Package it.unimi.dsi.fastutil.objects

Class Object2ObjectMaps

java.lang.Object
it.unimi.dsi.fastutil.objects.Object2ObjectMaps
public final class Object2ObjectMaps
extends java.lang.Object
A class providing static methods and objects that do useful things with type-specific maps.
See Also:
Collections

  • Field Details

    • EMPTY_MAP

      public static final Object2ObjectMaps.EmptyMap EMPTY_MAP
      An empty type-specific map (immutable). It is serializable and cloneable.

  • Method Details

    • fastIterator

      public static <K,​ V> ObjectIterator<Object2ObjectMap.Entry<K,​V>> fastIterator​(Object2ObjectMap<K,​V> map)
      Returns an iterator that will be fast, if possible, on the entry set of the provided map.
      Parameters:
      map - a map from which we will try to extract a (fast) iterator on the entry set.
      Returns:
      an iterator on the entry set of the given map that will be fast, if possible.
      Since:
      8.0.0

    • fastForEach

      public static <K,​ V> void fastForEach​(Object2ObjectMap<K,​V> map, java.util.function.Consumer<? super Object2ObjectMap.Entry<K,​V>> consumer)
      Iterates quickly, if possible, on the entry set of the provided map.
      Parameters:
      map - a map on which we will try to iterate quickly.
      consumer - the consumer that will be passed to Object2ObjectMap.FastEntrySet.fastForEach(Consumer), if possible, or to Iterable.forEach(Consumer).
      Since:
      8.1.0

    • fastIterable

      public static <K,​ V> ObjectIterable<Object2ObjectMap.Entry<K,​V>> fastIterable​(Object2ObjectMap<K,​V> map)
      Returns an iterable yielding an iterator that will be fast, if possible, on the entry set of the provided map.
      Parameters:
      map - a map from which we will try to extract an iterable yielding a (fast) iterator on the entry set.
      Returns:
      an iterable yielding an iterator on the entry set of the given map that will be fast, if possible.
      Since:
      8.0.0

    • emptyMap

      public static <K,​ V> Object2ObjectMap<K,​V> emptyMap()
      Returns an empty map (immutable). It is serializable and cloneable.

      This method provides a typesafe access to EMPTY_MAP.

      Returns:
      an empty map (immutable).

    • singleton

      public static <K,​ V> Object2ObjectMap<K,​V> singleton​(K key, V value)
      Returns a type-specific immutable map containing only the specified pair. The returned map is serializable and cloneable.

      Note that albeit the returned map is immutable, its default return value may be changed.

      Parameters:
      key - the only key of the returned map.
      value - the only value of the returned map.
      Returns:
      a type-specific immutable map containing just the pair &lt;key,value&gt;.

    • synchronize

      public static <K,​ V> Object2ObjectMap<K,​V> synchronize​(Object2ObjectMap<K,​V> m)
      Returns a synchronized type-specific map backed by the given type-specific map.
      Parameters:
      m - the map to be wrapped in a synchronized map.
      Returns:
      a synchronized view of the specified map.
      See Also:
      Collections.synchronizedMap(Map)

    • synchronize

      public static <K,​ V> Object2ObjectMap<K,​V> synchronize​(Object2ObjectMap<K,​V> m, java.lang.Object sync)
      Returns a synchronized type-specific map backed by the given type-specific map, using an assigned object to synchronize.
      Parameters:
      m - the map to be wrapped in a synchronized map.
      sync - an object that will be used to synchronize the access to the map.
      Returns:
      a synchronized view of the specified map.
      See Also:
      Collections.synchronizedMap(Map)

    • unmodifiable

      public static <K,​ V> Object2ObjectMap<K,​V> unmodifiable​(Object2ObjectMap<? extends K,​? extends V> m)
      Returns an unmodifiable type-specific map backed by the given type-specific map.
      Parameters:
      m - the map to be wrapped in an unmodifiable map.
      Returns:
      an unmodifiable view of the specified map.
      See Also:
      Collections.unmodifiableMap(Map)