserted into the set must be <i>mutually |
113 |
dl |
1.21 |
* comparable</i> by the specified comparator: {@code comparator.compare(e1, |
114 |
|
|
* e2)} must not throw a {@code ClassCastException} for any elements |
115 |
|
|
* {@code e1} and {@code e2} in the set. If the user attempts to add |
116 |
jsr166 |
1.12 |
* an element to the set that violates this constraint, the |
117 |
dl |
1.21 |
* {@code add(Object)} call will throw a {@code ClassCastException}. |
118 |
jsr166 |
1.11 |
* |
119 |
|
|
* @param comparator the comparator that will be used to order this set. |
120 |
dl |
1.21 |
* If {@code null}, the {@linkplain Comparable natural |
121 |
jsr166 |
1.11 |
* ordering} of the elements will be used. |
122 |
|
|
*/ |
123 |
|
|
public TreeSet(Comparator<? super E> comparator) { |
124 |
|
|
this(new TreeMap<E,Object>(comparator)); |
125 |
dl |
1.1 |
} |
126 |
|
|
|
127 |
|
|
/** |
128 |
jsr166 |
1.12 |
* Constructs a new tree set containing the elements in the specified |
129 |
|
|
* collection, sorted according to the <i>natural ordering</i> of its |
130 |
|
|
* elements. All elements inserted into the set must implement the |
131 |
|
|
* {@link Comparable} interface. Furthermore, all such elements must be |
132 |
dl |
1.21 |
* <i>mutually comparable</i>: {@code e1.compareTo(e2)} must not throw a |
133 |
|
|
* {@code ClassCastException} for any elements {@code e1} and |
134 |
|
|
* {@code e2} in the set. |
135 |
jsr166 |
1.11 |
* |
136 |
|
|
* @param c collection whose elements will comprise the new set |
137 |
dl |
1.21 |
* @throws ClassCastException if the elements in {@code c} are |
138 |
jsr166 |
1.11 |
* not {@link Comparable}, or are not mutually comparable |
139 |
|
|
* @throws NullPointerException if the specified collection is null |
140 |
dl |
1.1 |
*/ |
141 |
|
|
public TreeSet(Collection<? extends E> c) { |
142 |
|
|
this(); |
143 |
|
|
addAll(c); |
144 |
|
|
} |
145 |
|
|
|
146 |
|
|
/** |
147 |
jsr166 |
1.11 |
* Constructs a new tree set containing the same elements and |
148 |
|
|
* using the same ordering as the specified sorted set. |
149 |
dl |
1.1 |
* |
150 |
jsr166 |
1.11 |
* @param s sorted set whose elements will comprise the new set |
151 |
|
|
* @throws NullPointerException if the specified sorted set is null |
152 |
dl |
1.1 |
*/ |
153 |
|
|
public TreeSet(SortedSet<E> s) { |
154 |
|
|
this(s.comparator()); |
155 |
|
|
addAll(s); |
156 |
|
|
} |
157 |
|
|
|
158 |
|
|
/** |
159 |
jsr166 |
1.13 |
* Returns an iterator over the elements in this set in ascending order. |
160 |
dl |
1.1 |
* |
161 |
jsr166 |
1.13 |
* @return an iterator over the elements in this set in ascending order |
162 |
dl |
1.1 |
*/ |
163 |
|
|
public Iterator<E> iterator() { |
164 |
dl |
1.21 |
return m.navigableKeySet().iterator(); |
165 |
dl |
1.1 |
} |
166 |
|
|
|
167 |
|
|
/** |
168 |
jsr166 |
1.13 |
* Returns an iterator over the elements in this set in descending order. |
169 |
dl |
1.1 |
* |
170 |
jsr166 |
1.13 |
* @return an iterator over the elements in this set in descending order |
171 |
jsr166 |
1.17 |
* @since 1.6 |
172 |
dl |
1.1 |
*/ |
173 |
|
|
public Iterator<E> descendingIterator() { |
174 |
|
|
return m.descendingKeySet().iterator(); |
175 |
|
|
} |
176 |
|
|
|
177 |
|
|
/** |
178 |
dl |
1.21 |
* @since 1.6 |
179 |
|
|
*/ |
180 |
|
|
public NavigableSet<E> descendingSet() { |
181 |
|
|
return new TreeSet(m.descendingMap()); |
182 |
|
|
} |
183 |
|
|
|
184 |
|
|
/** |
185 |
dl |
1.1 |
* Returns the number of elements in this set (its cardinality). |
186 |
|
|
