This example uses java.awt.Robot class to capture the screen pixels and returns a BufferedImage. Java.awt.Robot class is used to take the control of mouse and keyboard. Once you get the control , you can do any type of operation related to mouse and keyboard through your java code.
/* Copy and paste following code in your Java class and invoke the method captureScreen() with file name as argument. The screen shot will be stored in the file that you specified in argument. */ import java.awt.Dimension; import java.awt.Rectangle; import java.awt.Robot; import java.awt.Toolkit; import java.awt.image.BufferedImage; import javax.imageio.ImageIO; import java.io.File; // Method to capture images of your desktop in png format public void captureScreen(String fileName) throws Exception { Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize(); Rectangle screenRectangle = new Rectangle(screenSize); Robot robot = new Robot(); BufferedImage image = robot.createScreenCapture(screenRectangle); ImageIO.write(image, "png", new File(fileName)); }