Hands-On Reactive Programming in Spring 5

Implementing business logic

The TemperatureSensor class previously sent events to a Spring ApplicationEventPublisher, but now it should return a reactive stream with Temperature events. The Reactive implementation of TemperatureSensor may look like the following:

@Component                                                          // (1)public class TemperatureSensor {   private final Random rnd = new Random();                         // (2)   private final Observable<Temperature> dataStream =               // (3)      Observable         .range(0, Integer.MAX_VALUE)                               // (4)         .concatMap(tick -> Observable                              // (5)            .just(tick)                                             // (6)            .delay(rnd.nextInt(5000), MILLISECONDS)                 // (7)            .map(tickValue -> this.probe()))                        // (8)         .publish()                                                 // (9)         .refCount();                                               // (10)   private Temperature probe() {      return new Temperature(16 + rnd.nextGaussian() * 10);         // (11)   } public ...