In the dark days of the late ’90s there was the idea that Swing is slow. It may have been back then. Today, Java2D is screamingly fast, and that is what Swing is based on. So, as programmers, we are out of excuses for creating poorly performing Graphical User Interface (GUI) applications.
The main arbiter of performance in a NetBeans-based application is memory usage. The first step anyone can take toward optimizing their code is to avoid using any memory until something really needs to be done, and then be efficient about what information needs to be kept around.
The second arbiter of performance in a NetBeans-based application is class loading. Class objects take up memory. In a Java VM, a
Class object is a byte array. ...