Ecco un tips su come fare uno screenshot in java e salvare il buffer dell'immagine in memoria su file in formato jpeg.

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import java.awt.image.*;
import java.awt.*;
import java.io.*;
import javax.imageio.*;

public class ScreenShot {
public static void main(String args[]) throws Exception {
Toolkit toolkit = Toolkit.getDefaultToolkit();
Dimension screenSize = toolkit.getScreenSize();
Rectangle screenRect = new Rectangle(screenSize);
Robot robot = new Robot();
BufferedImage image = robot.createScreenCapture(screenRect);
ImageIO.write(image, "jpg", new File("screenshot.jpg"));
}
}
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