Spring Boot REST API: Handling Nested JSON Objects with Variable Key Names
I recently switched to I'm converting an old project and I've been researching this but I've been banging my head against this for hours. I recently switched to I'm updating my dependencies and I'm developing a REST API using Spring Boot (version 2.5.4) that needs to handle a complex JSON payload with nested objects containing variable key names..... The payload looks like this: ```json { "userId": 123, "details": { "preferences": { "theme": "dark", "language": "en" }, "data": { "2022-01-01": { "value": 50 }, "2022-01-02": { "value": 75 } } } } ``` I've created a DTO to represent the incoming request: ```java public class UserDetails { private int userId; private Details details; // Getters and Setters } public class Details { private Preferences preferences; private Map<String, DataValue> data; // Getters and Setters } public class Preferences { private String theme; private String language; // Getters and Setters } public class DataValue { private int value; // Getters and Setters } ``` Despite this setup, when I try to send a POST request to `/api/users`, I'm getting a `400 Bad Request` behavior with the message `want to deserialize value of type ... from Object value (token JsonToken.START_OBJECT)`. It seems like the `data` field, which is a map with variable keys, is causing the scenario. I've also added the necessary `@RequestBody` annotation in my controller: ```java @PostMapping("/api/users") public ResponseEntity<?> createUserDetails(@RequestBody UserDetails userDetails) { // Logic to process userDetails return ResponseEntity.ok().build(); } ``` I even tried using `@JsonAnySetter` in the `Details` class to accommodate the variable keys, but I still get the same behavior. Could the scenario be with how I'm structuring the DTO, or is there a configuration in my Spring Boot application that can help with deserializing this nested structure correctly? Any insights would be appreciated! My development environment is macOS. Thanks in advance! Any ideas what could be causing this? Could someone point me to the right documentation? For context: I'm using Java on Windows 10. Thanks for any help you can provide! My development environment is Windows 10. Has anyone dealt with something similar? The project is a service built with Java. Has anyone dealt with something similar?