👀 Views: 86 💬 Answers: 1 📅 Created: 2025-06-13

spring-mvc json jackson httpmessage Java

I'm having a hard time understanding Quick question that's been bugging me - I'm working with an `HttpMessageNotReadableException` when trying to send a nested object as `@RequestBody` in my Spring MVC application..... I'm using Spring 5.3.10 and Jackson for JSON serialization/deserialization. My endpoint looks like this: ```java @PostMapping("/api/users") public ResponseEntity<User> createUser(@RequestBody User user) { userService.save(user); return ResponseEntity.status(HttpStatus.CREATED).body(user); } ``` The `User` class has fields like `name`, `email`, and a nested `Address` object: ```java public class User { private String name; private String email; private Address address; // getters and setters } public class Address { private String street; private String city; // getters and setters } ``` When I send the following JSON payload: ```json { "name": "John Doe", "email": "john@example.com", "address": { "street": "123 Elm St", "city": "Metropolis" } } ``` I receive the behavior: ``` org.springframework.http.converter.HttpMessageNotReadableException: JSON parse behavior: Unexpected character ('n' (code 110)): was expecting double-quote to start field name at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 1, column: 2] (through reference chain: User["name"]) ``` I've checked my JSON syntax, and it seems correct. I've also added the necessary annotations to the `User` and `Address` classes, ensuring they have proper getters and setters. I tried using `@JsonProperty` to explicitly define field names, but that didn't resolve the scenario. Additionally, I verified that my Jackson configuration is correct and that it's included in the project dependencies. The scenario continues when I use Postman and also when I test with a simple cURL command. Am I missing something in the configuration, or is there something specific about the JSON format I need to address? I'm working on a application that needs to handle this. What's the correct way to implement this? What are your experiences with this?