Interface Byte2IntFunction

All Superinterfaces:
Function<Byte,​Integer>, Function<Byte,​Integer>, IntUnaryOperator
All Known Subinterfaces:
Byte2IntMap, Byte2IntSortedMap
All Known Implementing Classes:
AbstractByte2IntFunction, AbstractByte2IntMap, AbstractByte2IntSortedMap, Byte2IntArrayMap, Byte2IntAVLTreeMap, Byte2IntFunctions.EmptyFunction, Byte2IntFunctions.PrimitiveFunction, Byte2IntFunctions.Singleton, Byte2IntFunctions.SynchronizedFunction, Byte2IntFunctions.UnmodifiableFunction, Byte2IntLinkedOpenHashMap, Byte2IntMaps.EmptyMap, Byte2IntMaps.Singleton, Byte2IntMaps.SynchronizedMap, Byte2IntMaps.UnmodifiableMap, Byte2IntOpenCustomHashMap, Byte2IntOpenHashMap, Byte2IntRBTreeMap, Byte2IntSortedMaps.EmptySortedMap, Byte2IntSortedMaps.Singleton, Byte2IntSortedMaps.SynchronizedSortedMap, Byte2IntSortedMaps.UnmodifiableSortedMap
Functional Interface:
This is a functional interface and can therefore be used as the assignment target for a lambda expression or method reference.

@FunctionalInterface
public interface Byte2IntFunction
extends Function<Byte,​Integer>, IntUnaryOperator
A type-specific Function; provides some additional methods that use polymorphism to avoid (un)boxing.

Type-specific versions of get(), put() and remove() cannot rely on null to denote absence of a key. Rather, they return a default return value, which is set to 0/false at creation, but can be changed using the defaultReturnValue() method.

For uniformity reasons, even functions returning objects implement the default return value (of course, in this case the default return value is initialized to null).

The default implementation of optional operations just throw an UnsupportedOperationException, except for the type-specific containsKey(), which return true. Generic versions of accessors delegate to the corresponding type-specific counterparts following the interface rules.

Warning: to fall in line as much as possible with the standard map interface, it is required that standard versions of get(), put() and remove() for maps with primitive-type keys or values return null to denote missing keys rather than wrap the default return value in an object. In case both keys and values are reference types, the default return value must be returned instead, thus violating the standard map interface when the default return value is not null.

See Also:
Function
  • Method Summary

    Modifier and Type Method Description
    default int applyAsInt​(int operand)
    Deprecated.
    Please use primitive types which don't have to be widened as keys.
    default boolean containsKey​(byte key)
    Returns true if this function contains a mapping for the specified key.
    default boolean containsKey​(Object key)
    Deprecated.
    Please use the corresponding type-specific method instead.
    default int defaultReturnValue()
    Gets the default return value.
    default void defaultReturnValue​(int rv)
    Sets the default return value (optional operation).
    int get​(byte key)
    Returns the value to which the given key is mapped.
    default Integer get​(Object key)
    Deprecated.
    Please use the corresponding type-specific method instead.
    default int put​(byte key, int value)
    Adds a pair to the map (optional operation).
    default Integer put​(Byte key, Integer value)
    Deprecated.
    Please use the corresponding type-specific method instead.
    default int remove​(byte key)
    Removes the mapping with the given key (optional operation).
    default Integer remove​(Object key)
    Deprecated.
    Please use the corresponding type-specific method instead.

    Methods inherited from interface it.unimi.dsi.fastutil.Function

    apply, clear, size

    Methods inherited from interface java.util.function.Function

    andThen, compose

    Methods inherited from interface java.util.function.IntUnaryOperator

    andThen, compose
  • Method Details

    • applyAsInt

      @Deprecated default int applyAsInt​(int operand)
      Deprecated.
      Please use primitive types which don't have to be widened as keys.

      In this default implementation, the key gets narrowed down to the actual key type, throwing an exception if the given key can't be represented in the restricted domain. This is done for interoperability with the Java 8 function environment. Its use is discouraged, as unexpected errors can occur. Instead, the corresponding classes should be used (e.g., Int2IntFunction instead of Short2IntFunction).

      Specified by:
      applyAsInt in interface IntUnaryOperator
      Throws:
      IllegalArgumentException - If the given operand is not an element of the key domain.
      Since:
      8.0.0
    • put

      default int put​(byte key, int value)
      Adds a pair to the map (optional operation).
      Parameters:
      key - the key.
      value - the value.
      Returns:
      the old value, or the default return value if no value was present for the given key.
      See Also:
      Function.put(Object,Object)
    • get

      int get​(byte key)
      Returns the value to which the given key is mapped.
      Parameters:
      key - the key.
      Returns:
      the corresponding value, or the default return value if no value was present for the given key.
      See Also:
      Function.get(Object)
    • remove

      default int remove​(byte key)
      Removes the mapping with the given key (optional operation).
      Parameters:
      key - the key.
      Returns:
      the old value, or the default return value if no value was present for the given key.
      See Also:
      Function.remove(Object)
    • put

      @Deprecated default Integer put​(Byte key, Integer value)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Associates the specified value with the specified key in this function (optional operation).
      Specified by:
      put in interface Function<Byte,​Integer>
      Parameters:
      key - the key.
      value - the value.
      Returns:
      the old value, or null if no value was present for the given key.
      See Also:
      Map.put(Object,Object)
    • get

      @Deprecated default Integer get​(Object key)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Returns the value associated by this function to the specified key.
      Specified by:
      get in interface Function<Byte,​Integer>
      Parameters:
      key - the key.
      Returns:
      the corresponding value, or null if no value was present for the given key.
      See Also:
      Map.get(Object)
    • remove

      @Deprecated default Integer remove​(Object key)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Removes this key and the associated value from this function if it is present (optional operation).
      Specified by:
      remove in interface Function<Byte,​Integer>
      Parameters:
      key - the key.
      Returns:
      the old value, or null if no value was present for the given key.
      See Also:
      Map.remove(Object)
    • containsKey

      default boolean containsKey​(byte key)
      Returns true if this function contains a mapping for the specified key.

      Note that for some kind of functions (e.g., hashes) this method will always return true. In particular, this default implementation always returns true.

      Parameters:
      key - the key.
      Returns:
      true if this function associates a value to key.
      See Also:
      Function.containsKey(Object)
    • containsKey

      @Deprecated default boolean containsKey​(Object key)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Returns true if this function contains a mapping for the specified key.

      Note that for some kind of functions (e.g., hashes) this method will always return true. This default implementation, in particular, always return true.

      Specified by:
      containsKey in interface Function<Byte,​Integer>
      Parameters:
      key - the key.
      Returns:
      true if this function associates a value to key.
      See Also:
      Map.containsKey(Object)
    • defaultReturnValue

      default void defaultReturnValue​(int rv)
      Sets the default return value (optional operation). This value must be returned by type-specific versions of get(), put() and remove() to denote that the map does not contain the specified key. It must be 0/false/null by default.
      Parameters:
      rv - the new default return value.
      See Also:
      defaultReturnValue()
    • defaultReturnValue

      default int defaultReturnValue()
      Gets the default return value.

      This default implementation just return the default null value of the type (null for objects, 0 for scalars, false for Booleans).

      Returns:
      the current default return value.