import java.io.IOException;
import java.util.logging.FileHandler;
import java.util.logging.Formatter;
import java.util.logging.Level;
import java.util.logging.Logger;
import java.util.logging.SimpleFormatter;

public class Main {
  static Logger logger = Logger.getLogger("");

  static public void setupLogger() throws IOException {
    logger.setLevel(Level.ALL);
    FileHandler fileTxt = new FileHandler("log.txt");
    fileTxt.setFormatter(new SimpleFormatter());
    logger.addHandler(fileTxt);
  }

  static public void main() {
    logger.info("Hello World!");
  }
}