NTerm
Needing a serial port communications program for a project, and not finding an open-source platform-independent version, Naroch undertook to create their own. NTerm is a fully functional program written using Java 10. In it, you can send ASCII messages to a serial port device, select baud rate, line ending characters, and even see messages sent from the end device in either ASCII or hexadecimal format.
This program is open source, so you can download the compiled version, or the source code to compile and edit it yourself. It is provided as-is under the Apache Software License Version 2.
To download the compiled version of NTerm, click here*
To download the NTerm source code, click here^
To use this program, you will need to download jSerialComm separately from http://fazecast.github.io/jSerialComm/