字符串、时间类、日期类的相互转化

实现输入一个"yyyy-MM-dd hh:mm:ss"格式的字符串，输出向后推5分钟的格式化字符串

import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;
import java.util.GregorianCalendar;
public class 时间日期字符串大乱斗 {
	public static void main(String[] args) throws ParseException  {
		//时间类和字符串相互转化的格式
		DateFormat a = new SimpleDateFormat("yyyy-MM-dd hh:mm:ss");
		//目标字符串,也可以通过输入语句输入
		String data1 = "2018-09-13 10:10:00";
		//把字符串转化为时间类
		Date d = a.parse(data1);
		System.out.println(d); //Thu Sep 13 10:10:00 CST 2018
		//将时间类转化为格式化字符串
		String str = a.format(d);
		System.out.println(str); //2018-09-13 10:10:00
		Calendar b = new GregorianCalendar();
		//时间转化为日期类
		b.setTime(d);
		System.out.println(b);//java.util.GregorianCalendar[time=1536804600000,areFieldsSet=true,areAllFieldsSet=true,lenient=true,zone=sun.util.calendar.ZoneInfo[id="Asia/Shanghai",offset=28800000,dstSavings=0,useDaylight=false,transitions=19,lastRule=null],firstDayOfWeek=1,minimalDaysInFirstWeek=1,ERA=1,YEAR=2018,MONTH=8,WEEK_OF_YEAR=37,WEEK_OF_MONTH=3,DAY_OF_MONTH=13,DAY_OF_YEAR=256,DAY_OF_WEEK=5,DAY_OF_WEEK_IN_MONTH=2,AM_PM=0,HOUR=10,HOUR_OF_DAY=10,MINUTE=10,SECOND=0,MILLISECOND=0,ZONE_OFFSET=28800000,DST_OFFSET=0]
		//将时间向后推5分钟
		b.add(Calendar.MINUTE, 5);
		//将日期类转化为时间类
		Date date11 = b.getTime();
		//将时间类转化为格式化字符串
		String str1 = a.format(date11);
		System.out.println(str1); //2018-09-13 10:15:00
	}
}