* |
187 |
jsr166 |
1.11 |
* @return the number of elements in this set (its cardinality) |
188 |
dl |
1.1 |
*/ |
189 |
|
|
public int size() { |
190 |
|
|
return m.size(); |
191 |
|
|
} |
192 |
|
|
|
193 |
|
|
/** |
194 |
dl |
1.21 |
* Returns {@code true} if this set contains no elements. |
195 |
dl |
1.1 |
* |
196 |
dl |
1.21 |
* @return {@code true} if this set contains no elements |
197 |
dl |
1.1 |
*/ |
198 |
|
|
public boolean isEmpty() { |
199 |
|
|
return m.isEmpty(); |
200 |
|
|
} |
201 |
|
|
|
202 |
|
|
/** |
203 |
dl |
1.21 |
* Returns {@code true} if this set contains the specified element. |
204 |
|
|
* More formally, returns {@code true} if and only if this set |
205 |
|
|
* contains an element {@code e} such that |
206 |
|
|
* {@code (o==null ? e==null : o.equals(e))}. |
207 |
dl |
1.1 |
* |
208 |
jsr166 |
1.16 |
* @param o object to be checked for containment in this set |
209 |
dl |
1.21 |
* @return {@code true} if this set contains the specified element |
210 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
211 |
jsr166 |
1.11 |
* with the elements currently in the set |
212 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
213 |
|
|
* and this set uses natural ordering, or its comparator |
214 |
|
|
* does not permit null elements |
215 |
dl |
1.1 |
*/ |
216 |
|
|
public boolean contains(Object o) { |
217 |
|
|
return m.containsKey(o); |
218 |
|
|
} |
219 |
|
|
|
220 |
|
|
/** |
221 |
|
|
* Adds the specified element to this set if it is not already present. |
222 |
dl |
1.21 |
* More formally, adds the specified element {@code e} to this set if |
223 |
|
|
* the set contains no element {@code e2} such that |
224 |
|
|
* {@code (e==null ? e2==null : e.equals(e2))}. |
225 |
jsr166 |
1.16 |
* If this set already contains the element, the call leaves the set |
226 |
dl |
1.21 |
* unchanged and returns {@code false}. |
227 |
dl |
1.1 |
* |
228 |
jsr166 |
1.11 |
* @param e element to be added to this set |
229 |
dl |
1.21 |
* @return {@code true} if this set did not already contain the specified |
230 |
jsr166 |
1.11 |
* element |
231 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
232 |
jsr166 |
1.16 |
* with the elements currently in this set |
233 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
234 |
|
|
* and this set uses natural ordering, or its comparator |
235 |
|
|
* does not permit null elements |
236 |
dl |
1.1 |
*/ |
237 |
jsr166 |
1.7 |
public boolean add(E e) { |
238 |
|
|
return m.put(e, PRESENT)==null; |
239 |
dl |
1.1 |
} |
240 |
|
|
|
241 |
|
|
/** |
242 |
|
|
* Removes the specified element from this set if it is present. |
243 |
dl |
1.21 |
* More formally, removes an element {@code e} such that |
244 |
|
|
* {@code (o==null ? e==null : o.equals(e))}, |
245 |
|
|
* if this set contains such an element. Returns {@code true} if |
246 |
jsr166 |
1.16 |
* this set contained the element (or equivalently, if this set |
247 |
|
|
* changed as a result of the call). (This set will not contain the |
248 |
|
|
* element once the call returns.) |
249 |
dl |
1.1 |
* |
250 |
jsr166 |
1.11 |
* @param o object to be removed from this set, if present |
251 |
dl |
1.21 |
* @return {@code true} if this set contained the specified element |
252 |
dl |
1.1 |
* @throws ClassCastException if the specified object cannot be compared |
253 |
jsr166 |
1.16 |
* with the elements currently in this set |
254 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
255 |
|
|
* and this set uses natural ordering, or its comparator |
256 |
|
|
