SizedFrameTest.java

package sizedFrame;

import javax.swing.*;
import java.awt.*;

/**
 * @author Cay Horstmann
 * @version 1.34 2015-06-16
 */
public class SizedFrameTest {
    public static void main(String[] args) {
        EventQueue.invokeLater(() -> {
            JFrame frame = new SizedFrame();
            frame.setTitle("SizedFrame");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.setVisible(true);
        });
    }
}

class SizedFrame extends JFrame {
    public SizedFrame() {
        // get screen dimensions

        Toolkit kit = Toolkit.getDefaultToolkit();
        Dimension screenSize = kit.getScreenSize();
        int screenHeight = screenSize.height;
        int screenWidth = screenSize.width;

        // set frame width, height and let platform pick screen location

        setSize(screenWidth / 2, screenHeight / 2);
        setLocationByPlatform(true);

        // set frame icon

        // Image img = new ImageIcon("icon.gif").getImage();
        Image img = new ImageIcon(ClassLoader.getSystemResource("icon.gif")).getImage();
        setIconImage(img);
    }
}