Java 时间转换

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

/**
 * Created by Edward on 2016/6/30.
 */
public class TimeUtil {


    /**
     * 将 1467341232351 转换为 指定格式 "yyyy-MM-dd HH:mm:ss.SSS"
     * @param time        "1467342217645"
     * @param pattern     "yyyy-MM-dd HH:mm:ss.SSS"
     * @return            2016-07-01 11:03:37.645
     */

    public static String parseLongTime2String(String time, String pattern){
        Calendar calendar = Calendar.getInstance();
        calendar.setTimeInMillis(Long.valueOf(time));
        return new SimpleDateFormat(pattern).format(calendar.getTime());
    }


    /**
     * 将指定格式的字符串转化为long
     * @param time   "2016-07-01 10:52:41.792"
     * @param pattern "yyyy-MM-dd HH:mm:ss.SSS"
     * @return         1467341561792
     */
    public static long parseString2LongTime(String time, String pattern)
    {
        Date date = null;
        try {
            date = new SimpleDateFormat(pattern).parse(time);
        } catch (ParseException e) {
            e.printStackTrace();
        }
        return date.getTime();
    }

    /**
     *
     * @param time     "2016-07-01 10:52:41.792"
     * @param pattern  "yyyy-MM-dd HH:mm:ss.SSS"
     * @param info     "YEAR"
     * @return          2016
     */
    public static int parseString2SpecialInfo(String time, String pattern, String info)
    {
        Date date = null;
        try {
            date = new SimpleDateFormat(pattern).parse(time);
            Calendar c = Calendar.getInstance();
            c.setTime(date);
            if(info.equals("YEAR"))
            {
                return c.get(Calendar.YEAR);
            }
            else if(info.equals("MONTH"))
            {
                return c.get(Calendar.MONTH)+1;
            }
            else if(info.equals("DAY"))
            {
                return c.get(Calendar.DAY_OF_MONTH);
            }
            else if(info.equals("HOUR"))
            {
                return c.get(Calendar.HOUR_OF_DAY);
            }
            else if(info.equals("MINUTE"))
            {
                return c.get(Calendar.MINUTE);
            }
            else if(info.equals("SECOND"))
            {
                return c.get(Calendar.SECOND);
            }
            else if(info.equals("MILLISECOND"))
            {
                return c.get(Calendar.MILLISECOND);
            }
            else
            {
                return -1;
            }
        } catch (ParseException e) {
            e.printStackTrace();
        }
        return -1;
    }




    public static void main(String[] args)
    {
        Calendar calendar = Calendar.getInstance();

        System.out.println(calendar.getTimeInMillis());

        System.out.println(TimeUtil.parseLongTime2String(String.valueOf(calendar.getTimeInMillis()),"yyyy-MM-dd HH:mm:ss.SSS"));

        System.out.println(TimeUtil.parseString2LongTime("2016-07-01 10:52:41.792","yyyy-MM-dd HH:mm:ss.SSS"));

        int year = TimeUtil.parseString2SpecialInfo("2016-07-01 10:52:41.792","yyyy-MM-dd HH:mm:ss.SSS","YEAR");
        int month = TimeUtil.parseString2SpecialInfo("2016-07-01 10:52:41.792","yyyy-MM-dd HH:mm:ss.SSS","MONTH");
        int day = TimeUtil.parseString2SpecialInfo("2016-07-01 10:52:41.792","yyyy-MM-dd HH:mm:ss.SSS","DAY");

        System.out.println("Year:"+year+",Month:"+month+",Day:"+day);
    }

}