import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Calendar;
import java.util.Date;public class DateUtil {/*** 比较日期大小* @param dateStr0* @param dateStr1* @return*/public static int compareDate(String dateStr0, String dateStr1) {Date date1 = convertDateStrToDate(dateStr0, "datetime");Date date2 = convertDateStrToDate(dateStr1, "datetime");int result = date1.compareTo(date2);return result;}/*** 格式化日期* @param date* @param pattern*       "date":返回日期(yyyy-MM-dd)*      "time":返回时间(HH:mm:ss)*        "datetime":返回日期和时间(yyyy-MM-dd HH:mm:ss)* @return*/public static String formatDate(Date date, String pattern) {if (date == null) {return "";}if ("date".equals(pattern)) {pattern = "yyyy-MM-dd";} else if ("time".equals(pattern)) {pattern = "HH:mm:ss";} else if ("datetime".equals(pattern)) {pattern = "yyyy-MM-dd HH:mm:ss";}SimpleDateFormat formatter = new SimpleDateFormat(pattern);return formatter.format(date);}/*** 格式化日期字符串* @param dateStr* @param type*        "date":返回日期(yyyy-MM-dd)*      "time":返回时间(HH:mm:ss)*        "datetime":返回日期和时间(yyyy-MM-dd HH:mm:ss)* @return*/public static String formatDate(String dateStr, String type) {if (dateStr == null || "".equals(dateStr.trim())) {return "";}DateFormat formatter = DateFormat.getDateInstance();Date date = null;try {date = formatter.parse(dateStr);} catch (ParseException e) {e.printStackTrace();}return formatDate(date, type);}/*** 把日期字符串转换成日期* @param dateStr*      日期字符串* @param pattern*         "date":日期,*       "datetime":日期和时间* @return*/public static Date convertDateStrToDate(String dateStr, String pattern) {if (dateStr == null || "".equals(dateStr.trim())) {return null;}if (!dateStr.contains(":")) {dateStr += " 00:00:00";}if ("date".equals(pattern)) {pattern = "yyyy-MM-dd";} else if ("datetime".equals(pattern)) {pattern = "yyyy-MM-dd HH:mm:ss";}SimpleDateFormat formatter = new SimpleDateFormat(pattern);Date date = null;try {date = formatter.parse(dateStr);} catch (ParseException e) {e.printStackTrace();}return date;}/*** 获取当前时间* @return*/public static Date getCurrTime() {return new Date();}/*** 获取当前时间* @param pattern*        "date":返回日期(yyyy-MM-dd),*         "time":返回时间(HH:mm:ss),*       "datetime":返回日期和时间(yyyy-MM-dd HH:mm:ss)* @return*/public static String getCurrTime(String pattern) {return formatDate(new Date(), pattern);}/*** 获取中文格式当前日期* @param pattern*        "long":1984年10月9日*        "full":1984年10月9日 星期二* @return*/public static String getCurrDateCN(String pattern) {Calendar calendar = Calendar.getInstance();int year = calendar.get(Calendar.YEAR);int month = calendar.get(Calendar.MONTH) + 1;int day = calendar.get(Calendar.DAY_OF_MONTH);if ("long".equals(pattern)) {return year + "年" + month + "月" + day + "日";}if ("full".equals(pattern)) {return year + "年" + month + "月" + day + "日 " + getDayCN(calendar.getTime());}return "";}/*** 在原日期加一段时间间隔* @param date*        原日期* @param field*         "yyyy":年*         "MM":月*       "dd":日* @param amount*       间隔长度* @return*/public static Date dateAdd(Date date, String field, int amount) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);if ("yyyy".equals(field)) {calendar.add(Calendar.YEAR, amount);} else if ("MM".equals(field)) {calendar.add(Calendar.MONTH, amount);} else if ("dd".equals(field)) {calendar.add(Calendar.DATE, amount);}return calendar.getTime();}/*** 在原日期加一段时间间隔* @param date*       原日期* @param field*         "yyyy":年*         "MM":月*       "dd":日* @param amount*       间隔长度* @param pattern*      "date":返回日期(yyyy-MM-dd),*         "time":返回时间(HH:mm:ss),*       "datetime":返回日期和时间(yyyy-MM-dd HH:mm:ss)* @return*/public static String dateAdd(String dateStr, String field, int amount, String pattern) {if (Tools.isEmpty(dateStr)) {return "";}Date date = convertDateStrToDate(dateStr, "datetime");Calendar calendar = Calendar.getInstance();calendar.setTime(date);if ("yyyy".equals(field)) {calendar.add(Calendar.YEAR, amount);} else if ("MM".equals(field)) {calendar.add(Calendar.MONTH, amount);} else if ("dd".equals(field)) {calendar.add(Calendar.DATE, amount);}date = calendar.getTime();dateStr = formatDate(date, pattern);return dateStr;}/*** 计算日期差* @param date1* @param date2* @param field*      yyyy:年*         MM:月*       dd:日* @return*         date2 - date1*/public static int dateDiff(Date date1, Date date2, String field) {boolean flag = date1.compareTo(date2) > 0;if (flag) {Date tmp = date1;date1 = date2;date2 = tmp;}Calendar cal1 = Calendar.getInstance();cal1.setTime(date1);int year1 = cal1.get(Calendar.YEAR);int month1 = cal1.get(Calendar.MONTH);Calendar cal2 = Calendar.getInstance();cal2.setTime(date2);int year2 = cal2.get(Calendar.YEAR);int month2 = cal2.get(Calendar.MONTH);int yearDiff = year2- year1;int diff = 0;if ("yyyy".equals(field)) {diff = yearDiff;} else if ("MM".equals(field)) {if (yearDiff <= 0) {diff = month2 - month1;} else if (yearDiff == 1) {diff = 12 - month1 + month2;} else {diff = 12 - month1 + (year2 - year1 - 1) * 12 + month2;}} else if ("dd".equals(field)) {if (yearDiff <= 0) {diff = cal2.get(Calendar.DAY_OF_YEAR) - cal1.get(Calendar.DAY_OF_YEAR);} else if (yearDiff == 1) {diff = getDaysLeftOfYear(date1) + cal2.get(Calendar.DAY_OF_YEAR);} else {diff = getDaysLeftOfYear(date1);Calendar cal;for (int i = 1; i < yearDiff; i++) {cal = Calendar.getInstance();cal.setTime(dateAdd(date1, "yyyy", i));diff += cal.getActualMaximum(Calendar.DAY_OF_YEAR);}diff += cal2.get(Calendar.DAY_OF_YEAR);}}return flag ? -1 * diff : diff;}/*** 计算日期差* @param date1* @param date2* @param field*        yyyy:年*         MM:月*       dd:日* @return*/public static int dateDiff(String dateStr1, String dateStr2, String field) {Date date1 = convertDateStrToDate(dateStr1, "date");Date date2 = convertDateStrToDate(dateStr2, "date");int dateDiff = dateDiff(date1, date2, field);return dateDiff;}/*** 是否闰年* @param year* @return*/public static boolean isLeapYear(int year) {boolean flag = (year % 4 == 0 && year % 100 != 0) || year % 400 == 0;return flag;}/*** 是否闰年* @param date* @return*/public static boolean isLeapYear(Date date) {Calendar cal = Calendar.getInstance();cal.setTime(date);boolean flag = isLeapYear(cal.get(Calendar.YEAR));return flag;}/*** 计算给定日期当年总天数* @param date* @return*/public static int getDaysOfYear(Date date) {Calendar cal = Calendar.getInstance();cal.setTime(date);return cal.getActualMaximum(Calendar.DAY_OF_YEAR);}/*** 