Java based astronomical logging software which stores it's data in a free and open XML based format (OpenAstronomyLog).
Impression is the flexible and extensible parser of mathematical expressions written in Java. It supports user defined operators, single or multi parameter functions and unlimited number of parameters. It is designed to use with numerical methods.
A Java class library - functional and easy-to-use classes for UI and more. You can learn a better way to work with UI trees while learning dotuseful. Open Source under the Apache License - use it with your commercial or non-commercial applications.