Java Data Type - 如何simpleDateFormat格式：2013-05-16 09：35：31.0

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;

public class Main {

  public static void main(String[] args) {

    String str_date = "2015-05-15 05:55:55.0";
    DateFormat formatter;
    Date date;
    try {
      formatter = new SimpleDateFormat("yyyy-MM-d HH:mm:ss");
      date = formatter.parse(str_date);
      System.out.println(date);
    } catch (ParseException e) {
      e.printStackTrace();
    }

  }
}