java date的一些操作

// DateUtil
// beginOfDay   endOfDay 获取当天的最早时间与最晚时间
// offsetDay 向前或向后推移几天，向前为负数，向后为正数
// cn.hutool.core.date.DateUtilprivate Long startTime;
private Long endTime;
startTime = DateUtil.beginOfDay(DateUtil.offsetDay(new Date(), 0)).getTime() / 1000;
endTime = DateUtil.endOfDay(DateUtil.offsetDay(new Date(), 0)).getTime() / 1000;-------------------------------------------------------------------------------------
// 获取当天，当周public static final String DATE_FORMAT_DAY_TIME = "yyyy-MM-dd HH:mm:ss";public static final String DATE_TYPE_WEEK = "week";public static final String DATE_TYPE_MONTH = "month";public static final String DATE_TYPE_YEAR = "year";public static final String DATE_TYPE_DAY = "day";public static  Map<String,String>  getTimeRange(String dateFormat,String dateType,Date date){Calendar calendar = Calendar.getInstance();calendar.setTime(date);calendar.setTimeZone(TimeZone.getTimeZone("GMT+8"));if("week".equals(dateType)){if (calendar.get(Calendar.DAY_OF_WEEK) == Calendar.SUNDAY) {calendar.add(Calendar.DAY_OF_YEAR,-1);}calendar.add(Calendar.DAY_OF_WEEK, -(calendar.get(Calendar.DAY_OF_WEEK) - 2));} else if ("month".equals(dateType)) {calendar.add(Calendar.MONTH, 0);calendar.set(Calendar.DAY_OF_MONTH, 1);} else if ("year".equals(dateType)) {calendar.add(Calendar.YEAR, 0);   // -1表示去年，0表示今年，1表示明年月，上下年份以此类型calendar.set(Calendar.DAY_OF_YEAR, calendar.getActualMinimum(Calendar.DAY_OF_YEAR));}calendar.set(Calendar.HOUR_OF_DAY, 0);calendar.set(Calendar.MINUTE, 0);calendar.set(Calendar.SECOND, 0);calendar.set(Calendar.MILLISECOND, 0);long startTime = calendar.getTimeInMillis();//end of the weekif("week".equals(dateType)){calendar.add(Calendar.DAY_OF_WEEK, 6);}else if ("month".equals(dateType)) {calendar.add(Calendar.MONTH, 1);calendar.set(Calendar.DAY_OF_MONTH, 0);}else if ("year".equals(dateType)) {calendar.add(Calendar.YEAR, 0);   // -1表示去年，0表示今年，1表示明年月，上下年份以此类型calendar.set(Calendar.DAY_OF_YEAR, calendar.getActualMaximum(Calendar.DAY_OF_YEAR));}calendar.set(Calendar.HOUR_OF_DAY, 23);calendar.set(Calendar.MINUTE, 59);calendar.set(Calendar.SECOND, 59);calendar.set(Calendar.MILLISECOND, 999);long endTime = calendar.getTimeInMillis();SimpleDateFormat format = new SimpleDateFormat(dateFormat);System.out.println(format.format(startTime));System.out.println(format.format(endTime));Map<String,String> map = new HashMap<>();map.put("startTime",format.format(startTime));map.put("endTime",format.format(endTime));return map;}