* does not permit null elements |
257 |
dl |
1.1 |
*/ |
258 |
|
|
public boolean remove(Object o) { |
259 |
|
|
return m.remove(o)==PRESENT; |
260 |
|
|
} |
261 |
|
|
|
262 |
|
|
/** |
263 |
|
|
* Removes all of the elements from this set. |
264 |
jsr166 |
1.11 |
* The set will be empty after this call returns. |
265 |
dl |
1.1 |
*/ |
266 |
|
|
public void clear() { |
267 |
|
|
m.clear(); |
268 |
|
|
} |
269 |
|
|
|
270 |
|
|
/** |
271 |
|
|
* Adds all of the elements in the specified collection to this set. |
272 |
|
|
* |
273 |
jsr166 |
1.14 |
* @param c collection containing elements to be added to this set |
274 |
dl |
1.21 |
* @return {@code true} if this set changed as a result of the call |
275 |
dl |
1.1 |
* @throws ClassCastException if the elements provided cannot be compared |
276 |
jsr166 |
1.11 |
* with the elements currently in the set |
277 |
|
|
* @throws NullPointerException if the specified collection is null or |
278 |
|
|
* if any element is null and this set uses natural ordering, or |
279 |
|
|
* its comparator does not permit null elements |
280 |
dl |
1.1 |
*/ |
281 |
|
|
public boolean addAll(Collection<? extends E> c) { |
282 |
|
|
// Use linear-time version if applicable |
283 |
|
|
if (m.size()==0 && c.size() > 0 && |
284 |
|
|
c instanceof SortedSet && |
285 |
|
|
m instanceof TreeMap) { |
286 |
jsr166 |
1.9 |
SortedSet<? extends E> set = (SortedSet<? extends E>) c; |
287 |
dl |
1.1 |
TreeMap<E,Object> map = (TreeMap<E, Object>) m; |
288 |
jsr166 |
1.9 |
Comparator<? super E> cc = (Comparator<? super E>) set.comparator(); |
289 |
dl |
1.1 |
Comparator<? super E> mc = map.comparator(); |
290 |
|
|
if (cc==mc || (cc != null && cc.equals(mc))) { |
291 |
|
|
map.addAllForTreeSet(set, PRESENT); |
292 |
|
|
return true; |
293 |
|
|
} |
294 |
|
|
} |
295 |
|
|
return super.addAll(c); |
296 |
|
|
} |
297 |
|
|
|
298 |
|
|
/** |
299 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
300 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} or {@code toElement} |
301 |
|
|
* is null and this set uses natural ordering, or its comparator |
302 |
|
|
* does not permit null elements |
303 |
jsr166 |
1.11 |
* @throws IllegalArgumentException {@inheritDoc} |
304 |
jsr166 |
1.17 |
* @since 1.6 |
305 |
dl |
1.1 |
*/ |
306 |
dl |
1.22 |
public NavigableSet<E> subSet(E fromElement, boolean fromInclusive, |
307 |
|
|
E toElement, boolean toInclusive) { |
308 |
|
|
return new TreeSet<E>(m.subMap(fromElement, fromInclusive, |
309 |
|
|
toElement, toInclusive)); |
310 |
dl |
1.1 |
} |
311 |
|
|
|
312 |
|
|
/** |
313 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
314 |
dl |
1.21 |
* @throws NullPointerException if {@code toElement} is null and |
315 |
jsr166 |
1.11 |
* this set uses natural ordering, or its comparator does |
316 |
|
|
* not permit null elements |
317 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
318 |
jsr166 |
1.17 |
* @since 1.6 |
319 |
dl |
1.1 |
*/ |
320 |
dl |
1.22 |
public NavigableSet<E> headSet(E toElement, boolean inclusive) { |
321 |
|
|
return new TreeSet<E>(m.headMap(toElement, inclusive)); |
322 |
dl |
1.1 |
} |
323 |
|
|
|
324 |
|
|
/** |
325 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
326 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} is null and |
327 |
jsr166 |
1.11 |
* this set uses natural ordering, or its comparator does |
328 |
|
|
* not permit null elements |
329 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
330 |
jsr166 |
1.17 |
* @since 1.6 |
331 |
dl |
1.1 |
*/ |
332 |
dl |
1.22 |
