Worked on enhancing the reliability of query cancellation for spatial property functions in the apache/jena repository. Addressed a bug by implementing lazy iterator creation and refactoring both NiceIterator and GenericPropertyFunction to ensure iterators are properly closed when queries are canceled, reducing the risk of resource leaks and inconsistent states. Developed CancelQueryTest to comprehensively validate cancellation behavior under various scenarios, thereby expanding test coverage for these cases. Utilized Java and the Jena API, with a focus on iterator management, query optimization, and SPARQL. This work improved the robustness and maintainability of spatial function support within the codebase.