Following synchronous function are used to transform the items emitted by Flux and Mono

Class Flux

public final <V> Flux<V> map(Function<? super T,? extends V> mapper)

Class Mono

public final <R> Mono<R> map(Function<? super T,? extends R> mapper)

Example

public class MapOperationExample {
    public static void main(String[] args) {
        System.out.println("-- Mapping Flux elements --");
        Flux.just(2, 4, 6, 8)
            .map(n -> n / 2)
            .subscribe(System.out::println);

        System.out.println("-- Mapping Mono element --");
        Mono.just("supercalifragilisticexpialidocious")
            .map(s -> s.length())
            .subscribe(System.out::println);
    }
}

-- Mapping Flux elements --
1
2
3
4
-- Mapping Mono element --
34

Example Project

Dependencies and Technologies Used:

• reactor-core 3.3.2.RELEASE: Non-Blocking Reactive Foundation for the JVM.
• JDK 8
• Maven 3.5.4