| /* |
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| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
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| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
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| |
| package java.util; |
| |
| /** |
| * A {@link Map} that further provides a <em>total ordering</em> on its keys. |
| * The map is ordered according to the {@linkplain Comparable natural |
| * ordering} of its keys, or by a {@link Comparator} typically |
| * provided at sorted map creation time. This order is reflected when |
| * iterating over the sorted map's collection views (returned by the |
| * {@code entrySet}, {@code keySet} and {@code values} methods). |
| * Several additional operations are provided to take advantage of the |
| * ordering. (This interface is the map analogue of {@link SortedSet}.) |
| * |
| * <p>All keys inserted into a sorted map must implement the {@code Comparable} |
| * interface (or be accepted by the specified comparator). Furthermore, all |
| * such keys must be <em>mutually comparable</em>: {@code k1.compareTo(k2)} (or |
| * {@code comparator.compare(k1, k2)}) must not throw a |
| * {@code ClassCastException} for any keys {@code k1} and {@code k2} in |
| * the sorted map. Attempts to violate this restriction will cause the |
| * offending method or constructor invocation to throw a |
| * {@code ClassCastException}. |
| * |
| * <p>Note that the ordering maintained by a sorted map (whether or not an |
| * explicit comparator is provided) must be <em>consistent with equals</em> if |
| * the sorted map is to correctly implement the {@code Map} interface. (See |
| * the {@code Comparable} interface or {@code Comparator} interface for a |
| * precise definition of <em>consistent with equals</em>.) This is so because |
| * the {@code Map} interface is defined in terms of the {@code equals} |
| * operation, but a sorted map performs all key comparisons using its |
| * {@code compareTo} (or {@code compare}) method, so two keys that are |
| * deemed equal by this method are, from the standpoint of the sorted map, |
| * equal. The behavior of a tree map <em>is</em> well-defined even if its |
| * ordering is inconsistent with equals; it just fails to obey the general |
| * contract of the {@code Map} interface. |
| * |
| * <p>All general-purpose sorted map implementation classes should provide four |
| * "standard" constructors. It is not possible to enforce this recommendation |
| * though as required constructors cannot be specified by interfaces. The |
| * expected "standard" constructors for all sorted map implementations are: |
| * <ol> |
| * <li>A void (no arguments) constructor, which creates an empty sorted map |
| * sorted according to the natural ordering of its keys.</li> |
| * <li>A constructor with a single argument of type {@code Comparator}, which |
| * creates an empty sorted map sorted according to the specified comparator.</li> |
| * <li>A constructor with a single argument of type {@code Map}, which creates |
| * a new map with the same key-value mappings as its argument, sorted |
| * according to the keys' natural ordering.</li> |
| * <li>A constructor with a single argument of type {@code SortedMap}, which |
| * creates a new sorted map with the same key-value mappings and the same |
| * ordering as the input sorted map.</li> |
| * </ol> |
| * |
| * <p><strong>Note</strong>: several methods return submaps with restricted key |
| * ranges. Such ranges are <em>half-open</em>, that is, they include their low |
| * endpoint but not their high endpoint (where applicable). If you need a |
| * <em>closed range</em> (which includes both endpoints), and the key type |
| * allows for calculation of the successor of a given key, merely request |
| * the subrange from {@code lowEndpoint} to |
| * {@code successor(highEndpoint)}. For example, suppose that {@code m} |
| * is a map whose keys are strings. The following idiom obtains a view |
| * containing all of the key-value mappings in {@code m} whose keys are |
| * between {@code low} and {@code high}, inclusive:<pre> |
| * SortedMap<String, V> sub = m.subMap(low, high+"\0");</pre> |
| * |
| * A similar technique can be used to generate an <em>open range</em> |
| * (which contains neither endpoint). The following idiom obtains a |
