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 com.google.errorprone.annotations.DoNotMock;
020import java.util.NoSuchElementException;
021import java.util.Set;
022import org.checkerframework.checker.nullness.compatqual.NullableDecl;
023
024/**
025 * A set comprising zero or more {@linkplain Range#isEmpty nonempty}, {@linkplain
026 * Range#isConnected(Range) disconnected} ranges of type {@code C}.
027 *
028 * <p>Implementations that choose to support the {@link #add(Range)} operation are required to
029 * ignore empty ranges and coalesce connected ranges. For example:
030 *
031 * <pre>{@code
032 * RangeSet<Integer> rangeSet = TreeRangeSet.create();
033 * rangeSet.add(Range.closed(1, 10)); // {[1, 10]}
034 * rangeSet.add(Range.closedOpen(11, 15)); // disconnected range; {[1, 10], [11, 15)}
035 * rangeSet.add(Range.closedOpen(15, 20)); // connected range; {[1, 10], [11, 20)}
036 * rangeSet.add(Range.openClosed(0, 0)); // empty range; {[1, 10], [11, 20)}
037 * rangeSet.remove(Range.open(5, 10)); // splits [1, 10]; {[1, 5], [10, 10], [11, 20)}
038 * }</pre>
039 *
040 * <p>Note that the behavior of {@link Range#isEmpty()} and {@link Range#isConnected(Range)} may not
041 * be as expected on discrete ranges. See the Javadoc of those methods for details.
042 *
043 * <p>For a {@link Set} whose contents are specified by a {@link Range}, see {@link ContiguousSet}.
044 *
045 * <p>See the Guava User Guide article on <a href=
046 * "https://github.com/google/guava/wiki/NewCollectionTypesExplained#rangeset"> RangeSets</a>.
047 *
048 * @author Kevin Bourrillion
049 * @author Louis Wasserman
050 * @since 14.0
051 */
052@Beta
053@DoNotMock("Use ImmutableRangeSet or TreeRangeSet")
054@GwtIncompatible
055public interface RangeSet<C extends Comparable> {
056
057  // Query methods
058
059  /** Determines whether any of this range set's member ranges contains {@code value}. */
060  boolean contains(C value);
061
062  /**
063   * Returns the unique range from this range set that {@linkplain Range#contains contains} {@code
064   * value}, or {@code null} if this range set does not contain {@code value}.
065   */
066  Range<C> rangeContaining(C value);
067
068  /**
069   * Returns {@code true} if there exists a non-empty range enclosed by both a member range in this
070   * range set and the specified range. This is equivalent to calling {@code
071   * subRangeSet(otherRange)} and testing whether the resulting range set is non-empty.
072   *
073   * @since 20.0
074   */
075  boolean intersects(Range<C> otherRange);
076
077  /**
078   * Returns {@code true} if there exists a member range in this range set which {@linkplain
079   * Range#encloses encloses} the specified range.
080   */
081  boolean encloses(Range<C> otherRange);
082
083  /**
084   * Returns {@code true} if for each member range in {@code other} there exists a member range in
085   * this range set which {@linkplain Range#encloses encloses} it. It follows that {@code
086   * this.contains(value)} whenever {@code other.contains(value)}. Returns {@code true} if {@code
087   * other} is empty.
088   *
089   * <p>This is equivalent to checking if this range set {@link #encloses} each of the ranges in
090   * {@code other}.
091   */
092  boolean enclosesAll(RangeSet<C> other);
093
094  /**
095   * Returns {@code true} if for each range in {@code other} there exists a member range in this
096   * range set which {@linkplain Range#encloses encloses} it. Returns {@code true} if {@code other}
097   * is empty.
098   *
099   * <p>This is equivalent to checking if this range set {@link #encloses} each range in {@code
100   * other}.
101   *
102   * @since 21.0
103   */
104  boolean enclosesAll(Iterable<Range<C>> other);
105
106  /** Returns {@code true} if this range set contains no ranges. */
107  boolean isEmpty();
108
109  /**
110   * Returns the minimal range which {@linkplain Range#encloses(Range) encloses} all ranges in this
111   * range set.
112   *
113   * @throws NoSuchElementException if this range set is {@linkplain #isEmpty() empty}
114   */
115  Range<C> span();
116
117  // Views
118
119  /**
120   * Returns a view of the {@linkplain Range#isConnected disconnected} ranges that make up this
121   * range set. The returned set may be empty. The iterators returned by its {@link
122   * Iterable#iterator} method return the ranges in increasing order of lower bound (equivalently,
123   * of upper bound).
