【微服务】RxJava与SpringMVC

RxJava

a library for composing asynchronous and event-based programs by using observable sequences.

是一个使用可观察数据流进行异步编程的编程接口，ReactiveX结合了观察者模式、迭代器模式和函数式编程的精华。与异步数据流交互的编程范式

---

Example

@RequestMapping(method = RequestMethod.GET, value = "/single")
public Single<String> single() {
    return Single.just("single value");
}

---

@RequestMapping(method = RequestMethod.GET, value = "/singleWithResponse")
public ResponseEntity<Single<String>> singleWithResponse() {
    return new ResponseEntity<>(Single.just("single value"), HttpStatus.NOT_FOUND);
}

---

@RequestMapping(method = RequestMethod.GET, value = "/throw")
public Single<Object> error() {
    return Single.error(new RuntimeException("Unexpected"));
}

---

@RequestMapping(method = RequestMethod.GET, value = "/single")
public Single single() {
    return Observable.just("single value").toSingle();
}

@RequestMapping(method = RequestMethod.GET, value = "/multiple")
public Single> multiple() {
    return Observable.just("multiple", "values").toList().toSingle();
}

@RequestMapping(method = RequestMethod.GET, value = "/responseWithObservable")
public ResponseEntity> responseWithObservable() {

    Observable observable = Observable.just("single value");
    HttpHeaders headers = new HttpHeaders();
    headers.setContentType(APPLICATION_JSON_UTF8);
    return new ResponseEntity<>(observable.toSingle(), headers, HttpStatus.CREATED);
}

@RequestMapping(method = RequestMethod.GET, value = "/timeout")
public Observable timeout() {
    return Observable.timer(1, TimeUnit.MINUTES).map(new Func1() {
        @Override
        public String call(Long aLong) {
            return "single value";
        }
    });
}

---

@RequestMapping(method = RequestMethod.GET, value = "/sse")
public SseEmitter single() {
    return RxResponse.sse(Observable.just("single value"));
}

@RequestMapping(method = RequestMethod.GET, value = "/messages")
public SseEmitter messages() {
    return RxResponse.sse(Observable.just("message 1", "message 2", "message 3"));
}

@RequestMapping(method = RequestMethod.GET, value = "/events")
public SseEmitter event() {
    return RxResponse.sse(APPLICATION_JSON_UTF8, Observable.just(
            new EventDto("Spring io", getDate(2016, 5, 19)),
            new EventDto("SpringOnePlatform", getDate(2016, 8, 1))
    ));
}