| * view containing all of the key-value mappings in {@code m} whose keys |
| * are between {@code low} and {@code high}, exclusive:<pre> |
| * SortedMap<String, V> sub = m.subMap(low+"\0", high);</pre> |
| * |
| * <p>This interface is a member of the |
| * <a href="{@docRoot}/../technotes/guides/collections/index.html"> |
| * Java Collections Framework</a>. |
| * |
| * @param <K> the type of keys maintained by this map |
| * @param <V> the type of mapped values |
| * |
| * @author Josh Bloch |
| * @see Map |
| * @see TreeMap |
| * @see SortedSet |
| * @see Comparator |
| * @see Comparable |
| * @see Collection |
| * @see ClassCastException |
| * @since 1.2 |
| */ |
| |
| public interface SortedMap<K,V> extends Map<K,V> { |
| /** |
| * Returns the comparator used to order the keys in this map, or |
| * {@code null} if this map uses the {@linkplain Comparable |
| * natural ordering} of its keys. |
| * |
| * @return the comparator used to order the keys in this map, |
| * or {@code null} if this map uses the natural ordering |
| * of its keys |
| */ |
| Comparator<? super K> comparator(); |
| |
| /** |
| * Returns a view of the portion of this map whose keys range from |
| * {@code fromKey}, inclusive, to {@code toKey}, exclusive. (If |
| * {@code fromKey} and {@code toKey} are equal, the returned map |
| * is empty.) The returned map is backed by this map, so changes |
| * in the returned map are reflected in this map, and vice-versa. |
| * The returned map supports all optional map operations that this |
| * map supports. |
| * |
| * <p>The returned map will throw an {@code IllegalArgumentException} |
| * on an attempt to insert a key outside its range. |
| * |
| * @param fromKey low endpoint (inclusive) of the keys in the returned map |
| * @param toKey high endpoint (exclusive) of the keys in the returned map |
| * @return a view of the portion of this map whose keys range from |
| * {@code fromKey}, inclusive, to {@code toKey}, exclusive |
| * @throws ClassCastException if {@code fromKey} and {@code toKey} |
| * cannot be compared to one another using this map's comparator |
| * (or, if the map has no comparator, using natural ordering). |
| * Implementations may, but are not required to, throw this |
| * exception if {@code fromKey} or {@code toKey} |
| * cannot be compared to keys currently in the map. |
| * @throws NullPointerException if {@code fromKey} or {@code toKey} |
| * is null and this map does not permit null keys |
| * @throws IllegalArgumentException if {@code fromKey} is greater than |
| * {@code toKey}; or if this map itself has a restricted |
| * range, and {@code fromKey} or {@code toKey} lies |
| * outside the bounds of the range |
| */ |
| SortedMap<K,V> subMap(K fromKey, K toKey); |
| |
| /** |
| * Returns a view of the portion of this map whose keys are |
| * strictly less than {@code toKey}. The returned map is backed |
| * by this map, so changes in the returned map are reflected in |
| * this map, and vice-versa. The returned map supports all |
| * optional map operations that this map supports. |
| * |
| * <p>The returned map will throw an {@code IllegalArgumentException} |
| * on an attempt to insert a key outside its range. |
| * |
| * @param toKey high endpoint (exclusive) of the keys in the returned map |
| * @return a view of the portion of this map whose keys are strictly |
| * less than {@code toKey} |
| * @throws ClassCastException if {@code toKey} is not compatible |
| * with this map's comparator (or, if the map has no comparator, |
| * if {@code toKey} does not implement {@link Comparable}). |
| * Implementations may, but are not required to, throw this |
| * exception if {@code toKey} cannot be compared to keys |
| * currently in the map. |
| * @throws NullPointerException if {@code toKey} is null and |
| * this map does not permit null keys |
| * @throws IllegalArgumentException if this map itself has a |
| * restricted range, and {@code toKey} lies outside the |
| * bounds of the range |
| */ |
| SortedMap<K,V> headMap(K toKey); |
| |
| /** |
| * Returns a view of the portion of this map whose keys are |
| * greater than or equal to {@code fromKey}. The returned map is |
| * backed by this map, so changes in the returned map are |
| * reflected in this map, and vice-versa. The returned map |
