import java.io.FileWriter;
import java.io.PrintWriter;
import java.util.Calendar;
public class Main {
static void timeStamp(String msg, PrintWriter pw) {
Calendar cal = Calendar.getInstance();
pw.printf("%s %tc\n", msg, cal);
}
public static void main(String args[]) throws Exception {
PrintWriter pw = new PrintWriter(new FileWriter("logfile.txt", true));
timeStamp("File opened", pw);
pw.close();
if (pw.checkError())
System.out.println("I/O error occurred.");
}
}