Worked on enhancing the Azure/azure-sdk-for-java repository by delivering comprehensive unit test coverage for the MultipartFormDataHelper component. Focus centered on validating the serialization of JSON fields, robust handling of null values, and support for multi-file uploads with diverse content types and filenames, all to ensure correct multipart/form-data formatting for API interactions. Leveraged Java and unit testing frameworks to systematically verify payload construction, reducing the risk of regressions and supporting upcoming API changes. This effort improved SDK reliability and release stability, with a technical emphasis on API integration and thorough test-driven validation rather than direct bug fixes during the development period.