Package it.unimi.dsi.fastutil.objects

Interface Object2FloatFunction<K>

All Superinterfaces:
Function<K,​java.lang.Float>, java.util.function.Function<K,​java.lang.Float>, java.util.function.ToDoubleFunction<K>
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 Object2FloatFunction<K>
extends Function<K,​java.lang.Float>, java.util.function.ToDoubleFunction<K>
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 Details

    • applyAsDouble

      default double applyAsDouble​(K operand)
      Specified by:
      applyAsDouble in interface java.util.function.ToDoubleFunction<K>
      Since:
      8.0.0

    • put

      default float put​(K key, float 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)

    • getFloat

      float getFloat​(java.lang.Object 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)

    • getOrDefault

      default float getOrDefault​(java.lang.Object key, float defaultValue)
      Returns the value associated by this function to the specified key, or give the specified value if not present.
      Parameters:
      key - the key.
      defaultValue - the value to return if not present.
      Returns:
      the corresponding value, or defaultValue if no value was present for the given key.
      Since:
      8.5.0
      See Also:
      Function.getOrDefault(Object, Object)

    • removeFloat

      default float removeFloat​(java.lang.Object 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 java.lang.Float put​(K key, java.lang.Float 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<K,​java.lang.Float>
      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 java.lang.Float get​(java.lang.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<K,​java.lang.Float>
      Parameters:
      key - the key.
      Returns:
      the corresponding value, or null if no value was present for the given key.
      See Also:
      Map.get(Object)

    • getOrDefault

      @Deprecated default java.lang.Float getOrDefault​(java.lang.Object key, java.lang.Float defaultValue)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Returns the value associated by this function to the specified key, or give the specified value if not present.
      Specified by:
      getOrDefault in interface Function<K,​java.lang.Float>
      Parameters:
      key - the key.
      defaultValue - the default value to return if not present.
      Returns:
      the corresponding value, or defaultValue if no value was present for the given key.
      See Also:
      Map.getOrDefault(Object, Object)

    • remove

      @Deprecated default java.lang.Float remove​(java.lang.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<K,​java.lang.Float>
      Parameters:
      key - the key.
      Returns:
      the old value, or null if no value was present for the given key.
      See Also:
      Map.remove(Object)

    • defaultReturnValue

      default void defaultReturnValue​(float 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 float 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.

    • andThen

      @Deprecated default <T> java.util.function.Function<K,​T> andThen​(java.util.function.Function<? super java.lang.Float,​? extends T> after)
      Deprecated.
      Please use the corresponding type-specific method instead.
      Specified by:
      andThen in interface java.util.function.Function<K,​java.lang.Float>

    • andThenByte

      default Object2ByteFunction<K> andThenByte​(it.unimi.dsi.fastutil.floats.Float2ByteFunction after)

    • composeByte

      default it.unimi.dsi.fastutil.bytes.Byte2FloatFunction composeByte​(Byte2ObjectFunction<K> before)

    • andThenShort

      default Object2ShortFunction<K> andThenShort​(it.unimi.dsi.fastutil.floats.Float2ShortFunction after)

    • composeShort

      default it.unimi.dsi.fastutil.shorts.Short2FloatFunction composeShort​(Short2ObjectFunction<K> before)

    • andThenInt

      default Object2IntFunction<K> andThenInt​(Float2IntFunction after)

    • composeInt

      default Int2FloatFunction composeInt​(Int2ObjectFunction<K> before)

    • andThenLong

      default Object2LongFunction<K> andThenLong​(Float2LongFunction after)

    • composeLong

      default Long2FloatFunction composeLong​(Long2ObjectFunction<K> before)

    • andThenChar

      default Object2CharFunction<K> andThenChar​(it.unimi.dsi.fastutil.floats.Float2CharFunction after)

    • composeChar

      default it.unimi.dsi.fastutil.chars.Char2FloatFunction composeChar​(Char2ObjectFunction<K> before)

    • andThenFloat

      default Object2FloatFunction<K> andThenFloat​(it.unimi.dsi.fastutil.floats.Float2FloatFunction after)

    • composeFloat

      default it.unimi.dsi.fastutil.floats.Float2FloatFunction composeFloat​(Float2ObjectFunction<K> before)

    • andThenDouble

      default Object2DoubleFunction<K> andThenDouble​(Float2DoubleFunction after)

    • composeDouble

      default Double2FloatFunction composeDouble​(Double2ObjectFunction<K> before)

    • andThenObject

      default <T> Object2ObjectFunction<K,​T> andThenObject​(Float2ObjectFunction<? extends T> after)

    • composeObject

      default <T> Object2FloatFunction<T> composeObject​(Object2ObjectFunction<? super T,​? extends K> before)

    • andThenReference

      default <T> Object2ReferenceFunction<K,​T> andThenReference​(it.unimi.dsi.fastutil.floats.Float2ReferenceFunction<? extends T> after)

    • composeReference

      default <T> it.unimi.dsi.fastutil.objects.Reference2FloatFunction<T> composeReference​(Reference2ObjectFunction<? super T,​? extends K> before)