@FunctionalInterface public interface Double2IntFunction extends Function<Double,Integer>, DoubleToIntFunction
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.
Function| Modifier and Type | Method and Description |
|---|---|
default int |
applyAsInt(double operand) |
default boolean |
containsKey(double 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(double 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(double key,
int value)
Adds a pair to the map (optional operation).
|
default Integer |
put(Double key,
Integer value)
Deprecated.
Please use the corresponding type-specific method instead.
|
default int |
remove(double key)
Removes the mapping with the given key (optional operation).
|
default Integer |
remove(Object key)
Deprecated.
Please use the corresponding type-specific method instead.
|
default int applyAsInt(double operand)
applyAsInt in interface DoubleToIntFunctiondefault int put(double key,
int value)
key - the key.value - the value.Function.put(Object,Object)int get(double key)
key - the key.Function.get(Object)default int remove(double key)
key - the key.Function.remove(Object)@Deprecated default Integer put(Double key, Integer value)
key - the key.value - the value.null if no value was present for the given key.Map.put(Object,Object)@Deprecated default Integer get(Object key)
key - the key.null if no value was present for the given key.Map.get(Object)@Deprecated default Integer remove(Object key)
key - the key.null if no value was present for the given key.Map.remove(Object)default boolean containsKey(double 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.
key - the key.key.Function.containsKey(Object)@Deprecated default boolean containsKey(Object 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.
key - the key.key.Map.containsKey(Object)default void defaultReturnValue(int rv)
get(), put() and remove() to
denote that the map does not contain the specified key. It must be
0/false/null by default.rv - the new default return value.defaultReturnValue()default int defaultReturnValue()
This default implementation just return the default null value
of the type (null for objects, 0 for scalars, false for Booleans).
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