001/*
002 * Copyright (C) 2011 The Guava Authors
003 *
004 * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
005 * in compliance with the License. You may obtain a copy of the License at
006 *
007 * http://www.apache.org/licenses/LICENSE-2.0
008 *
009 * Unless required by applicable law or agreed to in writing, software distributed under the
010 * License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either
011 * express or implied. See the License for the specific language governing permissions and
012 * limitations under the License.
013 */
014
015package com.google.common.collect;
016
017import com.google.common.annotations.Beta;
018import com.google.common.annotations.GwtIncompatible;
019import java.util.NoSuchElementException;
020import java.util.Set;
021import org.checkerframework.checker.nullness.compatqual.NullableDecl;
022
023/**
024 * A set comprising zero or more {@linkplain Range#isEmpty nonempty}, {@linkplain
025 * Range#isConnected(Range) disconnected} ranges of type {@code C}.
026 *
027 * <p>Implementations that choose to support the {@link #add(Range)} operation are required to
028 * ignore empty ranges and coalesce connected ranges. For example:
029 *
030 * <pre>{@code
031 * RangeSet<Integer> rangeSet = TreeRangeSet.create();
032 * rangeSet.add(Range.closed(1, 10)); // {[1, 10]}
033 * rangeSet.add(Range.closedOpen(11, 15)); // disconnected range; {[1, 10], [11, 15)}
034 * rangeSet.add(Range.closedOpen(15, 20)); // connected range; {[1, 10], [11, 20)}
035 * rangeSet.add(Range.openClosed(0, 0)); // empty range; {[1, 10], [11, 20)}
036 * rangeSet.remove(Range.open(5, 10)); // splits [1, 10]; {[1, 5], [10, 10], [11, 20)}
037 * }</pre>
038 *
039 * <p>Note that the behavior of {@link Range#isEmpty()} and {@link Range#isConnected(Range)} may not
040 * be as expected on discrete ranges. See the Javadoc of those methods for details.
041 *
042 * <p>For a {@link Set} whose contents are specified by a {@link Range}, see {@link ContiguousSet}.
043 *
044 * <p>See the Guava User Guide article on <a href=
045 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#rangeset"> RangeSets</a>.
046 *
047 * @author Kevin Bourrillion
048 * @author Louis Wasserman
049 * @since 14.0
050 */
051@Beta
052@GwtIncompatible
053public interface RangeSet<C extends Comparable> {
054
055  // Query methods
056
057  /** Determines whether any of this range set's member ranges contains {@code value}. */
058  boolean contains(C value);
059
060  /**
061   * Returns the unique range from this range set that {@linkplain Range#contains contains} {@code
062   * value}, or {@code null} if this range set does not contain {@code value}.
063   */
064  Range<C> rangeContaining(C value);
065
066  /**
067   * Returns {@code true} if there exists a non-empty range enclosed by both a member range in this
068   * range set and the specified range. This is equivalent to calling {@code
069   * subRangeSet(otherRange)} and testing whether the resulting range set is non-empty.
070   *
071   * @since 20.0
072   */
073  boolean intersects(Range<C> otherRange);
074
075  /**
076   * Returns {@code true} if there exists a member range in this range set which {@linkplain
077   * Range#encloses encloses} the specified range.
078   */
079  boolean encloses(Range<C> otherRange);
080
081  /**
082   * Returns {@code true} if for each member range in {@code other} there exists a member range in
083   * this range set which {@linkplain Range#encloses encloses} it. It follows that {@code
084   * this.contains(value)} whenever {@code other.contains(value)}. Returns {@code true} if {@code
085   * other} is empty.
086   *
087   * <p>This is equivalent to checking if this range set {@link #encloses} each of the ranges in
088   * {@code other}.
089   */
090  boolean enclosesAll(RangeSet<C> other);
091
092  /**
093   * Returns {@code true} if for each range in {@code other} there exists a member range in this
094   * range set which {@linkplain Range#encloses encloses} it. Returns {@code true} if {@code other}
095   * is empty.
096   *
097   * <p>This is equivalent to checking if this range set {@link #encloses} each range in {@code
098   * other}.
099   *
100   * @since 21.0
101   */
102  boolean enclosesAll(Iterable<Range<C>> other);
103
104  /** Returns {@code true} if this range set contains no ranges. */
105  boolean isEmpty();
106
107  /**
108   * Returns the minimal range which {@linkplain Range#encloses(Range) encloses} all ranges in this
109   * range set.
110   *
111   * @throws NoSuchElementException if this range set is {@linkplain #isEmpty() empty}
112   */
113  Range<C> span();
114
115  // Views
116
117  /**
118   * Returns a view of the {@linkplain Range#isConnected disconnected} ranges that make up this
119   * range set. The returned set may be empty. The iterators returned by its {@link
120   * Iterable#iterator} method return the ranges in increasing order of lower bound (equivalently,
121   * of upper bound).
