java.awt.HeadlessException when trying to retrieve the screen width and height

[isaacmaffeis]

Code 1:

// single monitor configuration
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
screenWidth = screenSize.width;
screenHeight = screenSize.height;

Exception:

java.awt.HeadlessException
	at java.desktop/sun.awt.HeadlessToolkit.getScreenSize(HeadlessToolkit.java:186)
	at org.wallpaperwizardapp.wallpaperwizard.model.ImageResizer.screenSizeGetter(ImageResizer.java:88)
	at org.wallpaperwizardapp.wallpaperwizard.model.ImageResizer.resizeImage(ImageResizer.java:23)
	at org.wallpaperwizardapp.wallpaperwizard.Main.main(Main.java:42)

I have used this code for a multi-monitor configuration but the same exception comes back

Code 2:

// multi-monitor configuration
GraphicsDevice gd = GraphicsEnvironment.getLocalGraphicsEnvironment().getDefaultScreenDevice();
screenWidth = gd.getDisplayMode().getWidth();
screenHeight = gd.getDisplayMode().getHeight();

Exception:

java.awt.HeadlessException
	at java.desktop/sun.java2d.HeadlessGraphicsEnvironment.getDefaultScreenDevice(HeadlessGraphicsEnvironment.java:58)
	at org.wallpaperwizardapp.wallpaperwizard.model.ImageResizer.screenSizeGetter(ImageResizer.java:95)
	at org.wallpaperwizardapp.wallpaperwizard.model.ImageResizer.resizeImage(ImageResizer.java:23)
	at org.wallpaperwizardapp.wallpaperwizard.Main.main(Main.java:42)

I currently catch the exception and use the standard values of 1920 for the width and 1080 for the height