Developed a comprehensive test suite for the AuthorizationQueryDto component in the operaton/operaton repository, focusing on validating filter and sort parameter handling to reinforce the robustness of authorization query logic. Leveraged Java, JUnit, and Mockito to implement AuthorizationQueryDtoTest, ensuring both provided and missing values were thoroughly covered. This disciplined approach to unit testing enhanced regression safety by verifying edge-case behaviors and clarified expectations for future development. The work improved maintainability and future-proofing of the authorization module, supporting backend development best practices and reducing the risk of regressions in critical query logic through expanded and targeted DTO test coverage.