Java tutorial
//package com.java2s; import java.awt.Dimension; import java.awt.Point; import java.awt.Toolkit; public class Main { /** * Returns a <code>Point</code> used as location for a window that * should be centered on the screen. * * @param size a <code>Dimension</code> describing the window's size * @return a <code>Point</code> describing the top-left position */ public static Point getCenteredLocation(Dimension size) { final Toolkit tk = Toolkit.getDefaultToolkit(); final Dimension screenSize = tk.getScreenSize(); return new Point(((screenSize.width - size.width) / 2), ((screenSize.height - size.height) / 2)); } }