open JFrame at center screen code example

Example 1: open jframe in center of screen

add this after setbounds

setLocationRelativeTo(null);

Example 2: open jframe in center of screen

Dimension dim = Toolkit.getDefaultToolkit().getScreenSize();
this.setLocation(dim.width/2-this.getSize().width/2, dim.height/2-this.getSize().height/2);