最近在写日历，发现很多开源的常用的日历根本不能显示出除夕这个节日，所以在github上找到一个计算出大部分农历之后修改了一下，这里科普下，除夕有可能是29，也有可能是30，中国农历一个月只有29天或者20天。
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.Date;
import java.util.Locale;
/**
* Created by wxj on 2018/1/31.
*/
public class LunarCalendar {
private int year; // 农历的年份
private int month;
private int day;
private String lunarMonth; // 农历的月份
public int leapMonth = 0; // 闰的是哪个月
final static String chineseNumber[] = { "一", "二", "三", "四", "五", "六", "七", "八", "九", "十", "十一", "十二" };
static SimpleDateFormat chineseDateFormat = new SimpleDateFormat("yyyy年MM月dd日", Locale.CHINA);
final static long[] lunarInfo = new long[] { //
0x04bd8, 0x04ae0, 0x0a570, 0x054d5, 0x0d260, 0x0d950, 0x16554, 0x056a0, 0x09ad0, //
0x055d2, 0x04ae0, 0x0a5b6, 0x0a4d0, 0x0d250, 0x1d255, 0x0b540, 0x0d6a0, 0x0ada2, //
0x095b0, 0x14977, 0x04970, 0x0a4b0, 0x0b4b5, 0x06a50, 0x06d40, 0x1ab54, 0x02b60, //
0x09570, 0x052f2, 0x04970, 0x06566, 0x0d4a0, 0x0ea50, 0x06e95, 0x05ad0, 0x02b60, //
0x186e3, 0x092e0, 0x1c8d7, 0x0c950, 0x0d4a0, 0x1d8a6, 0x0b550, 0x056a0, 0x1a5b4, //
0x025d0, 0x092d0, 0x0d2b2, 0x0a950, 0x0b557, 0x06ca0, 0x0b550, 0x15355, 0x04da0, //
0x0a5d0, 0x14573, 0x052d0, 0x0a9a8, 0x0e950, 0x06aa0, 0x0aea6, 0x0ab50, 0x04b60, //
0x0aae4, 0x0a570, 0x05260, 0x0f263, 0x0d950, 0x05b57, 0x056a0, 0x096d0, 0x04dd5, //
0x04ad0, 0x0a4d0, 0x0d4d4, 0x0d250, 0x0d558, 0x0b540, 0x0b5a0, 0x195a6, 0x095b0, //
0x049b0, 0x0a974, 0x0a4b0, 0x0b27a, 0x06a50, 0x06d40, 0x0af46, 0x0ab60, 0x09570, //
0x04af5, 0x04970, 0x064b0, 0x074a3, 0x0ea50, 0x06b58, 0x055c0, 0x0ab60, 0x096d5, //
0x092e0, 0x0c960, 0x0d954, 0x0d4a0, 0x0da50, 0x07552, 0x056a0, 0x0abb7, 0x025d0, //
0x092d0, 0x0cab5, 0x0a950, 0x0b4a0, 0x0baa4, 0x0ad50, 0x055d9, 0x04ba0, 0x0a5b0, //
0x15176, 0x052b0, 0x0a930, 0x07954, 0x06aa0, 0x0ad50, 0x05b52, 0x04b60, 0x0a6e6, //
0x0a4e0, 0x0d260, 0x0ea65, 0x0d530, 0x05aa0, 0x076a3, 0x096d0, 0x04bd7, 0x04ad0, //
0x0a4d0, 0x1d0b6, 0x0d250, 0x0d520, 0x0dd45, 0x0b5a0, 0x056d0, 0x055b2, 0x049b0, //
0x0a577, 0x0a4b0, 0x0aa50, 0x1b255, 0x06d20, 0x0ada0 };
// 农历部分假日
final static String[] lunarHoliday = new String[] { "0101 春节", "0115 元宵", "0505 端午", "0707 情人", "0715 中元", "0815 中秋", "0909 重阳", "1208 腊八", "1224 小年", "0100 除夕" };
// 公历部分节假日
final static String[] solarHoliday = new String[] { //
"0101 元旦", "0214 情人", "0308 妇女", "0312 植树", "0315 消费者权益日", "0401 愚人", "0501 劳动", "0504 青年", //
"0512 护士", "0601 儿童", "0701 建党", "0801 建军", "0808 父亲", "0909 毛泽东逝世纪念", "0910 教师", "0928 孔子诞辰",//
