使用AsynRestTemplate开发服务消费者
概念阐述
AsyncRestTemplate 开发方式允许用户异步的进行服务调用。具体的业务流程和 RestTemplate 类似,只是这里以异步的形式进行服务的调用。
示例代码
AsyncRestTemplate 实例通过 new CseAsyncRestTemplate()来创建和获取,再使用该实例通过自定义的 URL 进行服务调用。
- Spring MVC 客户端代码示例
@Component
public class SpringmvcConsumerMain {
private static final Logger LOG = LoggerFactory.getLogger(SpringmvcConsumerMain.class);
public static void main(String[] args) throws Exception {
init();
Person person = new Person();
person.setName("ServiceComb/Java Chassis");
//AsyncRestTemplate Consumer
CseAsyncRestTemplate cseAsyncRestTemplate = new CseAsyncRestTemplate();
ListenableFuture<ResponseEntity<String>> responseEntityListenableFuture = cseAsyncRestTemplate
.postForEntity("cse://springmvc/springmvchello/sayhi?name=Java Chassis", null, String.class);
ResponseEntity<String> responseEntity = responseEntityListenableFuture.get();
System.out.println("AsyncRestTemplate Consumer sayHi services: " + responseEntity.getBody());
HttpEntity<Person> entity = new HttpEntity<>(person);
ListenableFuture<ResponseEntity<String>> listenableFuture = cseAsyncRestTemplate
.exchange("cse://springmvc/springmvchello/sayhello", HttpMethod.POST, entity, String.class);
// ResponseEntity<String> responseEntity1 = listenableFuture.get();
// System.out.println("AsyncRestTemplate Consumer sayHello services: " + responseEntity1.getBody());
//设置回调函数
listenableFuture.addCallback(
new ListenableFutureCallback<ResponseEntity<String>>() {
@Override
public void onFailure(Throwable ex) {
LOG.error("AsyncResTemplate Consumer catched exception when sayHello, ", ex);
}
@Override
public void onSuccess(ResponseEntity<String> result) {
System.out.println("AsyncRestTemplate Consumer sayHello services: " + result.getBody());
}
});
}
public static void init() throws Exception {
Log4jUtils.init();
BeanUtils.init();
}
}
说明 :
- URL 的格式和 RestTemplate 一样,具体可以参考 restTemplate
- 这里用自定义的 ListenableFuture 类来作为占位符,获取远程调用结束后可能获取的结果。同时也可以自定义回调函数,对可能返回的结果进行分批处理。