使用RestTemplate：

@RestController
public class SampleController {
   @Autowired
   RestTemplate restTemplate;
   @RequestMapping(value = "/sample/endpoint", method = RequestMethod.POST)
   public String createProducts(@RequestBody SampleClass sampleClass) {
      HttpHeaders headers = new HttpHeaders();
      headers.setAccept(Arrays.asList(MediaType.APPLICATION_JSON));
      HttpEntity<SampleClass> entity = new HttpEntity<SampleClass>(sampleClass,headers);
      return restTemplate.exchange(
         "https://example.com/endpoint", HttpMethod.POST, entity, String.class).getBody();
   }
}

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