计算给定日期当年剩余天数* @param date* @return*/public static int getDaysLeftOfYear(Date date) {Calendar cal = Calendar.getInstance();cal.setTime(date);int cnt = cal.getActualMaximum(Calendar.DAY_OF_YEAR) - cal.get(Calendar.DAY_OF_YEAR);return cnt;}/*** 获得星期几(周日为1，周六为7)* @param date*        给定日期* @return*/public static int getDay(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);return calendar.get(Calendar.DAY_OF_WEEK);}/*** 获得星期几（中文）* @param date* @return*/public static String getDayCN(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);switch (dayOfWeek) {case 1:return "星期日";case 2:return "星期一";case 3:return "星期二";case 4:return "星期三";case 5:return "星期四";case 6:return "星期五";case 7:return "星期六";default:return "";}}/*** 计算给定日期所在月的第一天* @param date*         给定日期* @return*/public static Date getFirstDayOfMonth(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);calendar.set(Calendar.DAY_OF_MONTH, 1);return calendar.getTime();}/*** 计算给定日期所在月的最后一天* @param date*       给定日期* @return*/public static Date getLastDayOfMonth(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);calendar.set(Calendar.DAY_OF_MONTH, calendar.getActualMaximum(Calendar.DAY_OF_MONTH));return calendar.getTime();}/*** 计算给定日期所在周的第一天(周一)* @param date*      给定日期* @return*/public static Date getFirstDayOfWeek(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);dayOfWeek = dayOfWeek == Calendar.SUNDAY ? 8 : dayOfWeek;int dValue = Calendar.MONDAY - dayOfWeek;calendar.add(Calendar.DAY_OF_WEEK, dValue);return calendar.getTime();}/*** 计算给定日期所在月的最后一天(周日)* @param date*      给定日期* @return*/public static Date getLastDayOfWeek(Date date) {Calendar calendar = Calendar.getInstance();calendar.setTime(date);int dayOfWeek = calendar.get(Calendar.DAY_OF_WEEK);dayOfWeek = dayOfWeek == Calendar.SUNDAY ? 8 : dayOfWeek;int diff = 8 - dayOfWeek;calendar.add(Calendar.DAY_OF_WEEK, diff);return calendar.getTime();}/*** 计算月视图中展示的第一天* @param date*       给定日期* @return*/public static Date getFirstDayOfMonthView(Date date) {Date firstDayOfMonth = getFirstDayOfMonth(date);int dayOfWeek = getDay(firstDayOfMonth);int diff = Calendar.SUNDAY - dayOfWeek;Calendar calendar = Calendar.getInstance();calendar.setTime(firstDayOfMonth);calendar.add(Calendar.DAY_OF_WEEK, diff);return calendar.getTime();}/*** 计算月视图中展示的最后一天* @param date*         给定日期* @return*/public static Date getLastDayOfMonthView(Date date) {Date lastDayOfMonth = getLastDayOfMonth(date);int dayOfWeek = getDay(lastDayOfMonth);int diff = Calendar.SATURDAY - dayOfWeek;Calendar calendar = Calendar.getInstance();calendar.setTime(lastDayOfMonth);calendar.add(Calendar.DAY_OF_WEEK, diff);return calendar.getTime();}/*** 计算月视图展示行数* @param date* @return*/public static int getRowCntOfMonthView(Date date) {int dayOfWeek1 = getDay(getFirstDayOfMonth(date));int dayOfWeek2 = getDay(getLastDayOfMonth(date));if (dayOfWeek1 == Calendar.SUNDAY && dayOfWeek2 == Calendar.SATURDAY) {return 4;}if (dayOfWeek1 != Calendar.SUNDAY && dayOfWeek2 != Calendar.SATURDAY) {return 6;}return 5;}public static void main(String args[]) {System.out.println(DateUtil.getCurrDateCN("full"));System.out.println(DateUtil.getCurrDateCN("long"));}
}