下边实现了一个持续返回100以内随机数的接口，在接口超时之前会每隔1秒返回一个随机数 

@GetMapping(value = "/getRandomNum", produces = MediaType.TEXT_EVENT_STREAM_VALUE)
public SseEmitter getRandomNum() {SseEmitter emitter = new SseEmitter();ThreadLocalRandom random = ThreadLocalRandom.current();new Thread(() -> {try {while (true) {int price = random.nextInt(100);emitter.send(SseEmitter.event().data(price));Thread.sleep(1000);}} catch (Exception e) {emitter.completeWithError(e);}}).start();return emitter;
}

下边是postman调用效果图