Capture the Screen with Java’s Robot Class

Java’s Robot class makes it really easy to capture the screen as an image. Here, we’ll take a screenshot using the dimensions of the user’s screen resolution, show the image in a JFrame, and save it to disk as a GIF.

The Code

import java.awt.Dimension;
import java.awt.Rectangle;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.io.File;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JFrame;
import javax.swing.JLabel;

public class SimpleScreenCapture {

	/**
	 * @param args
	 */
	public static void main( String[] args ) throws Exception {

		// Make a rectangle according to the size of the screen

		Rectangle rectangle = new Rectangle( Toolkit.getDefaultToolkit().getScreenSize() );

		// Initialize a JFrame where we will show the image

		JFrame frame = new JFrame();
		frame.setDefaultCloseOperation( JFrame.EXIT_ON_CLOSE );

		// Take the screenshot

		Robot robot = new Robot();
		BufferedImage img = robot.createScreenCapture( rectangle );

		// Use a JLabel icon to display the image

		frame.add( new JLabel( new ImageIcon( img ) ) );
		frame.pack();
		frame.setVisible( true );

		// Save the image as a GIF to disk

		File file = new File( "screenshot.gif" );
		ImageIO.write( img, "gif", file );

	}

}