解答：
public static void main(String[] args)throws ParseException {
//日期为 2020-03-21 15:23:31 输出结果为2020-03-22 8:23:31
// String dateStr = "2020-03-20 18:23:31";
//日期为2020-03-31 10:23:31 输出结果为2020-03-31 15:23:31
//String dateStr = "2020-03-31 10:23:31";
//日期为 2020-04-30 15:23:31 输出结果为2020-05-03 8:23:31
// String dateStr = "2020-04-30 15:23:31";
//日期为 2020-05-31 15:23:31 输出结果为2020-06-01 8:23:31
String dateStr ="2020-05-31 15:23:31";
String s =calculateWeekAndLy(dateStr);
System.out.println(s);
}
//计算 具体 截取的时间段
public static StringcountHourSecond(int monthTemp,int dayTemp,int hourTemp,String second,int week,int quantum){
//一周天数小于8
//j 用于区分星期6-7 分秒截取值（:00:00） k用于区分星期1-5 休息时间段上 分秒截取值为“:00:00"的情况
for (int i = week, j = -1,k = -1,n =0; i <8; i++) {
int[] monthOrDay =addMonthOrDay(monthTemp, dayTemp,hourTemp,i);
// 计算时间段< 4
int[] hourArr =timeQuantum(hourTemp, quantum,k);
if (monthOrDay[2] ==1) {
monthTemp = monthOrDay[0];
dayTemp = monthOrDay[1];
}
n = monthOrDay[2];
if (i <6) {
j =0;
if (hourArr[1] ==0) {
hourTemp = hourArr[0];
if (hourArr[2] ==0){
second =":00:00";
}
break;
}else if (hourArr[1] == -1) {
if (n ==0) {
dayTemp +=1;
}
hourTemp =8;
second =":00:00";
}
else {
if (n ==0) {
dayTemp +=1;
}
hourTemp =8 + hourArr[0];
k =1;
}
// 6 和7
}else {
if (n ==0) {
dayTemp +=1;
}
if (j == -1){
hourTemp =8;
second =":00:00";
}
if ( i ==7){
i =1;
}
}
}
String month = String.valueOf(monthTemp);
String day = String.valueOf(dayTemp);
if (month.length() ==1){
month ="0"+month;
}
if (day.length() ==1){
day ="0"+day;
}
return month+"-"+day+" "+hourTemp+second;
}
//计算 具体 截取的时间段
public static int[]timeQuantum(int hour,int quantum,int sign){
int rtn =0;
int mark =0;
// 星期5-7 已经取过值 得情况
if (sign != -1){
return new int[]{hour,mark,sign};
}
if (hour <8){
rtn =8+quantum;
sign =0;
}else if (hour <9){
rtn = hour + quantum;
}else if (hour <12){
rtn = hour + quantum +2;
}else if (hour <14){
// rtn = hour + quantum + (14-hour);
rtn =14 + quantum;
sign =0;
}else if (hour <15){
rtn = hour + quantum;
}else if (hour <18){
// 计算+1天
mark = -2;
if (hour !=15){
rtn = quantum -18 + hour;
}
}else {
// 晚于18 点 ，计算+1天
mark = -1;
sign =0;
}
return new int[]{rtn,mark,sign};
}
// 是否 增加 月份
public static int[]addMonthOrDay(int currentMonth, int day,int hourTemp,int week){
// 小月
int[] smlMonth = {4,6,9,11};
int finalCurrentMonth = currentMonth;
// SmallMonthBoolean
boolean SMB = Arrays.stream(smlMonth).anyMatch(f -> (f ==finalCurrentMonth));
// 18 - quantum
if (hourTemp <15 && (week !=6 || week !=7)){
return new int[]{0,0,0};
}
//是否润月 ，润年
if ((day ==29 || day ==28) && currentMonth ==2){
currentMonth +=1;
day =1;
return new int[]{currentMonth,day,1};
}
//小月
if (day ==30){
if (SMB){
currentMonth +=1;
day =1;
return new int[]{currentMonth,day,1};
}
}
//大月
if (day ==31){
currentMonth +=1;
day =1;
return new int[]{currentMonth,day,1};
}
// 为 null则正常表达
return new int[]{0,0,0};
}
//2020-03-21 14:23:31 计算所在日期 为星期几
public static StringcalculateWeekAndLy(String dateStr)throws ParseException {
int century = Integer.parseInt(dateStr.substring(0,2));
int year = Integer.parseInt(dateStr.substring(2,4));
int month = Integer.parseInt(dateStr.substring(5,7));
int day = Integer.parseInt(dateStr.substring(8,10));
// 星期几 计算公式 ：(y+[y/4]+[c/4]-2c+[26(m+1）/10]+d-1)%7
int week = (year+(year/4)+(century/4)-2*century+(26*(month+1)/10)+day-1)%7;
// 计算是否 闰年
// boolean leapYear = (century%400 == 0) || (century/4 == 0 && century%100 != 0);
int hour = Integer.parseInt(dateStr.substring(11,13));
String second = dateStr.substring(13);
String s =countHourSecond(month, day, hour, second, week +1,3);
return century+""+year+"-"+s;
}
思考：假如 是手动选择 几小时后的 工作时间点 怎么办？
