Here is the java GUI I did for my own Arduino project

The code you will find under src if you want to use this

For those who know how to use git hub this is quite simple

git clone https://github.com/markh2016/JavaSerialPort.git

After cloning of you go to the distribution folder you will find the application jar file

To run the project from the command line, type the following:

java -jar "SerialPort.jar"

You can import the full net beans project into your net beans ide make any adjustments you may want to do yourselves

The full net beans project includes the JSerialComport jar file and is contained on this site