Why Does GSON Throw 'Expected BEGIN_OBJECT but was BEGIN_ARRAY'?

GSON Throws "Expected BEGIN_OBJECT but was BEGIN_ARRAY" Error

In attempting to parse a JSON string containing an array of objects into a list of objects, GSON throws a "Expected BEGIN_OBJECT but was BEGIN_ARRAY" exception. The issue lies in the expectation mismatch between the JSON structure and the code's attempt to interpret it.

To understand the error, consider the JSON string:

[
   {
      // Object properties
   },
   {
      // Another object
   }
]

This JSON represents an array of objects. However, the code attempts to deserialize it as a single object of type ChannelSearchEnum. This expectation mismatch leads to the error.

To resolve this issue, correct the code to expect an array of objects:

Gson gson = new Gson();
ChannelSearchEnum[] enums = gson.fromJson(yourJson, ChannelSearchEnum[].class);

Alternatively, you can use the TypeToken class to create a type that represents the collection of objects:

Type collectionType = new TypeToken<Collection<ChannelSearchEnum>>(){}.getType();
Collection<ChannelSearchEnum> enums = gson.fromJson(yourJson, collectionType);

By correctly handling the JSON structure, you can avoid the "Expected BEGIN_OBJECT but was BEGIN_ARRAY" error and successfully parse and use the data.

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