Debugging JSON Serialization Issues in a Cross-Platform Java Mobile App with Gson
I'm collaborating on a project where Recently started working with a cross-platform mobile application using Java and the Gson library for JSON serialization. During testing, I noticed that some complex objects are not being serialized correctly, leading to missing data in the resulting JSON string. For instance, I have a class structure like this: ```java public class User { private String name; private int age; private List<Address> addresses; // Getters and Setters } public class Address { private String street; private String city; // Getters and Setters } ``` When I serialize a `User` object, I expect to see a JSON output containing the user’s name, age, and an array of addresses. However, the `addresses` field sometimes appears as `null`. ```java User user = new User(); user.setName("John Doe"); user.setAge(30); user.setAddresses(Arrays.asList(new Address("123 Elm St", "Springfield"))); Gson gson = new Gson(); String jsonOutput = gson.toJson(user); System.out.println(jsonOutput); ``` I tried adding `@Expose` annotations to the fields in the `User` class to ensure they are included in the serialization process, but it didn't seem to impact the output. Additionally, I've checked for any potential null values in the `addresses` list before serialization, yet I still encounter the same problem. The Gson version I’m using is 2.8.8, and I’m deploying this application to both Android and iOS platforms. What could be causing this serialization issue, and how can I ensure that all fields are included in the JSON output? Any insights on how to debug this effectively would be appreciated. I'd love to hear your thoughts on this.