Dev shares method to derive API data classes by reading JSON structure

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A developer writing for DEV Community admitted to incorrectly modeling data classes for a Pokédex app by inventing a server-vs-UI distinction that did not exist in the actual JSON. The core insight shared is that the number and shape of data classes should be determined entirely by the JSON response, not by assumptions. Each distinct curly-brace object in the JSON maps to one data class, while square brackets indicate a list type. The author outlines a step-by-step method: inspect the real API endpoint, count distinct object shapes, identify field types, and name classes after what they hold. Gson ignores undeclared fields, so developers only need to model the data their app actually uses.

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