Java计算时间,可以像微信朋友圈那样显示发布的时间

/**
 * 日期处理工具类
 * 
 * @author whm
 *
 */
public class DateUtils {
public static final String YMD = "yyyyMMdd";
public static final String YMD_YEAR = "yyyy";
public static final String YMD_BREAK = "yyyy-MM-dd";
public static final String YMDHMS = "yyyyMMddHHmmss";
public static final String YMDHMS_BREAK = "yyyy-MM-dd HH:mm:ss";
public static final String YMDHMS_BREAK_HALF = "yyyy-MM-dd HH:mm";

/**
* 计算时间差
*/
public static final int CAL_MINUTES = 1000 * 60;
public static final int CAL_HOURS = 1000 * 60 * 60;
public static final int CAL_DAYS = 1000 * 60 * 60 * 24;

/**
* 获取当前时间格式化后的值
* 
* @param pattern
* @return
*/
public static String getNowDateText(String pattern){
SimpleDateFormat sdf = getSimpleDateFormat(pattern);
return sdf.format(new Date());
}

/**
* 获取日期格式化后的值
* 
* @param date
* @param pattern
* @return
*/
public static String getDateText(Date date, String pattern){
SimpleDateFormat sdf = getSimpleDateFormat(pattern);
return sdf.format(date);
}

/**
* 字符串时间转换成Date格式
* 
* @param date
* @param pattern
* @return
* @throws ParseException
*/
public static Date getDate(String date, String pattern) throws ParseException{
SimpleDateFormat sdf = getSimpleDateFormat(pattern);
return sdf.parse(date);
}

private static SimpleDateFormat getSimpleDateFormat(String pattern){
return new SimpleDateFormat(pattern);
}

/**
* 获取时间戳
* @param date
* @return
*/
public static Long getTime(Date date){
return date.getTime();
}

/**
* 计算时间差
* @param startDate
* @param endDate
* @param calType 计算类型,按分钟、小时、天数计算
* @return
*/
public static int calDiffs(Date startDate, Date endDate, int calType){
Long start = DateUtils.getTime(startDate);
Long end = DateUtils.getTime(endDate);
int diff = (int) ((end - start)/calType);
return diff;
}

/**
* 计算时间差值以某种约定形式显示
* 
* @param startDate
* @param endDate
* @return
*/
public static String timeDiffText(Date startDate, Date endDate){
int calDiffs = DateUtils.calDiffs(startDate, endDate, DateUtils.CAL_MINUTES);
if(calDiffs == 0){
return "刚刚";
}
if(calDiffs < 60){
return calDiffs + "分钟前";
}
calDiffs = DateUtils.calDiffs(startDate, endDate, DateUtils.CAL_HOURS);
if(calDiffs < 24){
return calDiffs + "小时前";
}
if(calDiffs < 48){
return "昨天";
}
return DateUtils.getDateText(startDate, DateUtils.YMDHMS_BREAK_HALF);
}

/**
* 显示某种约定后的时间值,类似微信朋友圈发布说说显示的时间那种
* 
* @param date
* @return
*/
public static String showTimeText(Date date){
return DateUtils.timeDiffText(date, new Date());
}

public static void main(String[] args) throws ParseException {
Date start = DateUtils.getDate("2017-07-05 10:54", DateUtils.YMDHMS_BREAK_HALF);
System.out.println(DateUtils.showTimeText(start));
}
}