Java Data Type - 如何设置精度修改器，在字符串中最多显示15个字符

import java.util.Formatter;

public class MainClass {
  public static void main(String args[]) {
    Formatter fmt = new Formatter();

    fmt.format("%.15s", "Formatting with Java is now easy.");
    System.out.println(fmt);
  }
}