Package com.google.common.collect

Interface RangeMap<K extends Comparable,​V>

  • All Known Implementing Classes:
    ImmutableRangeMap, TreeRangeMap
    @Beta
@DoNotMock("Use ImmutableRangeMap or TreeRangeMap")
@GwtIncompatible
public interface RangeMap<K extends Comparable,​V>
    A mapping from disjoint nonempty ranges to non-null values. Queries look up the value associated with the range (if any) that contains a specified key.

    In contrast to RangeSet, no "coalescing" is done of connected ranges, even if they are mapped to the same value.

    Since:
    14.0
    Author:
    Louis Wasserman

    • Method Summary

      All Methods Instance Methods Abstract Methods 
      Modifier and Type Method Description
      Map<Range<K>,​V> asDescendingMapOfRanges()
      Returns a view of this range map as an unmodifiable Map<Range<K>, V>.
      Map<Range<K>,​V> asMapOfRanges()
      Returns a view of this range map as an unmodifiable Map<Range<K>, V>.
      void clear()
      Removes all associations from this range map (optional operation).
      boolean equals​(Object o)
      Returns true if obj is another RangeMap that has an equivalent asMapOfRanges().
      V get​(K key)
      Returns the value associated with the specified key, or null if there is no such value.
      Map.Entry<Range<K>,​V> getEntry​(K key)
      Returns the range containing this key and its associated value, if such a range is present in the range map, or null otherwise.
      int hashCode()
      Returns asMapOfRanges().hashCode().
      void merge​(Range<K> range, V value, BiFunction<? super V,​? super @Nullable V,​? extends @Nullable V> remappingFunction)
      Merges a value into a part of the map by applying a remapping function.
      void put​(Range<K> range, V value)
      Maps a range to a specified value (optional operation).
      void putAll​(RangeMap<K,​V> rangeMap)
      Puts all the associations from rangeMap into this range map (optional operation).
      void putCoalescing​(Range<K> range, V value)
      Maps a range to a specified value, coalescing this range with any existing ranges with the same value that are connected to this range.
      void remove​(Range<K> range)
      Removes all associations from this range map in the specified range (optional operation).
      Range<K> span()
      Returns the minimal range enclosing the ranges in this RangeMap.
      RangeMap<K,​V> subRangeMap​(Range<K> range)
      Returns a view of the part of this range map that intersects with range.
      String toString()
      Returns a readable string representation of this range map.

    • Method Detail

      • get

        @CheckForNull
V get​(K key)
        Returns the value associated with the specified key, or null if there is no such value.

        Specifically, if any range in this range map contains the specified key, the value associated with that range is returned.

      • getEntry

        @CheckForNull
Map.Entry<Range<K>,​V> getEntry​(K key)
        Returns the range containing this key and its associated value, if such a range is present in the range map, or null otherwise.

      • put

        void put​(Range<K> range,
         V value)
        Maps a range to a specified value (optional operation).

        Specifically, after a call to put(range, value), if range.contains(k), then get(k) will return value.

        If range is empty, then this is a no-op.

      • putCoalescing

        void putCoalescing​(Range<K> range,
                   V value)
        Maps a range to a specified value, coalescing this range with any existing ranges with the same value that are connected to this range.

        The behavior of get(k) after calling this method is identical to the behavior described in put(range, value), however the ranges returned from asMapOfRanges() will be different if there were existing entries which connect to the given range and value.

        Even if the input range is empty, if it is connected on both sides by ranges mapped to the same value those two ranges will be coalesced.

        Note: coalescing requires calling .equals() on any connected values, which may be expensive depending on the value type. Using this method on range maps with large values such as Collection types is discouraged.

        Since:
        22.0

      • putAll

        void putAll​(RangeMap<K,​V> rangeMap)
        Puts all the associations from rangeMap into this range map (optional operation).

      • clear

        void clear()
        Removes all associations from this range map (optional operation).

      • remove

        void remove​(Range<K> range)
        Removes all associations from this range map in the specified range (optional operation).

        If !range.contains(k), get(k) will return the same result before and after a call to remove(range). If range.contains(k), then after a call to remove(range), get(k) will return null.

      • merge

        void merge​(Range<K> range,
           @CheckForNull
           V value,
           BiFunction<? super V,​? super @Nullable V,​? extends @Nullable V> remappingFunction)
        Merges a value into a part of the map by applying a remapping function.

        If any parts of the range are already present in this map, those parts are mapped to new values by applying the remapping function. The remapping function accepts the map's existing value for that part of the range and the given value. It returns the value to be associated with that part of the map, or it returns null to clear that part of the map.

        Any parts of the range not already present in this map are mapped to the specified value, unless the value is null.

        Any existing entry spanning either range boundary may be split at the boundary, even if the merge does not affect its value. For example, if rangeMap had one entry [1, 5] => 3 then rangeMap.merge(Range.closed(0,2), 3, Math::max) could yield a map with the entries [0, 1) => 3, [1, 2] => 3, (2, 5] => 3.

        Since:
        28.1

      • asMapOfRanges

        Map<Range<K>,​V> asMapOfRanges()
        Returns a view of this range map as an unmodifiable Map<Range<K>, V>. Modifications to this range map are guaranteed to read through to the returned Map.

        The returned Map iterates over entries in ascending order of the bounds of the Range entries.

        It is guaranteed that no empty ranges will be in the returned Map.

      • asDescendingMapOfRanges

        Map<Range<K>,​V> asDescendingMapOfRanges()
        Returns a view of this range map as an unmodifiable Map<Range<K>, V>. Modifications to this range map are guaranteed to read through to the returned Map.

        The returned Map iterates over entries in descending order of the bounds of the Range entries.

        It is guaranteed that no empty ranges will be in the returned Map.

        Since:
        19.0

      • subRangeMap

        RangeMap<K,​V> subRangeMap​(Range<K> range)
        Returns a view of the part of this range map that intersects with range.

        For example, if rangeMap had the entries [1, 5] => "foo", (6, 8) => "bar", (10, ∞) => "baz" then rangeMap.subRangeMap(Range.open(3, 12)) would return a range map with the entries (3, 5] => "foo", (6, 8) => "bar", (10, 12) => "baz".

        The returned range map supports all optional operations that this range map supports, except for asMapOfRanges().iterator().remove().

        The returned range map will throw an IllegalArgumentException on an attempt to insert a range not enclosed by range.

      • toString

        String toString()
        Returns a readable string representation of this range map.
        Overrides:
        toString in class Object
        Returns:
        a string representation of the object.