Creating animated transitions use to be a tedious task in Java Swing… until TimingFrameworks came along. TimingFrameworks (https://timingframework.dev.java.net/), written by Chet Haase, is a library for making Java animation and timing-based control easier. There are two good introductory articles on their website worth reading.
Crash course in animation
Below is the code to move a JFrame 100 pixels from left to right in 1 second.