Simple measurement gui to practice Java Swing. The program is made in JDK 11, so you should use 11+ to run it.
A frame holds 5 tabs, one for length, mass, volume, and temperature. Each tab has two comboboxes and two text fields, one row for input and the other for output. The input can be that of real positive numbers, either in normal or scientific notation. Once the input is done, press the convert button for the final conversion.