"1001 国庆", "1006 老人", "1024 联合国日", "1112 孙中山诞辰纪念", "1220 澳门回归纪念", "1225 圣诞", "1226 毛泽东诞辰纪念" };
// ====== 传回农历 y年的总天数
final private static int yearDays(int y) {
int i, sum = 348;
for (i = 0x8000; i > 0x8; i >>= 1) {
if ((lunarInfo[y - 1900] & i) != 0)
sum += 1;
}
return (sum + leapDays(y));
}
// ====== 传回农历 y年闰月的天数
final private static int leapDays(int y) {
if (leapMonth(y) != 0) {
if ((lunarInfo[y - 1900] & 0x10000) != 0)
return 30;
else
return 29;
} else
return 0;
}
// ====== 传回农历 y年闰哪个月 1-12 , 没闰传回 0
final private static int leapMonth(int y) {
int result = (int) (lunarInfo[y - 1900] & 0xf);
return result;
}
// ====== 传回农历 y年m月的总天数
final private static int monthDays(int y, int m) {
if ((lunarInfo[y - 1900] & (0x10000 >> m)) == 0)
return 29;
else
return 30;
}
// ====== 传回农历 y年的生肖
final public String animalsYear(int year) {
final String[] Animals = new String[] { "鼠", "牛", "虎", "兔", "龙", "蛇", "马", "羊", "猴", "鸡", "狗", "猪" };
return Animals[(year - 4) % 12];
}
// ====== 传入 月日的offset 传回干支, 0=甲子
final private static String cyclicalm(int num) {
final String[] Gan = new String[] { "甲", "乙", "丙", "丁", "戊", "己", "庚", "辛", "壬", "癸" };
final String[] Zhi = new String[] { "子", "丑", "寅", "卯", "辰", "巳", "午", "未", "申", "酉", "戌", "亥" };
return (Gan[num % 10] + Zhi[num % 12]);
}
// ====== 传入 offset 传回干支, 0=甲子
final public String cyclical(int year) {
int num = year - 1900 + 36;
return (cyclicalm(num));
}
public static String getChinaDayString(int day) {
String chineseTen[] = { "初", "十", "廿", "卅" };
int n = day % 10 == 0 ? 9 : day % 10 - 1;
if (day > 30)
return "";
if (day == 10)
return "初十";
else
return chineseTen[day / 10] + chineseNumber[n];
}
/**
* 传出y年m月d日对应的农历. yearCyl3:农历年与1864的相差数 ? monCyl4:从1900年1月31日以来,闰月数
* dayCyl5:与1900年1月31日相差的天数,再加40 ?
*
* isday: 这个参数为false---日期为节假日时，阴历日期就返回节假日 ，true---不管日期是否为节假日依然返回这天对应的阴历日期
*
* @return
*/
public String getLunarDate(int year_log, int month_log, int day_log,
boolean isday) {
// @SuppressWarnings("unused")
int yearCyl, monCyl, dayCyl;
// int leapMonth = 0;
String nowadays;
Date baseDate = null;
Date nowaday = null;
try {
baseDate = chineseDateFormat.parse("1900年1月31日");
} catch (ParseException e) {
e.printStackTrace(); // To change body of catch statement use
// Options | File Templates.
}
nowadays = year_log + "年" + month_log + "月" + day_log + "日";
try {
nowaday = chineseDateFormat.parse(nowadays);
} catch (ParseException e) {
e.printStackTrace(); // To change body of catch statement use
// Options | File Templates.
