Class Long2IntFunctions


  • public final class Long2IntFunctions
    extends Object
    A class providing static methods and objects that do useful things with type-specific functions.
    See Also:
    Function, Collections
    • Field Detail

      • EMPTY_FUNCTION

        public static final Long2IntFunctions.EmptyFunction EMPTY_FUNCTION
        An empty type-specific function (immutable). It is serializable and cloneable.
    • Method Detail

      • singleton

        public static Long2IntFunction singleton​(long key,
                                                 int value)
        Returns a type-specific immutable function containing only the specified pair. The returned function is serializable and cloneable.

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

        Parameters:
        key - the only key of the returned function.
        value - the only value of the returned function.
        Returns:
        a type-specific immutable function containing just the pair <key,value>.
      • singleton

        public static Long2IntFunction singleton​(Long key,
                                                 Integer value)
        Returns a type-specific immutable function containing only the specified pair. The returned function is serializable and cloneable.

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

        Parameters:
        key - the only key of the returned function.
        value - the only value of the returned function.
        Returns:
        a type-specific immutable function containing just the pair <key,value>.
      • synchronize

        public static Long2IntFunction synchronize​(Long2IntFunction f,
                                                   Object sync)
        Returns a synchronized type-specific function backed by the given type-specific function, using an assigned object to synchronize.
        Parameters:
        f - the function to be wrapped in a synchronized function.
        sync - an object that will be used to synchronize the access to the function.
        Returns:
        a synchronized view of the specified function.
        See Also:
        Collections.synchronizedMap(java.util.Map)
      • primitive

        public static Long2IntFunction primitive​(Function<? super Long,​? extends Integer> f)
        Returns a (partial) type-specific function based on the given total generic function.

        The returned function contains all keys which are not mapped to null. If the function already is a primitive function, it is returned without changes.

        Warning: If the given function is a “widened” primitive function (e.g. an Int2IntFunction given to Short2ShortFunctions), it still is wrapped into a proxy, decreasing performance.

        Parameters:
        f - the function to be converted to a type-specific function.
        Returns:
        a primitive view of the specified function.
        Throws:
        NullPointerException - if f is null.
        Since:
        8.1.0
        See Also:
        Long2IntFunctions.PrimitiveFunction