public
interface
Function
java.util.function.Function<T, R> |
Known Indirect Subclasses |
Represents a function that accepts one argument and produces a result.
This is a functional interface
whose functional method is apply(Object)
.
Public methods | |
---|---|
default
<V>
Function<T, V>
|
andThen(Function<? super R, ? extends V> after)
Returns a composed function that first applies this function to
its input, and then applies the |
abstract
R
|
apply(T t)
Applies this function to the given argument. |
default
<V>
Function<V, R>
|
compose(Function<? super V, ? extends T> before)
Returns a composed function that first applies the |
static
<T>
Function<T, T>
|
identity()
Returns a function that always returns its input argument. |
Function<T, V> andThen (Function<? super R, ? extends V> after)
Returns a composed function that first applies this function to
its input, and then applies the after
function to the result.
If evaluation of either function throws an exception, it is relayed to
the caller of the composed function.
Parameters | |
---|---|
after |
Function :
the function to apply after this function is applied |
Returns | |
---|---|
Function<T, V> |
a composed function that first applies this function and then
applies the after function |
Throws | |
---|---|
NullPointerException |
if after is null |
See also:
R apply (T t)
Applies this function to the given argument.
Parameters | |
---|---|
t |
T :
the function argument |
Returns | |
---|---|
R |
the function result |
Function<V, R> compose (Function<? super V, ? extends T> before)
Returns a composed function that first applies the before
function to its input, and then applies this function to the result.
If evaluation of either function throws an exception, it is relayed to
the caller of the composed function.
Parameters | |
---|---|
before |
Function :
the function to apply before this function is applied |
Returns | |
---|---|
Function<V, R> |
a composed function that first applies the before
function and then applies this function |
Throws | |
---|---|
NullPointerException |
if before is null |
See also:
Function<T, T> identity ()
Returns a function that always returns its input argument.
Returns | |
---|---|
Function<T, T> |
a function that always returns its input argument |