}
// 求出和1900年1月31日相差的天数
int offset = (int) ((nowaday.getTime() - baseDate.getTime()) / 86400000L);
dayCyl = offset + 40;
monCyl = 14;
// 用offset减去每农历年的天数
// 计算当天是农历第几天
// i最终结果是农历的年份
// offset是当年的第几天
int iYear, daysOfYear = 0;
for (iYear = 1900; iYear < 10000 && offset > 0; iYear++) {
daysOfYear = yearDays(iYear);
offset -= daysOfYear;
monCyl += 12;
}
if (offset < 0) {
offset += daysOfYear;
iYear--;
monCyl -= 12;
}
// 农历年份
year = iYear;
setYear(year); // 设置公历对应的农历年份
yearCyl = iYear - 1864;
leapMonth = leapMonth(iYear); // 闰哪个月,1-12
boolean leap = false;
// 用当年的天数offset,逐个减去每月（农历）的天数，求出当天是本月的第几天
int iMonth, daysOfMonth = 0;
for (iMonth = 1; iMonth < 13 && offset > 0; iMonth++) {
// 闰月
if (leapMonth > 0 && iMonth == (leapMonth + 1) && !leap) {
--iMonth;
leap = true;
daysOfMonth = leapDays(year);
} else
daysOfMonth = monthDays(year, iMonth);
offset -= daysOfMonth;
// 解除闰月
if (leap && iMonth == (leapMonth + 1))
leap = false;
if (!leap)
monCyl++;
}
// offset为0时，并且刚才计算的月份是闰月，要校正
if (offset == 0 && leapMonth > 0 && iMonth == leapMonth + 1) {
if (leap) {
leap = false;
} else {
leap = true;
--iMonth;
--monCyl;
}
}
// offset小于0时，也要校正
if (offset < 0) {
offset += daysOfMonth;
--iMonth;
--monCyl;
}
month = iMonth;
setLunarMonth(chineseNumber[month - 1] + "月"); // 设置对应的阴历月份
day = offset + 1;
if (!isday) {
// 如果日期为节假日则阴历日期则返回节假日
// setLeapMonth(leapMonth);
for (int i = 0; i < solarHoliday.length; i++) {
// 返回公历节假日名称
String sd = solarHoliday[i].split(" ")[0]; // 节假日的日期
String sdv = solarHoliday[i].split(" ")[1]; // 节假日的名称
String smonth_v = month_log + "";
String sday_v = day_log + "";
String smd = "";
if (month_log < 10) {
smonth_v = "0" + month_log;
}
if (day_log < 10) {
sday_v = "0" + day_log;
}
smd = smonth_v + sday_v;
if (sd.trim().equals(smd.trim())) {
return sdv;
}
}
for (int i = 0; i < lunarHoliday.length; i++) {
// 返回农历节假日名称
String ld = lunarHoliday[i].split(" ")[0]; // 节假日的日期
String ldv = lunarHoliday[i].split(" ")[1]; // 节假日的名称
String lmonth_v = month + "";
String lday_v = day + "";
String lmd = "";
if (month < 10) {
lmonth_v = "0" + month;
}
if (day < 10) {
lday_v = "0" + day;
}
lmd = lmonth_v + lday_v;
if ("12".equals(lmonth_v)) { // 除夕夜需要特殊处理
if ((daysOfMonth == 29 && day == 29) || (daysOfMonth == 30 && day == 30)) {
return ldv;
}
}
if (ld.trim().equals(lmd.trim())) {
return ldv;
}
}
}
if (day == 1)
return chineseNumber[month - 1] + "月";
else
return getChinaDayString(day);
}
public String toString() {
if (chineseNumber[month - 1] == "一" && getChinaDayString(day) == "初一")
return "农历" + year + "年";
else if (getChinaDayString(day) == "初一")
return chineseNumber[month - 1] + "月";
else
return getChinaDayString(day);
// return year + "年" + (leap ? "闰" : "") + chineseNumber[month - 1] +
// "月" + getChinaDayString(day);
}
/*
* public static void main(String[] args) { System.out.println(new
* LunarCalendar().getLunarDate(2012, 1, 23)); }
*/
public int getLeapMonth() {
return leapMonth;
}
public void setLeapMonth(int leapMonth) {
this.leapMonth = leapMonth;
}
/**
* 得到当前日期对应的阴历月份
*
* @return
*/
public String getLunarMonth() {
return lunarMonth;
}
public void setLunarMonth(String lunarMonth) {
this.lunarMonth = lunarMonth;
}
/**
* 得到当前年对应的农历年份
*
* @return
*/
public int getYear() {
return year;
}
public void setYear(int year) {
this.year = year;
}
} 这个类写的很通俗，如果你要计算某一天是农历几月初几，直接使用方法getLunarDate即可。
最后添加一个链接，里面是很多个android开源的日历效果图，满足产品经理的要求。