Beyond the sequence of examples provided here, the Logisim source code provides copious additional examples, though they do not always illustrate the same attention to readability and good design.
For maximum portability to future versions, you should stick as much as possible to the classes in the ...instance, ...data, and ...tools packages. Of course, you may use other packages' APIs, but they are more vulnerable to changes in future versions of Logisim.
You can post your questions or suggestions for improvement on the Logisim-evolution website. Your comments are always welcome.
You are free to distribute any JARs you develop without restriction. The GPL restrictions do apply, however, if portions of your work are derived from portions of Logisim source code (released under the GPL). Deriving from the example code in this section of the User's Guide does not incur such restrictions; these examples are released under the MIT license.
Contact the administrators of the Logisim-evolution website if you'd like to share your libraries with other users or help develop this software.
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