Added in API level 24
    LongFunction
@FunctionalInterface interface LongFunction<R : Any!>
| java.util.function.LongFunction | 
Represents a function that accepts a long-valued argument and produces a result. This is the long-consuming primitive specialization for Function. 
This is a functional interface whose functional method is apply(long).
Summary
| Public methods | |
|---|---|
| abstract R | 
            
             Applies this function to the given argument.  | 
        
Public methods
apply
Added in API level 24
      abstract fun apply(value: Long): R
Applies this function to the given argument.
| Parameters | |
|---|---|
value | 
            Long: the function argument | 
| Return | |
|---|---|
R | 
            the function result |