How to Resolve “Expected BEGIN_OBJECT but was BEGIN_ARRAY” in Android?

“Expected BEGIN_OBJECT but was BEGIN_ARRAY” is an error that occurs when trying to parse a JSON object in Android, but the JSON data being parsed is actually an array. This error can occur when the API endpoint being called is returning an array, but the code used to parse the response is expecting an object. To resolve this issue, you will need to modify the code to handle the array data properly. One popular library for parsing JSON in Android is GSON. Here is an example of how to use GSON to parse a JSON response and handle the “Expected BEGIN_OBJECT but was BEGIN_ARRAY” error:

Step by Step Solution

First, add the GSON library to your project by adding the following line to your app’s build.gradle file:

dependencies{ implementation ‘com.google.code.gson:gson:2.8.6’ }

Next, create a class that represents the JSON data in your response. For example, if the response is a list of user objects, you would create a User class.

public class User {

    private String name;

    private String email;

    // Add getters and setters for the properties

    // … }

Then in your activity or fragment, you can use the following code to parse the JSON response:

Java

// the json data you
// got from the API
String jsonData = ...;

Gson gson = new Gson();
try {
    User[] users = gson.fromJson(jsonData, User[].class);
}
catch (JsonSyntaxException e) {
    if (e.getMessage().equals(
            "Expected BEGIN_OBJECT but was BEGIN_ARRAY")) {
        JsonArray jsonArray = new JsonParser()
                                  .parse(jsonData)
                                  .getAsJsonArray();
        for (int i = 0; i < jsonArray.size(); i++) {
            User user = gson.fromJson(jsonArray.get(i),
                                      User.class);
            // do something with the user object
        }
    }
    else {
        // Handle other JSON parsing errors
    }
}

In this example, the code first attempts to parse the JSON data as an array of User objects using GSON. If the error “Expected BEGIN_OBJECT but was BEGIN_ARRAY” is thrown, the code then uses the JsonParser class to parse the JSON data as a JsonArray. The code then iterates through the JsonArray, parsing each element as a User object and adding it to a list. It’s important to note that this approach would work for a single-level JSON array, for the nested array you will have to use a different approach.

In conclusion, the “Expected BEGIN_OBJECT but was BEGIN_ARRAY” error can occur when trying to parse a JSON response in Android, but it can be easily resolved by modifying the code to handle the array data properly. One popular library for parsing JSON in Android is GSON, and the example above demonstrates how to use GSON to parse a JSON response and handle the error.