Java Data Type - 如何获取秒数值的最多6位精度的时间

import java.sql.Timestamp;
import java.text.DateFormat;
import java.text.DecimalFormat;
import java.text.NumberFormat;
import java.text.SimpleDateFormat;
import java.util.Date;


public class Main {

  public static void main(String[] args) {
    long time = System.currentTimeMillis();
    Date d = new Date(time);
    Timestamp t = new Timestamp(time);
    t.setNanos(123456789);
    System.out.println(d);
    System.out.println(t);
    DateFormat df = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss'.'");
    NumberFormat nf = new DecimalFormat("000000000");
    System.out.println(df.format(t.getTime()) + nf.format(t.getNanos()));
  }
}