Writing pure functions in Java. Listing 1 presents the source code to an example application, DaysInMonth, that is written using an an anonymous inner class and a functional interface.This ...

The UnaryOperator function. Like the Function interface, the UnaryOperator is passed a value and returns a value. However, the distinction between the UnaryOperator and the Function is that the ...

In this example, the method in the functional interface has only one argument, but multiple arguments are completely valid, so long as the number of arguments in the lambda expression match the number ...

Method references only work when the method’s signature is the same as the method in the expected functional interface. As an example, the map() function in Java’s Stream API expects a ...