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 javax.annotation.CheckForNull;
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
054@ElementTypesAreNonnullByDefault
055public interface RangeSet<C extends Comparable> {
056  // TODO(lowasser): consider adding default implementations of some of these methods
057
058  // Query methods
059
060  /** Determines whether any of this range set's member ranges contains {@code value}. */
061  boolean contains(C value);
062
063  /**
064   * Returns the unique range from this range set that {@linkplain Range#contains contains} {@code
065   * value}, or {@code null} if this range set does not contain {@code value}.
066   */
067  @CheckForNull
068  Range<C> rangeContaining(C value);
069
070  /**
071   * Returns {@code true} if there exists a non-empty range enclosed by both a member range in this
072   * range set and the specified range. This is equivalent to calling {@code
073   * subRangeSet(otherRange)} and testing whether the resulting range set is non-empty.
074   *
075   * @since 20.0
076   */
077  boolean intersects(Range<C> otherRange);
078
079  /**
080   * Returns {@code true} if there exists a member range in this range set which {@linkplain
081   * Range#encloses encloses} the specified range.
082   */
083  boolean encloses(Range<C> otherRange);
084
085  /**
086   * Returns {@code true} if for each member range in {@code other} there exists a member range in
087   * this range set which {@linkplain Range#encloses encloses} it. It follows that {@code
088   * this.contains(value)} whenever {@code other.contains(value)}. Returns {@code true} if {@code
089   * other} is empty.
090   *
091   * <p>This is equivalent to checking if this range set {@link #encloses} each of the ranges in
092   * {@code other}.
093   */
094  boolean enclosesAll(RangeSet<C> other);
095
096  /**
097   * Returns {@code true} if for each range in {@code other} there exists a member range in this
098   * range set which {@linkplain Range#encloses encloses} it. Returns {@code true} if {@code other}
099   * is empty.
100   *
101   * <p>This is equivalent to checking if this range set {@link #encloses} each range in {@code
102   * other}.
103   *
104   * @since 21.0
105   */
106  default boolean enclosesAll(Iterable<Range<C>> other) {
107    for (Range<C> range : other) {
108      if (!encloses(range)) {
109        return false;
110      }
111    }
112    return true;
113  }
114
115  /** Returns {@code true} if this range set contains no ranges. */
116  boolean isEmpty();
117
118  /**
119   * Returns the minimal range which {@linkplain Range#encloses(Range) encloses} all ranges in this
120   * range set.
121   *
122   * @throws NoSuchElementException if this range set is {@linkplain #isEmpty() empty}
123   */
124  Range<C> span();
125
126  // Views
127
128  /**
129   * Returns a view of the {@linkplain Range#isConnected disconnected} ranges that make up this
130   * range set. The returned set may be empty. The iterators returned by its {@link
131   * Iterable#iterator} method return the ranges in increasing order of lower bound (equivalently,
132   * of upper bound).
133   */
134  Set<Range<C>> asRanges();
135
136  /**
137   * Returns a descending view of the {@linkplain Range#isConnected disconnected} ranges that make
138   * up this range set. The returned set may be empty. The iterators returned by its {@link
139   * Iterable#iterator} method return the ranges in decreasing order of lower bound (equivalently,
140   * of upper bound).
141   *
142   * @since 19.0
143   */
144  Set<Range<C>> asDescendingSetOfRanges();
145
146  /**
147   * Returns a view of the complement of this {@code RangeSet}.
148   *
149   * <p>The returned view supports the {@link #add} operation if this {@code RangeSet} supports
150   * {@link #remove}, and vice versa.
151   */
152  RangeSet<C> complement();
153
154  /**
155   * Returns a view of the intersection of this {@code RangeSet} with the specified range.
156   *
157   * <p>The returned view supports all optional operations supported by this {@code RangeSet}, with
158   * the caveat that an {@link IllegalArgumentException} is thrown on an attempt to {@linkplain
159   * #add(Range) add} any range not {@linkplain Range#encloses(Range) enclosed} by {@code view}.
