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.GwtIncompatible;
018import com.google.errorprone.annotations.DoNotMock;
019import java.util.NoSuchElementException;
020import java.util.Set;
021import org.checkerframework.checker.nullness.qual.Nullable;
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@SuppressWarnings("rawtypes") // https://github.com/google/guava/issues/989
052@DoNotMock("Use ImmutableRangeSet or TreeRangeSet")
053@GwtIncompatible
054public interface RangeSet<C extends Comparable> {
055  // TODO(lowasser): consider adding default implementations of some of these methods
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  @Nullable 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  default boolean enclosesAll(Iterable<Range<C>> other) {
105    for (Range<C> range : other) {
106      if (!encloses(range)) {
107        return false;
108      }
109    }
110    return true;
111  }
112
113  /** Returns {@code true} if this range set contains no ranges. */
114  boolean isEmpty();
115
116  /**
117   * Returns the minimal range which {@linkplain Range#encloses(Range) encloses} all ranges in this
118   * range set.
119   *
120   * @throws NoSuchElementException if this range set is {@linkplain #isEmpty() empty}
121   */
122  Range<C> span();
123
124  // Views
125
126  /**
127   * Returns a view of the {@linkplain Range#isConnected disconnected} ranges that make up this
128   * range set. The returned set may be empty. The iterators returned by its {@link
129   * Iterable#iterator} method return the ranges in increasing order of lower bound (equivalently,
130   * of upper bound).
131   */
132  Set<Range<C>> asRanges();
133
134  /**
135   * Returns a descending view of the {@linkplain Range#isConnected disconnected} ranges that make
136   * up this range set. The returned set may be empty. The iterators returned by its {@link
137   * Iterable#iterator} method return the ranges in decreasing order of lower bound (equivalently,
138   * of upper bound).
139   *
140   * @since 19.0
141   */
142  Set<Range<C>> asDescendingSetOfRanges();
143
144  /**
145   * Returns a view of the complement of this {@code RangeSet}.
146   *
147   * <p>The returned view supports the {@link #add} operation if this {@code RangeSet} supports
148   * {@link #remove}, and vice versa.
149   */
150  RangeSet<C> complement();
151
152  /**
153   * Returns a view of the intersection of this {@code RangeSet} with the specified range.
154   *
155   * <p>The returned view supports all optional operations supported by this {@code RangeSet}, with
156   * the caveat that an {@link IllegalArgumentException} is thrown on an attempt to {@linkplain
157   * #add(Range) add} any range not {@linkplain Range#encloses(Range) enclosed} by {@code view}.
158   */
159  RangeSet<C> subRangeSet(Range<C> view);
160
161  // Modification
162
163  /**
164   * Adds the specified range to this {@code RangeSet} (optional operation). That is, for equal
165   * range sets a and b, the result of {@code a.add(range)} is that {@code a} will be the minimal
166   * range set for which both {@code a.enclosesAll(b)} and {@code a.encloses(range)}.
167   *
168   * <p>Note that {@code range} will be {@linkplain Range#span(Range) coalesced} with any ranges in
169   * the range set that are {@linkplain Range#isConnected(Range) connected} with it. Moreover, if
170   * {@code range} is empty, this is a no-op.
171   *
172   * @throws UnsupportedOperationException if this range set does not support the {@code add}
173   *     operation
174   */
175  void add(Range<C> range);
176
177  /**
178   * Removes the specified range from this {@code RangeSet} (optional operation). After this
179   * operation, if {@code range.contains(c)}, {@code this.contains(c)} will return {@code false}.
180   *
181   * <p>If {@code range} is empty, this is a no-op.
182   *
183   * @throws UnsupportedOperationException if this range set does not support the {@code remove}
184   *     operation
185   */
186  void remove(Range<C> range);
187
188  /**
189   * Removes all ranges from this {@code RangeSet} (optional operation). After this operation,
190   * {@code this.contains(c)} will return false for all {@code c}.
191   *
192   * <p>This is equivalent to {@code remove(Range.all())}.
193   *
194   * @throws UnsupportedOperationException if this range set does not support the {@code clear}
195   *     operation
196   */
197  void clear();
198
199  /**
200   * Adds all of the ranges from the specified range set to this range set (optional operation).
201   * After this operation, this range set is the minimal range set that {@linkplain
202   * #enclosesAll(RangeSet) encloses} both the original range set and {@code other}.
203   *
204   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
205   *
206   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
207   *     operation
208   */
209  void addAll(RangeSet<C> other);
210
211  /**
212   * Adds all of the specified ranges to this range set (optional operation). After this operation,
213   * this range set is the minimal range set that {@linkplain #enclosesAll(RangeSet) encloses} both
214   * the original range set and each range in {@code other}.
215   *
216   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
217   *
218   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
219   *     operation
220   * @since 21.0
221   */
222  default void addAll(Iterable<Range<C>> ranges) {
223    for (Range<C> range : ranges) {
224      add(range);
225    }
226  }
227
228  /**
229   * Removes all of the ranges from the specified range set from this range set (optional
230   * operation). After this operation, if {@code other.contains(c)}, {@code this.contains(c)} will
231   * return {@code false}.
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   */
239  void removeAll(RangeSet<C> other);
240
241  /**
242   * Removes all of the specified ranges from this range set (optional operation).
243   *
244   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
245   * turn.
246   *
247   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
248   *     operation
249   * @since 21.0
250   */
251  default void removeAll(Iterable<Range<C>> ranges) {
252    for (Range<C> range : ranges) {
253      remove(range);
254    }
255  }
256
257  // Object methods
258
259  /**
260   * Returns {@code true} if {@code obj} is another {@code RangeSet} that contains the same ranges
261   * according to {@link Range#equals(Object)}.
262   */
263  @Override
264  boolean equals(@Nullable Object obj);
265
266  /** Returns {@code asRanges().hashCode()}. */
267  @Override
268  int hashCode();
269
270  /**
271   * Returns a readable string representation of this range set. For example, if this {@code
272   * RangeSet} consisted of {@code Range.closed(1, 3)} and {@code Range.greaterThan(4)}, this might
273   * return {@code " [1..3](4..+∞)}"}.
274   */
275  @Override
276  String toString();
277}