//use only if the component is visible on the screen.
//It returns buffered images that do not support transparent pixels.
import java.awt.image.BufferedImage;
import javax.swing.JFrame;
public class Main {
public static void main(String[] argv) throws Exception {
JFrame f = new JFrame();
f.setVisible(true);
int width = 300;
int height = 500;
BufferedImage bimage = (BufferedImage) f.createImage(width, height);
if (bimage == null) {
System.out.println("component is not visible on the screen");
}
}
}