Spring Boot消费REST API时运行报错求助

Hey there! Let's work through this REST API issue together. Since you mentioned hitting an error when calling an API that accepts JSON payloads and returns plain/text responses, let's break down common culprits and debugging steps using the files you referenced:

To narrow this down quickly, please share:

• The full error stack trace from your application logs (e.g., HttpClientErrorException, JsonProcessingException, or HTTP status codes like 400/401/500)
• The code snippet from SpotifyIntegrationApplication.java where you're making the API call
• Any specific error messages returned by the API itself (if visible)

Since the API expects a JSON payload, mismatches between your NewOrder class and the API's required structure are a common cause:

• Double-check that all field names match exactly (watch for camelCase vs snake_case differences — use @JsonProperty("api_field_name") if needed)
• Ensure data types align (e.g., the API expects an integer but your class uses a String)
• Test serialization manually to confirm the output matches the API's schema:

  ObjectMapper mapper = new ObjectMapper();
  System.out.println(mapper.writeValueAsString(new NewOrder())); // Print the serialized JSON
  

Your client setup might be missing critical headers or message converters:

• If using RestTemplate, confirm you've configured converters for both JSON (sending) and plain/text (receiving):

  RestTemplate restTemplate = new RestTemplate();
  // Add JSON converter for sending payloads
  restTemplate.getMessageConverters().add(new MappingJackson2HttpMessageConverter());
  // Add plain/text converter for receiving responses
  restTemplate.getMessageConverters().add(new StringHttpMessageConverter(StandardCharsets.UTF_8));
  

• Make sure you're setting the correct request headers:

  HttpHeaders headers = new HttpHeaders();
  headers.setContentType(MediaType.APPLICATION_JSON);
  headers.setAccept(Collections.singletonList(MediaType.TEXT_PLAIN));
  HttpEntity<NewOrder> request = new HttpEntity<>(yourNewOrderObject, headers);
  

• If using WebClient, verify you've registered Jackson2JsonEncoder and StringDecoder properly.

Missing or conflicting dependencies can break JSON serialization/deserialization:

• Ensure you have core Jackson dependencies (if not using Spring Boot starters):

  implementation 'com.fasterxml.jackson.core:jackson-databind:2.15.2'
  implementation 'com.fasterxml.jackson.datatype:jackson-datatype-jsr310' // For Java 8+ date/time types
  

• If using Spring Boot, confirm spring-boot-starter-web is included (it bundles all necessary web and JSON handling dependencies)
• Check for version conflicts (use ./gradlew dependencies to inspect dependency trees)

Rule out API-side issues by testing outside your application:

• Use curl, Postman, or HTTPie to send a valid JSON payload and confirm you get a plain/text response:

  curl -X POST \
    https://your-api-endpoint.com/resource \
    -H "Content-Type: application/json" \
    -H "Accept: text/plain" \
    -d '{"field1":"value1", "field2":123}'
  

If this call fails, the problem lies with the API itself; if it works, the issue is in your Java client code.

内容的提问来源于stack exchange，提问作者Nital