public NavigableSet<E> tailSet(E fromElement, boolean inclusive) { |
333 |
|
|
return new TreeSet<E>(m.tailMap(fromElement, inclusive)); |
334 |
dl |
1.3 |
} |
335 |
|
|
|
336 |
|
|
/** |
337 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
338 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} or |
339 |
|
|
* {@code toElement} is null and this set uses natural ordering, |
340 |
jsr166 |
1.11 |
* or its comparator does not permit null elements |
341 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
342 |
dl |
1.3 |
*/ |
343 |
|
|
public SortedSet<E> subSet(E fromElement, E toElement) { |
344 |
dl |
1.22 |
return subSet(fromElement, true, toElement, false); |
345 |
dl |
1.3 |
} |
346 |
|
|
|
347 |
|
|
/** |
348 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
349 |
dl |
1.21 |
* @throws NullPointerException if {@code toElement} is null |
350 |
jsr166 |
1.11 |
* 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 |
dl |
1.22 |
return headSet(toElement, false); |
356 |
dl |
1.3 |
} |
357 |
|
|
|
358 |
|
|
/** |
359 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
360 |
dl |
1.21 |
* @throws NullPointerException if {@code fromElement} is null |
361 |
jsr166 |
1.11 |
* and this set uses natural ordering, or its comparator does |
362 |
|
|
* not permit null elements |
363 |
|
|
* @throws IllegalArgumentException {@inheritDoc} |
364 |
dl |
1.3 |
*/ |
365 |
|
|
public SortedSet<E> tailSet(E fromElement) { |
366 |
dl |
1.22 |
return tailSet(fromElement, true); |
367 |
dl |
1.1 |
} |
368 |
|
|
|
369 |
|
|
public Comparator<? super E> comparator() { |
370 |
|
|
return m.comparator(); |
371 |
|
|
} |
372 |
|
|
|
373 |
|
|
/** |
374 |
jsr166 |
1.11 |
* @throws NoSuchElementException {@inheritDoc} |
375 |
dl |
1.1 |
*/ |
376 |
|
|
public E first() { |
377 |
|
|
return m.firstKey(); |
378 |
|
|
} |
379 |
|
|
|
380 |
|
|
/** |
381 |
jsr166 |
1.11 |
* @throws NoSuchElementException {@inheritDoc} |
382 |
dl |
1.1 |
*/ |
383 |
|
|
public E last() { |
384 |
|
|
return m.lastKey(); |
385 |
|
|
} |
386 |
|
|
|
387 |
|
|
// NavigableSet API methods |
388 |
|
|
|
389 |
|
|
/** |
390 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
391 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
392 |
|
|
* and this set uses natural ordering, or its comparator |
393 |
|
|
* does not permit null elements |
394 |
jsr166 |
1.17 |
* @since 1.6 |
395 |
dl |
1.1 |
*/ |
396 |
jsr166 |
1.11 |
public E lower(E e) { |
397 |
|
|
return m.lowerKey(e); |
398 |
dl |
1.1 |
} |
399 |
|
|
|
400 |
|
|
/** |
401 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
402 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
403 |
|
|
* and this set uses natural ordering, or its comparator |
404 |
|
|
* does not permit null elements |
405 |
jsr166 |
1.17 |
* @since 1.6 |
406 |
dl |
1.1 |
*/ |
407 |
jsr166 |
1.11 |
public E floor(E e) { |
408 |
|
|
return m.floorKey(e); |
409 |
dl |
1.1 |
} |
410 |
|
|
|
411 |
|
|
/** |
412 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
413 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
414 |
|
|
* and this set uses natural ordering, or its comparator |
415 |
|
|
* does not permit null elements |
416 |
jsr166 |
1.17 |
* @since 1.6 |
417 |
dl |
1.1 |
*/ |
418 |
jsr166 |
1.11 |
public E ceiling(E e) { |
419 |
|
|
return m.ceilingKey(e); |
420 |
dl |
1.1 |
} |
421 |
|
|
|
422 |
|
|
/** |
423 |
jsr166 |
1.11 |
* @throws ClassCastException {@inheritDoc} |
424 |
jsr166 |
1.15 |
* @throws NullPointerException if the specified element is null |
425 |
|
|
