Coverage Summary for Class: RegularContiguousSet (com.google.common.collect)

1 /*
2  * Copyright (C) 2011 The Guava Authors
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file except
5  * in compliance with the License. You may obtain a copy of the License at
6  *
7  * http://www.apache.org/licenses/LICENSE-2.0
8  *
9  * Unless required by applicable law or agreed to in writing, software distributed under the License
10  * is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express
11  * or implied. See the License for the specific language governing permissions and limitations under
12  * the License.
13  */
14 
15 package com.google.common.collect;
16 
17 import static com.google.common.base.Preconditions.checkArgument;
18 import static com.google.common.base.Preconditions.checkElementIndex;
19 import static com.google.common.base.Preconditions.checkNotNull;
20 import static com.google.common.collect.BoundType.CLOSED;
21 
22 import com.google.common.annotations.GwtCompatible;
23 import com.google.common.annotations.GwtIncompatible;
24 import java.io.Serializable;
25 import java.util.Collection;
26 import org.checkerframework.checker.nullness.qual.Nullable;
27 
28 /**
29  * An implementation of {@link ContiguousSet} that contains one or more elements.
30  *
31  * @author Gregory Kick
32  */
33 @GwtCompatible(emulated = true)
34 @SuppressWarnings("unchecked") // allow ungenerified Comparable types
35 final class RegularContiguousSet<C extends Comparable> extends ContiguousSet<C> {
36   private final Range<C> range;
37 
38   RegularContiguousSet(Range<C> range, DiscreteDomain<C> domain) {
39     super(domain);
40     this.range = range;
41   }
42 
43   private ContiguousSet<C> intersectionInCurrentDomain(Range<C> other) {
44     return range.isConnected(other)
45         ? ContiguousSet.create(range.intersection(other), domain)
46         : new EmptyContiguousSet<C>(domain);
47   }
48 
49   @Override
50   ContiguousSet<C> headSetImpl(C toElement, boolean inclusive) {
51     return intersectionInCurrentDomain(Range.upTo(toElement, BoundType.forBoolean(inclusive)));
52   }
53 
54   @Override
55   ContiguousSet<C> subSetImpl(
56       C fromElement, boolean fromInclusive, C toElement, boolean toInclusive) {
57     if (fromElement.compareTo(toElement) == 0 && !fromInclusive && !toInclusive) {
58       // Range would reject our attempt to create (x, x).
59       return new EmptyContiguousSet<C>(domain);
60     }
61     return intersectionInCurrentDomain(
62         Range.range(
63             fromElement, BoundType.forBoolean(fromInclusive),
64             toElement, BoundType.forBoolean(toInclusive)));
65   }
66 
67   @Override
68   ContiguousSet<C> tailSetImpl(C fromElement, boolean inclusive) {
69     return intersectionInCurrentDomain(Range.downTo(fromElement, BoundType.forBoolean(inclusive)));
70   }
71 
72   @GwtIncompatible // not used by GWT emulation
73   @Override
74   int indexOf(Object target) {
75     return contains(target) ? (int) domain.distance(first(), (C) target) : -1;
76   }
77 
78   @Override
79   public UnmodifiableIterator<C> iterator() {
80     return new AbstractSequentialIterator<C>(first()) {
81       final C last = last();
82 
83       @Override
84       protected C computeNext(C previous) {
85         return equalsOrThrow(previous, last) ? null : domain.next(previous);
86       }
87     };
88   }
89 
90   @GwtIncompatible // NavigableSet
91   @Override
92   public UnmodifiableIterator<C> descendingIterator() {
93     return new AbstractSequentialIterator<C>(last()) {
94       final C first = first();
95 
96       @Override
97       protected C computeNext(C previous) {
98         return equalsOrThrow(previous, first) ? null : domain.previous(previous);
99       }
100     };
101   }
102 
103   private static boolean equalsOrThrow(Comparable<?> left, @Nullable Comparable<?> right) {
104     return right != null && Range.compareOrThrow(left, right) == 0;
