Contributed to the apache/dubbo repository by delivering targeted reliability and usability improvements in Java. Addressed resource management in streaming workflows by updating CompositeInputStream to ensure all underlying streams close properly, even when some close operations throw exceptions, and validated this behavior with comprehensive unit tests. Enhanced the CollectionUtils.toTreeSet API by introducing a comparator overload that improves type safety and gracefully handles null inputs, supported by additional null-coverage tests. Demonstrated skills in data structures, error handling, and unit testing, with a focus on code hygiene and robust API design. The work strengthened IO reliability and improved utility for custom sorting scenarios.