* and this set uses natural ordering, or its comparator |
426 |
|
|
* does not permit null elements |
427 |
jsr166 |
1.17 |
* @since 1.6 |
428 |
dl |
1.1 |
*/ |
429 |
jsr166 |
1.7 |
public E higher(E e) { |
430 |
|
|
return m.higherKey(e); |
431 |
dl |
1.1 |
} |
432 |
|
|
|
433 |
jsr166 |
1.17 |
/** |
434 |
|
|
* @since 1.6 |
435 |
|
|
*/ |
436 |
dl |
1.1 |
public E pollFirst() { |
437 |
|
|
Map.Entry<E,?> e = m.pollFirstEntry(); |
438 |
|
|
return (e == null)? null : e.getKey(); |
439 |
|
|
} |
440 |
|
|
|
441 |
jsr166 |
1.17 |
/** |
442 |
|
|
* @since 1.6 |
443 |
|
|
*/ |
444 |
dl |
1.1 |
public E pollLast() { |
445 |
|
|
Map.Entry<E,?> e = m.pollLastEntry(); |
446 |
|
|
return (e == null)? null : e.getKey(); |
447 |
|
|
} |
448 |
|
|
|
449 |
|
|
/** |
450 |
dl |
1.21 |
* Returns a shallow copy of this {@code TreeSet} instance. (The elements |
451 |
dl |
1.1 |
* themselves are not cloned.) |
452 |
|
|
* |
453 |
jsr166 |
1.11 |
* @return a shallow copy of this set |
454 |
dl |
1.1 |
*/ |
455 |
|
|
public Object clone() { |
456 |
|
|
TreeSet<E> clone = null; |
457 |
|
|
try { |
458 |
|
|
clone = (TreeSet<E>) super.clone(); |
459 |
|
|
} catch (CloneNotSupportedException e) { |
460 |
|
|
throw new InternalError(); |
461 |
|
|
} |
462 |
|
|
|
463 |
|
|
clone.m = new TreeMap<E,Object>(m); |
464 |
|
|
return clone; |
465 |
|
|
} |
466 |
|
|
|
467 |
|
|
/** |
468 |
dl |
1.21 |
* Save the state of the {@code TreeSet} instance to a stream (that is, |
469 |
dl |
1.1 |
* serialize it). |
470 |
|
|
* |
471 |
|
|
* @serialData Emits the comparator used to order this set, or |
472 |
dl |
1.21 |
* {@code null} if it obeys its elements' natural ordering |
473 |
jsr166 |
1.11 |
* (Object), followed by the size of the set (the number of |
474 |
|
|
* elements it contains) (int), followed by all of its |
475 |
|
|
* elements (each an Object) in order (as determined by the |
476 |
|
|
* set's Comparator, or by the elements' natural ordering if |
477 |
dl |
1.1 |
* the set has no Comparator). |
478 |
|
|
*/ |
479 |
|
|
private void writeObject(java.io.ObjectOutputStream s) |
480 |
|
|
throws java.io.IOException { |
481 |
|
|
// Write out any hidden stuff |
482 |
|
|
s.defaultWriteObject(); |
483 |
|
|
|
484 |
|
|
// Write out Comparator |
485 |
|
|
s.writeObject(m.comparator()); |
486 |
|
|
|
487 |
|
|
// Write out size |
488 |
|
|
s.writeInt(m.size()); |
489 |
|
|
|
490 |
|
|
// Write out all elements in the proper order. |
491 |
|
|
for (Iterator i=m.keySet().iterator(); i.hasNext(); ) |
492 |
|
|
s.writeObject(i.next()); |
493 |
|
|
} |
494 |
|
|
|
495 |
|
|
/** |
496 |
dl |
1.21 |
* Reconstitute the {@code TreeSet} instance from a stream (that is, |
497 |
dl |
1.1 |
* deserialize it). |
498 |
|
|
*/ |
499 |
|
|
private void readObject(java.io.ObjectInputStream s) |
500 |
|
|
throws java.io.IOException, ClassNotFoundException { |
501 |
|
|
// Read in any hidden stuff |
502 |
|
|
s.defaultReadObject(); |
503 |
|
|
|
504 |
|
|
// Read in Comparator |
505 |
jsr166 |
1.9 |
Comparator<? super E> c = (Comparator<? super E>) s.readObject(); |
506 |
dl |
1.1 |
|
507 |
|
|
// Create backing TreeMap |
508 |
|
|
TreeMap<E,Object> tm; |
509 |
|
|
if (c==null) |
510 |
|
|
tm = new TreeMap<E,Object>(); |
511 |
|
|
else |
512 |
|
|
tm = new TreeMap<E,Object>(c); |
513 |
|
|
m = tm; |
514 |
|
|
|
515 |
|
|
// Read in size |
516 |
|
|
int size = s.readInt(); |
517 |
|
|
|
518 |
|
|
tm.readTreeSet(size, s, PRESENT); |
519 |
|
|
} |
520 |
|
|
|
521 |
|
|
private static final long serialVersionUID = -2479143000061671589L; |
522 |
|
|
} |