格式化日期

--使用Date

import java.util.Date;

import java.text.SimpleDateFormat;

Date d = new Date();

SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");

System.out.println("当前时间：" + sdf.format(d));

 ** 可选日期格式 yyyy-MM-dd HH:mm:ss, yyyy-MM-dd, HH:mm:ss

--使用Calendar

    Calendar calendar = Calendar.getInstance();

    System.out.println("年：" + calendar.get(Calendar.YEAR));

    System.out.println("月：" + (calendar.get(Calendar.MONTH) + 1));

    System.out.println("日：" + calendar.get(Calendar.DAY_OF_MONTH));

    System.out.println("时：" + calendar.get(Calendar.HOUR_OF_DAY));

    System.out.println("分：" + calendar.get(Calendar.MINUTE));

    System.out.println("秒：" + calendar.get(Calendar.SECOND));

--使用Calendar格式化指定日期

   Calendar calendar = Calendar.getInstance();

   Date date = new Date();

   calendar.setTime(date);

   System.out.println("年：" + calendar.get(Calendar.YEAR));

    System.out.println("月：" + (calendar.get(Calendar.MONTH) + 1));

    System.out.println("日：" + calendar.get(Calendar.DAY_OF_MONTH));

    System.out.println("时：" + calendar.get(Calendar.HOUR_OF_DAY));

    System.out.println("分：" + calendar.get(Calendar.MINUTE));

    System.out.println("秒：" + calendar.get(Calendar.SECOND));