160   */
161  RangeSet<C> subRangeSet(Range<C> view);
162
163  // Modification
164
165  /**
166   * Adds the specified range to this {@code RangeSet} (optional operation). That is, for equal
167   * range sets a and b, the result of {@code a.add(range)} is that {@code a} will be the minimal
168   * range set for which both {@code a.enclosesAll(b)} and {@code a.encloses(range)}.
169   *
170   * <p>Note that {@code range} will be {@linkplain Range#span(Range) coalesced} with any ranges in
171   * the range set that are {@linkplain Range#isConnected(Range) connected} with it. Moreover, if
172   * {@code range} is empty, this is a no-op.
173   *
174   * @throws UnsupportedOperationException if this range set does not support the {@code add}
175   *     operation
176   */
177  void add(Range<C> range);
178
179  /**
180   * Removes the specified range from this {@code RangeSet} (optional operation). After this
181   * operation, if {@code range.contains(c)}, {@code this.contains(c)} will return {@code false}.
182   *
183   * <p>If {@code range} is empty, this is a no-op.
184   *
185   * @throws UnsupportedOperationException if this range set does not support the {@code remove}
186   *     operation
187   */
188  void remove(Range<C> range);
189
190  /**
191   * Removes all ranges from this {@code RangeSet} (optional operation). After this operation,
192   * {@code this.contains(c)} will return false for all {@code c}.
193   *
194   * <p>This is equivalent to {@code remove(Range.all())}.
195   *
196   * @throws UnsupportedOperationException if this range set does not support the {@code clear}
197   *     operation
198   */
199  void clear();
200
201  /**
202   * Adds all of the ranges from the specified range set to this range set (optional operation).
203   * After this operation, this range set is the minimal range set that {@linkplain
204   * #enclosesAll(RangeSet) encloses} both the original range set and {@code other}.
205   *
206   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
207   *
208   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
209   *     operation
210   */
211  void addAll(RangeSet<C> other);
212
213  /**
214   * Adds all of the specified ranges to this range set (optional operation). After this operation,
215   * this range set is the minimal range set that {@linkplain #enclosesAll(RangeSet) encloses} both
216   * the original range set and each range in {@code other}.
217   *
218   * <p>This is equivalent to calling {@link #add} on each of the ranges in {@code other} in turn.
219   *
220   * @throws UnsupportedOperationException if this range set does not support the {@code addAll}
221   *     operation
222   * @since 21.0
223   */
224  default void addAll(Iterable<Range<C>> ranges) {
225    for (Range<C> range : ranges) {
226      add(range);
227    }
228  }
229
230  /**
231   * Removes all of the ranges from the specified range set from this range set (optional
232   * operation). After this operation, if {@code other.contains(c)}, {@code this.contains(c)} will
233   * return {@code false}.
234   *
235   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
236   * turn.
237   *
238   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
239   *     operation
240   */
241  void removeAll(RangeSet<C> other);
242
243  /**
244   * Removes all of the specified ranges from this range set (optional operation).
245   *
246   * <p>This is equivalent to calling {@link #remove} on each of the ranges in {@code other} in
247   * turn.
248   *
249   * @throws UnsupportedOperationException if this range set does not support the {@code removeAll}
250   *     operation
251   * @since 21.0
252   */
253  default void removeAll(Iterable<Range<C>> ranges) {
254    for (Range<C> range : ranges) {
255      remove(range);
256    }
257  }
258
259  // Object methods
260
261  /**
262   * Returns {@code true} if {@code obj} is another {@code RangeSet} that contains the same ranges
263   * according to {@link Range#equals(Object)}.
264   */
265  @Override
266  boolean equals(@CheckForNull Object obj);
267
268  /** Returns {@code asRanges().hashCode()}. */
269  @Override
270  int hashCode();
271
272  /**
273   * Returns a readable string representation of this range set. For example, if this {@code
274   * RangeSet} consisted of {@code Range.closed(1, 3)} and {@code Range.greaterThan(4)}, this might
275   * return {@code " [1..3](4..+∞)}"}.
276   */
277  @Override
278  String toString();
279}