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implementing Custom Deserialization of Nested JSON Objects Using Jackson in Spring Boot 2.5

👀 Views: 88 đŸ’Ŧ Answers: 1 📅 Created: 2025-07-14
java spring-boot jackson Java

Does anyone know how to I'm relatively new to this, so bear with me. I'm having trouble with custom deserialization of a nested JSON object in my Spring Boot application using Jackson. The JSON structure looks like this: ```json { "user": { "id": 1, "name": "John Doe", "address": { "street": "123 Main St", "city": "Anytown" } } } ``` I created the following classes to represent the structure: ```java public class User { private int id; private String name; private Address address; // Getters and Setters } public class Address { private String street; private String city; // Getters and Setters } ``` However, when I attempt to deserialize the JSON using the following code: ```java ObjectMapper objectMapper = new ObjectMapper(); User user = objectMapper.readValue(jsonString, User.class); ``` I receive the following behavior: ``` com.fasterxml.jackson.databind.exc.InvalidDefinitionException: want to construct instance of `User` (no Creator, default constructor, or no properties); nested exception is com.fasterxml.jackson.databind.JsonMappingException: No content to map due to end-of-input ``` I ensured that my classes have default constructors and public getters/setters. I also checked the JSON string to confirm that it's not empty. I tried adding annotations like `@JsonCreator` and `@JsonProperty` but I still face the same scenario. I've verified that the Jackson dependencies are correct in my `pom.xml`: ```xml <dependency> <groupId>com.fasterxml.jackson.core</groupId> <artifactId>jackson-databind</artifactId> <version>2.12.3</version> </dependency> ``` Is there something I'm missing with the deserialization process for nested objects? Any insights would be greatly appreciated. This is part of a larger application I'm building. Is there a better approach? I'm working with Java in a Docker container on Windows 10.