//write in file
 try {
      File myObj = new File("filename.txt");
      if (myObj.createNewFile()) {
        System.out.println("File created: " + myObj.getName());
      } else {
        System.out.println("File already exists.");
      }

    } catch (IOException e) {
      System.out.println("An error occurred.");
      e.printStackTrace();
    }
//read from file