| * supports all optional map operations that this map supports. |
| * |
| * <p>The returned map will throw an {@code IllegalArgumentException} |
| * on an attempt to insert a key outside its range. |
| * |
| * @param fromKey low endpoint (inclusive) of the keys in the returned map |
| * @return a view of the portion of this map whose keys are greater |
| * than or equal to {@code fromKey} |
| * @throws ClassCastException if {@code fromKey} is not compatible |
| * with this map's comparator (or, if the map has no comparator, |
| * if {@code fromKey} does not implement {@link Comparable}). |
| * Implementations may, but are not required to, throw this |
| * exception if {@code fromKey} cannot be compared to keys |
| * currently in the map. |
| * @throws NullPointerException if {@code fromKey} is null and |
| * this map does not permit null keys |
| * @throws IllegalArgumentException if this map itself has a |
| * restricted range, and {@code fromKey} lies outside the |
| * bounds of the range |
| */ |
| SortedMap<K,V> tailMap(K fromKey); |
| |
| /** |
| * Returns the first (lowest) key currently in this map. |
| * |
| * @return the first (lowest) key currently in this map |
| * @throws NoSuchElementException if this map is empty |
| */ |
| K firstKey(); |
| |
| /** |
| * Returns the last (highest) key currently in this map. |
| * |
| * @return the last (highest) key currently in this map |
| * @throws NoSuchElementException if this map is empty |
| */ |
| K lastKey(); |
| |
| /** |
| * Returns a {@link Set} view of the keys contained in this map. |
| * The set's iterator returns the keys in ascending order. |
| * The set is backed by the map, so changes to the map are |
| * reflected in the set, and vice-versa. If the map is modified |
| * while an iteration over the set is in progress (except through |
| * the iterator's own {@code remove} operation), the results of |
| * the iteration are undefined. The set supports element removal, |
| * which removes the corresponding mapping from the map, via the |
| * {@code Iterator.remove}, {@code Set.remove}, |
| * {@code removeAll}, {@code retainAll}, and {@code clear} |
| * operations. It does not support the {@code add} or {@code addAll} |
| * operations. |
| * |
| * @return a set view of the keys contained in this map, sorted in |
| * ascending order |
| */ |
| Set<K> keySet(); |
| |
| /** |
| * Returns a {@link Collection} view of the values contained in this map. |
| * The collection's iterator returns the values in ascending order |
| * of the corresponding keys. |
| * The collection is backed by the map, so changes to the map are |
| * reflected in the collection, and vice-versa. If the map is |
| * modified while an iteration over the collection is in progress |
| * (except through the iterator's own {@code remove} operation), |
| * the results of the iteration are undefined. The collection |
| * supports element removal, which removes the corresponding |
| * mapping from the map, via the {@code Iterator.remove}, |
| * {@code Collection.remove}, {@code removeAll}, |
| * {@code retainAll} and {@code clear} operations. It does not |
| * support the {@code add} or {@code addAll} operations. |
| * |
| * @return a collection view of the values contained in this map, |
| * sorted in ascending key order |
| */ |
| Collection<V> values(); |
| |
| /** |
| * Returns a {@link Set} view of the mappings contained in this map. |
| * The set's iterator returns the entries in ascending key order. |
| * The set is backed by the map, so changes to the map are |
| * reflected in the set, and vice-versa. If the map is modified |
| * while an iteration over the set is in progress (except through |
| * the iterator's own {@code remove} operation, or through the |
| * {@code setValue} operation on a map entry returned by the |
| * iterator) the results of the iteration are undefined. The set |
| * supports element removal, which removes the corresponding |
| * mapping from the map, via the {@code Iterator.remove}, |
| * {@code Set.remove}, {@code removeAll}, {@code retainAll} and |
| * {@code clear} operations. It does not support the |
| * {@code add} or {@code addAll} operations. |
| * |
| * @return a set view of the mappings contained in this map, |
| * sorted in ascending key order |
| */ |
| Set<Map.Entry<K, V>> entrySet(); |
| } |