124   */
125  Set<Range<C>> asRanges();
126
127  /**
128   * Returns a descending view of the {@linkplain Range#isConnected disconnected} ranges that make
129   * up this range set. The returned set may be empty. The iterators returned by its {@link
130   * Iterable#iterator} method return the ranges in decreasing order of lower bound (equivalently,
131   * of upper bound).
132   *
133   * @since 19.0
134   */
135  Set<Range<C>> asDescendingSetOfRanges();
136
137  /**
138   * Returns a view of the complement of this {@code RangeSet}.
139   *
140   * <p>The returned view supports the {@link #add} operation if this {@code RangeSet} supports
141   * {@link #remove}, and vice versa.
142   */
143  RangeSet<C> complement();
144
145  /**
146   * Returns a view of the intersection of this {@code RangeSet} with the specified range.
147   *
148   * <p>The returned view supports all optional operations supported by this {@code RangeSet}, with
149   * the caveat that an {@link IllegalArgumentException} is thrown on an attempt to {@linkplain
150   * #add(Range) add} any range not {@linkplain Range#encloses(Range) enclosed} by {@code view}.
151   */
152  RangeSet<C> subRangeSet(Range<C> view);
153
154  // Modification
155
156  /**
157   * Adds the specified range to this {@code RangeSet} (optional operation). That is, for equal
158   * range sets a and b, the result of {@code a.add(range)} is that {@code a} will be the minimal
159   * range set for which both {@code a.enclosesAll(b)} and {@code a.encloses(range)}.
160   *
161   * <p>Note that {@code range} will be {@linkplain Range#span(Range) coalesced} with any ranges in
162   * the range set that are {@linkplain Range#isConnected(Range) connected} with it. Moreover, if
163   * {@code range} is empty, this is a no-op.
164   *
165   * @throws UnsupportedOperationException if this range set does not support the {@code add}
166   *     operation
167   */
168  void add(Range<C> range);
169
170  /**
171   * Removes the specified range from this {@code RangeSet} (optional operation). After this
172   * operation, if {@code range.contains(c)}, {@code this.contains(c)} will return {@code false}.
173   *
174   * <p>If {@code range} is empty, this is a no-op.
175   *
176   * @throws UnsupportedOperationException if this range set does not support the {@code remove}
177   *     operation
178   */
179  void remove(Range<C> range);
180
181  /**
182   * Removes all ranges from this {@code RangeSet} (optional operation). After this operation,
183   * {@code this.contains(c)} will return false for all {@code c}.
184   *
185   * <p>This is equivalent to {@code remove(Range.all())}.
186   *
187   * @throws UnsupportedOperationException if this range set does not support the {@code clear}
188   *     operation
189   */
190  void clear();
191
192  /**
193   * Adds all of the ranges from the specified range set to this range set (optional operation).
194   * After this operation, this range set is the minimal range set that {@linkplain
195   * #enclosesAll(RangeSet) encloses} both the original range set and {@code other}.
196   *
197   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
198   *
199   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
200   *     operation
201   */
202  void addAll(RangeSet<C> other);
203
204  /**
205   * Adds all of the specified ranges to this range set (optional operation). After this operation,
206   * this range set is the minimal range set that {@linkplain #enclosesAll(RangeSet) encloses} both
207   * the original range set and each range in {@code other}.
208   *
209   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
210   *
211   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
212   *     operation
213   * @since 21.0
214   */
215  void addAll(Iterable<Range<C>> ranges);
216
217  /**
218   * Removes all of the ranges from the specified range set from this range set (optional
219   * operation). After this operation, if {@code other.contains(c)}, {@code this.contains(c)} will
220   * return {@code false}.
221   *
222   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
223   * turn.
224   *
225   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
226   *     operation
227   */
228  void removeAll(RangeSet<C> other);
229
230  /**
231   * Removes all of the specified ranges from this range set (optional operation).
232   *
233   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
234   * turn.
235   *
236   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
237   *     operation
238   * @since 21.0
239   */
240  void removeAll(Iterable<Range<C>> ranges);
241
242  // Object methods
243
244  /**
245   * Returns {@code true} if {@code obj} is another {@code RangeSet} that contains the same ranges
246   * according to {@link Range#equals(Object)}.
247   */
248  @Override
249  boolean equals(@NullableDecl Object obj);
250
251  /** Returns {@code asRanges().hashCode()}. */
252  @Override
253  int hashCode();
254
255  /**
256   * Returns a readable string representation of this range set. For example, if this {@code
257   * RangeSet} consisted of {@code Range.closed(1, 3)} and {@code Range.greaterThan(4)}, this might
258   * return {@code " [1..3](4..+∞)}"}.
259   */
260  @Override
261  String toString();
262}