import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;

import javax.swing.JFrame;
import javax.swing.JOptionPane;

public class Main {
		    public static void main(String[] args) throws IOException, InterruptedException {

		        ProcessBuilder p = new ProcessBuilder();

		        p.command("notepad.exe", "D:\\zapisy.txt");


		        FileInputStream fis=new FileInputStream("D:\\zapiswlaczony.txt");
		        int a=fis.read();
		        fis.close();
		        if((char)a=='0')
		        {
		        	FileOutputStream fos=new FileOutputStream("D:\\zapiswlaczony.txt");
				 fos.write('1');
				 fos.close();
		        Process notepad = p.start();
		        System.out.println("Start");

		        while(notepad.isAlive())
		        {


		        }
		        notepad.destroyForcibly();
		       FileOutputStream fos2=new FileOutputStream("D:\\zapiswlaczony.txt");
		        fos2.write('0');
		        System.out.println("End");
		    }
		        else
		        {
		        	JFrame frame = new JFrame("Informacja");
		        	JOptionPane.showMessageDialog(frame, "Zapis jest używany");
		        }
		}
}