一、一个月的开始与结束时间代码如下

/*** 获取指定月的开始日期* @param currentDate* @return*/public static Date getStartDate(String currentDate){SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");Calendar c = Calendar.getInstance();try {c.setTime(sdf.parse(currentDate));c.add(Calendar.MONTH, 0);//设置为1号,当前日期既为本月第一天c.set(Calendar.DAY_OF_MONTH, 1);} catch (ParseException e) {e.printStackTrace();}return c.getTime();}/*** 获取指定月的结束日期* @param currentDate* @return*/public static Date getEndDate(String currentDate){SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");Calendar c = Calendar.getInstance();try {c.setTime(sdf.parse(currentDate));c.set(Calendar.DAY_OF_MONTH, c.getActualMaximum(Calendar.DAY_OF_MONTH));c.set(Calendar.HOUR_OF_DAY, 23);c.set(Calendar.MINUTE, 59);c.set(Calendar.SECOND, 59);} catch (ParseException e) {e.printStackTrace();}return c.getTime();}

二、两个日期相差几个月

/*** 获取两个日期相差几个月* @param start* @param end* @return*/public static int getMonth(Date start, Date end) {if (start.after(end)) {Date t = start;start = end;end = t;}Calendar startCalendar = Calendar.getInstance();startCalendar.setTime(start);Calendar endCalendar = Calendar.getInstance();endCalendar.setTime(end);Calendar temp = Calendar.getInstance();temp.setTime(end);temp.add(Calendar.DATE, 1);int year = endCalendar.get(Calendar.YEAR) - startCalendar.get(Calendar.YEAR);int month = endCalendar.get(Calendar.MONTH) - startCalendar.get(Calendar.MONTH);if ((startCalendar.get(Calendar.DATE) == 1)&& (temp.get(Calendar.DATE) == 1)) {return year * 12 + month + 1;} else if ((startCalendar.get(Calendar.DATE) != 1) && (temp.get(Calendar.DATE) == 1)) {return year * 12 + month;} else if ((startCalendar.get(Calendar.DATE) == 1) && (temp.get(Calendar.DATE) != 1)) {return year * 12 + month;} else {return (year * 12 + month - 1) < 0 ? 0 : (year * 12 + month);}}

三、测试代码

public static void main(String[] args) throws ParseException{SimpleDateFormat sdf = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss");String startDate = "-10-15 00:00:00";String ednDate = "-11-10 23:59:59";Date sdate = getStartDate(startDate);Date edate = getEndDate(startDate);System.out.println("开始时间：" + sdf.format(sdate));System.out.println("结束时间：" + sdf.format(edate));int month = getMonth(sdf.parse(startDate), sdf.parse(ednDate));System.out.println("两者之间相差：" + month);}