105   }
106 
107   @Override
108   boolean isPartialView() {
109     return false;
110   }
111 
112   @Override
113   public C first() {
114     return range.lowerBound.leastValueAbove(domain);
115   }
116 
117   @Override
118   public C last() {
119     return range.upperBound.greatestValueBelow(domain);
120   }
121 
122   @Override
123   ImmutableList<C> createAsList() {
124     if (domain.supportsFastOffset) {
125       return new ImmutableAsList<C>() {
126         @Override
127         ImmutableSortedSet<C> delegateCollection() {
128           return RegularContiguousSet.this;
129         }
130 
131         @Override
132         public C get(int i) {
133           checkElementIndex(i, size());
134           return domain.offset(first(), i);
135         }
136       };
137     } else {
138       return super.createAsList();
139     }
140   }
141 
142   @Override
143   public int size() {
144     long distance = domain.distance(first(), last());
145     return (distance >= Integer.MAX_VALUE) ? Integer.MAX_VALUE : (int) distance + 1;
146   }
147 
148   @Override
149   public boolean contains(@Nullable Object object) {
150     if (object == null) {
151       return false;
152     }
153     try {
154       return range.contains((C) object);
155     } catch (ClassCastException e) {
156       return false;
157     }
158   }
159 
160   @Override
161   public boolean containsAll(Collection<?> targets) {
162     return Collections2.containsAllImpl(this, targets);
163   }
164 
165   @Override
166   public boolean isEmpty() {
167     return false;
168   }
169 
170   @Override
171   public ContiguousSet<C> intersection(ContiguousSet<C> other) {
172     checkNotNull(other);
173     checkArgument(this.domain.equals(other.domain));
174     if (other.isEmpty()) {
175       return other;
176     } else {
177       C lowerEndpoint = Ordering.natural().max(this.first(), other.first());
178       C upperEndpoint = Ordering.natural().min(this.last(), other.last());
179       return (lowerEndpoint.compareTo(upperEndpoint) <= 0)
180           ? ContiguousSet.create(Range.closed(lowerEndpoint, upperEndpoint), domain)
181           : new EmptyContiguousSet<C>(domain);
182     }
183   }
184 
185   @Override
186   public Range<C> range() {
187     return range(CLOSED, CLOSED);
188   }
189 
190   @Override
191   public Range<C> range(BoundType lowerBoundType, BoundType upperBoundType) {
192     return Range.create(
193         range.lowerBound.withLowerBoundType(lowerBoundType, domain),
194         range.upperBound.withUpperBoundType(upperBoundType, domain));
195   }
196 
197   @Override
198   public boolean equals(@Nullable Object object) {
199     if (object == this) {
200       return true;
201     } else if (object instanceof RegularContiguousSet) {
202       RegularContiguousSet<?> that = (RegularContiguousSet<?>) object;
203       if (this.domain.equals(that.domain)) {
204         return this.first().equals(that.first()) && this.last().equals(that.last());
205       }
206     }
207     return super.equals(object);
208   }
209 
210   // copied to make sure not to use the GWT-emulated version
211   @Override
212   public int hashCode() {
213     return Sets.hashCodeImpl(this);
214   }
215 
216   @GwtIncompatible // serialization
217   private static final class SerializedForm<C extends Comparable> implements Serializable {
218     final Range<C> range;
219     final DiscreteDomain<C> domain;
220 
221     private SerializedForm(Range<C> range, DiscreteDomain<C> domain) {
222       this.range = range;
223       this.domain = domain;
224     }
225 
226     private Object readResolve() {
227       return new RegularContiguousSet<C>(range, domain);
228     }
229   }
230 
231   @GwtIncompatible // serialization
232   @Override
233   Object writeReplace() {
234     return new SerializedForm<C>(range, domain);
235   }
236 
237   private static final long serialVersionUID = 0;
238 }