1 /* 2 * Copyright (C) 2012 The Guava Authors 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 17 package com.google.common.collect; 18 19 import com.google.common.annotations.Beta; 20 21 import java.util.Map; 22 23 import javax.annotation.Nullable; 24 25 /** 26 * A mapping from disjoint nonempty ranges to non-null values. Queries look up the value 27 * associated with the range (if any) that contains a specified key. 28 * 29 * <p>In contrast to {@link RangeSet}, no "coalescing" is done of {@linkplain 30 * Range#isConnected(Range) connected} ranges, even if they are mapped to the same value. 31 * 32 * @author Louis Wasserman 33 * @since 14.0 34 */ 35 @Beta 36 public interface RangeMap<K extends Comparable, V> { 37 /** 38 * Returns the value associated with the specified key, or {@code null} if there is no 39 * such value. 40 * 41 * <p>Specifically, if any range in this range map contains the specified key, the value 42 * associated with that range is returned. 43 */ 44 @Nullable 45 V get(K key); 46 47 /** 48 * Returns the range containing this key and its associated value, if such a range is present 49 * in the range map, or {@code null} otherwise. 50 */ 51 @Nullable 52 Map.Entry<Range<K>, V> getEntry(K key); 53 54 /** 55 * Returns the minimal range {@linkplain Range#encloses(Range) enclosing} the ranges 56 * in this {@code RangeMap}. 57 * 58 * @throws NoSuchElementException if this range map is empty 59 */ 60 Range<K> span(); 61 62 /** 63 * Maps a range to a specified value (optional operation). 64 * 65 * <p>Specifically, after a call to {@code put(range, value)}, if 66 * {@link Range#contains(Comparable) range.contains(k)}, then {@link #get(Comparable) get(k)} 67 * will return {@code value}. 68 * 69 * <p>If {@code range} {@linkplain Range#isEmpty() is empty}, then this is a no-op. 70 */ 71 void put(Range<K> range, V value); 72 73 /** 74 * Puts all the associations from {@code rangeMap} into this range map (optional operation). 75 */ 76 void putAll(RangeMap<K, V> rangeMap); 77 78 /** 79 * Removes all associations from this range map (optional operation). 80 */ 81 void clear(); 82 83 /** 84 * Removes all associations from this range map in the specified range (optional operation). 85 * 86 * <p>If {@code !range.contains(k)}, {@link #get(Comparable) get(k)} will return the same result 87 * before and after a call to {@code remove(range)}. If {@code range.contains(k)}, then 88 * after a call to {@code remove(range)}, {@code get(k)} will return {@code null}. 89 */ 90 void remove(Range<K> range); 91 92 /** 93 * Returns a view of this range map as an unmodifiable {@code Map<Range<K>, V>}. 94 * Modifications to this range map are guaranteed to read through to the returned {@code Map}. 95 * 96 * <p>It is guaranteed that no empty ranges will be in the returned {@code Map}. 97 */ 98 Map<Range<K>, V> asMapOfRanges(); 99 100 /** 101 * Returns a view of the part of this range map that intersects with {@code range}. 102 * 103 * <p>For example, if {@code rangeMap} had the entries 104 * {@code [1, 5] => "foo", (6, 8) => "bar", (10, \u2025) => "baz"} 105 * then {@code rangeMap.subRangeMap(Range.open(3, 12))} would return a range map 106 * with the entries {@code (3, 5) => "foo", (6, 8) => "bar", (10, 12) => "baz"}. 107 * 108 * <p>The returned range map supports all optional operations that this range map supports, 109 * except for {@code asMapOfRanges().iterator().remove()}. 110 * 111 * <p>The returned range map will throw an {@link IllegalArgumentException} on an attempt to 112 * insert a range not {@linkplain Range#encloses(Range) enclosed} by {@code range}. 113 */ 114 RangeMap<K, V> subRangeMap(Range<K> range); 115 116 /** 117 * Returns {@code true} if {@code obj} is another {@code RangeMap} that has an equivalent 118 * {@link #asMapOfRanges()}. 119 */ 120 @Override 121 boolean equals(@Nullable Object o); 122 123 /** 124 * Returns {@code asMapOfRanges().hashCode()}. 125 */ 126 @Override 127 int hashCode(); 128 129 /** 130 * Returns a readable string representation of this range map. 131 */ 132 @Override 133 String toString(); 134 } 135