122   */
123  Set<Range<C>> asRanges();
124
125  /**
126   * Returns a descending view of the {@linkplain Range#isConnected disconnected} ranges that make
127   * up this range set. The returned set may be empty. The iterators returned by its {@link
128   * Iterable#iterator} method return the ranges in decreasing order of lower bound (equivalently,
129   * of upper bound).
130   *
131   * @since 19.0
132   */
133  Set<Range<C>> asDescendingSetOfRanges();
134
135  /**
136   * Returns a view of the complement of this {@code RangeSet}.
137   *
138   * <p>The returned view supports the {@link #add} operation if this {@code RangeSet} supports
139   * {@link #remove}, and vice versa.
140   */
141  RangeSet<C> complement();
142
143  /**
144   * Returns a view of the intersection of this {@code RangeSet} with the specified range.
145   *
146   * <p>The returned view supports all optional operations supported by this {@code RangeSet}, with
147   * the caveat that an {@link IllegalArgumentException} is thrown on an attempt to {@linkplain
148   * #add(Range) add} any range not {@linkplain Range#encloses(Range) enclosed} by {@code view}.
149   */
150  RangeSet<C> subRangeSet(Range<C> view);
151
152  // Modification
153
154  /**
155   * Adds the specified range to this {@code RangeSet} (optional operation). That is, for equal
156   * range sets a and b, the result of {@code a.add(range)} is that {@code a} will be the minimal
157   * range set for which both {@code a.enclosesAll(b)} and {@code a.encloses(range)}.
158   *
159   * <p>Note that {@code range} will be {@linkplain Range#span(Range) coalesced} with any ranges in
160   * the range set that are {@linkplain Range#isConnected(Range) connected} with it. Moreover, if
161   * {@code range} is empty, this is a no-op.
162   *
163   * @throws UnsupportedOperationException if this range set does not support the {@code add}
164   *     operation
165   */
166  void add(Range<C> range);
167
168  /**
169   * Removes the specified range from this {@code RangeSet} (optional operation). After this
170   * operation, if {@code range.contains(c)}, {@code this.contains(c)} will return {@code false}.
171   *
172   * <p>If {@code range} is empty, this is a no-op.
173   *
174   * @throws UnsupportedOperationException if this range set does not support the {@code remove}
175   *     operation
176   */
177  void remove(Range<C> range);
178
179  /**
180   * Removes all ranges from this {@code RangeSet} (optional operation). After this operation,
181   * {@code this.contains(c)} will return false for all {@code c}.
182   *
183   * <p>This is equivalent to {@code remove(Range.all())}.
184   *
185   * @throws UnsupportedOperationException if this range set does not support the {@code clear}
186   *     operation
187   */
188  void clear();
189
190  /**
191   * Adds all of the ranges from the specified range set to this range set (optional operation).
192   * After this operation, this range set is the minimal range set that {@linkplain
193   * #enclosesAll(RangeSet) encloses} both the original range set and {@code other}.
194   *
195   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
196   *
197   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
198   *     operation
199   */
200  void addAll(RangeSet<C> other);
201
202  /**
203   * Adds all of the specified ranges to this range set (optional operation). After this operation,
204   * this range set is the minimal range set that {@linkplain #enclosesAll(RangeSet) encloses} both
205   * the original range set and each range in {@code other}.
206   *
207   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
208   *
209   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
210   *     operation
211   * @since 21.0
212   */
213  void addAll(Iterable<Range<C>> ranges);
214
215  /**
216   * Removes all of the ranges from the specified range set from this range set (optional
217   * operation). After this operation, if {@code other.contains(c)}, {@code this.contains(c)} will
218   * return {@code false}.
219   *
220   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
221   * turn.
222   *
223   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
224   *     operation
225   */
226  void removeAll(RangeSet<C> other);
227
228  /**
229   * Removes all of the specified ranges from this range set (optional operation).
230   *
231   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
232   * turn.
233   *
234   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
235   *     operation
236   * @since 21.0
237   */
238  void removeAll(Iterable<Range<C>> ranges);
239
240  // Object methods
241
242  /**
243   * Returns {@code true} if {@code obj} is another {@code RangeSet} that contains the same ranges
244   * according to {@link Range#equals(Object)}.
245   */
246  @Override
247  boolean equals(@NullableDecl Object obj);
248
249  /** Returns {@code asRanges().hashCode()}. */
250  @Override
251  int hashCode();
252
253  /**
254   * Returns a readable string representation of this range set. For example, if this {@code
255   * RangeSet} consisted of {@code Range.closed(1, 3)} and {@code Range.greaterThan(4)}, this might
256   * return {@code " [1..3](4..+∞)}"}.
257   */
258  @Override
259  String toString();
260}