markdown 春中几种发送请求的方式

Posted 2021-05-05

## Feign
[OpenFeign/feign: Feign makes writing java http clients easier](https://github.com/OpenFeign/feign)
```java
public class FeignUtil {

    public static <T> T getClient(Class<T> clazz) throws Exception{
        return getClient(clazz,StaticContextAccessor.getBean(Environment.class).getProperty("haproxy"));
    }

    public static <T> T getClient(Class<T> clazz,String url) throws Exception{
        return Feign.builder()
                .encoder(new JacksonEncoder())
                .decoder(new JacksonDecoder())
                .options(new Request.Options(1000, 3500))
                .retryer(new Retryer.Default(5000, 5000, 3))
                .target(clazz, url);
    }
}

public interface TestClient {
    @RequestLine(value = "POST /getId")
    @Body("id={id}")
    CommonResponse<JSONObject> getId(@Param("id") Integer id);
}

CommonResponse<JSONObject> response = FeignUtil.getClient(TestClient.class).getId(asr_id);
```
## RestTemplate
[A Guide to the RestTemplate | Baeldung](https://www.baeldung.com/rest-template)
```java
@SpringBootApplication
@EnableScheduling
@EnableFeignClients
public class ScheduleTaskServerApplication {
	public static void main(String[] args) {
		SpringApplication.run(ScheduleTaskServerApplication.class, args);
	}
	@Bean
	@LoadBalanced
	RestTemplate restTemplate(){
		return new RestTemplate();
	}
}

MultiValueMap<String, String> requestEntity = new LinkedMultiValueMap<>();
requestEntity.add("postData", postData);
String url = "xxx.xxx.xxx.xxx/test";
String Response =  this.restTemplate.postForObject(url,requestEntity, String.class);
```
## Unirest
[Unirest - Simplified, lightweight HTTP request client libraries in multiple languages](http://unirest.io/)
```java
String url = "xxx.xxx.xxx.xxx";
Unirest.setTimeouts(500,500);//设置超时时间
MultipartBody postRequest = Unirest.post(url).field("time", new Date().getTime());
postRequest.asString();//使用asString方法时才真正发出请求
```