how to implement the processing of events without creating a window

[Yuriy Paholkov]

Hello I am writing a program, take a screenshot by pressing F9. Processor keystrokes exists for JFrame, but how to do this handler without creating a window? Here code

    import java.awt.*;
import java.io.*;
import java.awt.image.*;
import javax.imageio.*;
import java.awt.event.*;
import javax.swing.*;
public class scrSshot extends JFrame{
   public static void main (String args[] ) throws Exception{
		JFrame s = new scrSshot();
		s.setVisible(true);
		s.addKeyListener(new KeyAdapter(){
	 public void keyPressed (KeyEvent e) {
     if (e.getKeyCode()==120){
	 try {
             Robot robot = new Robot();
            BufferedImage screenShot = robot.createScreenCapture(new Rectangle(Toolkit.getDefaultToolkit().getScreenSize()));
            ImageIO.write(screenShot, "JPG", new File("screenShot.jpg"));
	     } catch (Exception ex) {}
     }  
    }
	});	
	}
}  

[Darryl Burke]

You can't. At best, a command line application could process typed input AFTER the enter key is pressed to pass that input to your program.

Or look into JCurses (never used it nor taken a look at it myself).

[Yuriy Paholkov]

Thank you for your reply. Sorry for probably stupid question, but is it possible then to make a window invisible? does not turn into the tray, but it is invisible, but retaining the ability to process events?

[Darryl Burke]

No

[Rob Spoor]

Windows only process key and mouse events if that window is the active window. If it's invisible it will never be the active window.