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Checking dates if it is in a range

My Java FX app handles hours worked. I have work start and end time in 2 date fields. I succeeded in calculating the differences between 2 datesTime; but now how could I check if the result is in a night or day range???? The day begin at 6 and ends at 22h. For example someone who worked between 3Am till 11Pm.
Here is below how I did to have the total number of hours worked.
public void CalculNbreJourTravaille() {
SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyy HH:mm");
try {
Date ddtt = format.parse(ddt.getText());
Date dftt = format.parse(dft.getText());
long diff = dftt.getTime() - ddtt.getTime();
long diffhours = diff / (60*60*1000)%24;
long diffdays = diff/(24*60*60*1000);
long total = diffhours + (diffdays*24);
result.setText(total + " Hours");
} catch (ParseException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
We have workers who can work beyond 10PM, and the pay would not be the same. If they work after 10pm, they will have a special pay. We pay at the end of the work. They could would work only 10 days or more.

You should use the new DateTimeFormatter class to give you a LocalDateTime object, which you can pull the hour from.
DateTimeFormatter format = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm");
LocalDateTime localDateTimeFrom = format.parse(dateFrom.getText(), LocalDateTime::from);
LocalDateTime localDateTimeTo = format.parse(dateTo.getText(), LocalDateTime::from);
int hoursFrom = localDateTimeFrom.getHour();
int hoursTo = localDateTimeTo.getHour();
boolean workedNight = hoursFrom < 6 || hoursTo > 22;

Here’s my attempt to cover all of your requirements. I wrote the code before reading that you don’t require that summer time (DST) is taken into account, so I am using ZonedDateTime to get correct hours also across summer time transitions. For the same reason I need to iterate over each day. For each date I calculate the hours worked at night time and the hours worked at day time.
If you want to make sure that summer time is not taken into account, use LocalDateTime instead of ZonedDateTime. In this case there may also be a possible performance gain in calculating the whole work days in one lump rather than one day at a time.
The code below uses 28/03/2018 03:00 and 29/03/2018 23:30 as example start and end time. Expected total hours worked are 44.5 since one day is 24 hours and there are 20.5 hours from 03:00 to 23:30. The expected day time hours are 32 since there are 16 daytime hours each of the two days. This leaves 12.5 hours as night time. And indeed the code prints
Day 32.0 hours; night 12.5 hours
The program follows. Please fill in the correct time zone where I put America/Monterey.
static ZoneId zone = ZoneId.of("America/Monterrey");
static LocalTime dayStart = LocalTime.of(6, 0);
static LocalTime dayEnd = LocalTime.of(22, 0);
static DateTimeFormatter formatter = DateTimeFormatter.ofPattern("d/M/uuuu H:mm");
public static void main(String[] args) {
String workStartString = "28/03/2018 03:00";
String workEndString = "29/03/2018 23:30";
calculateWorkingHours(workStartString, workEndString);
}
public static void calculateWorkingHours(String workStartString, String workEndString) {
ZonedDateTime workStart
= LocalDateTime.parse(workStartString, formatter).atZone(zone);
ZonedDateTime workEnd
= LocalDateTime.parse(workEndString, formatter).atZone(zone);
if (workEnd.isBefore(workStart)) {
throw new IllegalArgumentException("Work end must not be before work start");
}
LocalDate workStartDate = workStart.toLocalDate();
LocalDate workEndDate = workEnd.toLocalDate();
Duration workedDaytime = Duration.ZERO;
// first calculate work at nighttime before the start date, that is, work before 06:00
Duration workedNighttime
= calculateNightTime(workStartDate.minusDays(1), workStart, workEnd);
for (LocalDate d = workStartDate; ! d.isAfter(workEndDate); d = d.plusDays(1)) {
workedDaytime = workedDaytime.plus(calculateDayTime(d, workStart, workEnd));
workedNighttime = workedNighttime.plus(calculateNightTime(d, workStart, workEnd));
}
double dayHours = workedDaytime.toMinutes() / (double) TimeUnit.HOURS.toMinutes(1);
double nightHours = workedNighttime.toMinutes() / (double) TimeUnit.HOURS.toMinutes(1);
System.out.println("Day " + dayHours + " hours; night " + nightHours + " hours");
}
/**
* Calculates amount of work in daytime on d,
* that is between 06:00 and 22:00 on d.
* Only time that falls with in workStart to workAnd
* and also falls within 06:00 to 22:00 on d is included.
*
* #param d The date for which to calculate day work
* #param workStart
* #param workEnd
* #return Amount of daytime work on the said day
*/
private static Duration calculateDayTime(LocalDate d, ZonedDateTime workStart, ZonedDateTime workEnd) {
ZonedDateTime dayStartToday = d.atTime(dayStart).atZone(zone);
ZonedDateTime dayEndToday = d.atTime(dayEnd).atZone(zone);
if (workStart.isAfter(dayEndToday) || workEnd.isBefore(dayStartToday)) {
return Duration.ZERO;
}
// restrict calculation to daytime on d
if (workStart.isBefore(dayStartToday)) {
workStart = dayStartToday;
}
if (workEnd.isAfter(dayEndToday)) {
workEnd = dayEndToday;
}
return Duration.between(workStart, workEnd);
}
/**
* Calculates amount of night work in the night after d,
* that is from 22:00 on d until 06:00 the next morning.
*
* #param d The date for which to calculate night work
* #param workStart
* #param workEnd
* #return Amount of nighttime work in said night
*/
private static Duration calculateNightTime(LocalDate d, ZonedDateTime workStart, ZonedDateTime workEnd) {
assert ! workEnd.isBefore(workStart);
ZonedDateTime nightStart = d.atTime(dayEnd).atZone(zone);
ZonedDateTime nightEnd = d.plusDays(1).atTime(dayStart).atZone(zone);
if (workEnd.isBefore(nightStart) || workStart.isAfter(nightEnd)) {
return Duration.ZERO;
}
// restrict calculation to the night after d
if (workStart.isBefore(nightStart)) {
workStart = nightStart;
}
if (workEnd.isAfter(nightEnd)) {
workEnd = nightEnd;
}
return Duration.between(workStart, workEnd);
}

You can check the LocalTime part of a LocalDateTime to have a simple check using isAfter and isBefore.
I will use those values for this example.
LocalDateTime start = LocalDateTime.of(2018, Month.APRIL, 30, 23, 0);
LocalDateTime end = LocalDateTime.of(2018, Month.MAY, 1, 5, 0);
Then define the limit for the night.
LocalTime startNight = LocalTime.of(22, 0);
LocalTime endNight = LocalTime.of(6, 0);
And simply use get the LocalTime of both date and check if they are in the range. You can get the value using toLocalTime.
if(start.toLocalTime().isAfter(startNight) &&
end.toLocalTime().isBefore(endNight)){
System.out.println("NIGHT TIME");
} else {
System.out.println("DAY TIME");
}
NIGHT TIME
The output is valid since we start at 23:00 and end at 05:00.
Using this allow a simpler solution if you need to define a time like LocalTime.of(5,45) for 5:45
This is an example, this might need some adaptation if it is allowed to start part 22 but keep working after 6. This is just an example on how to use those methods.

This is easier, if you use the java.time API. You simply need to check, if the dates differ or if the starting time not in the range from 6:00 to 22:00:
private static final LocalTime START_TIME = LocalTime.of(6, 0); // 06:00
private static final LocalTime END_TIME = LocalTime.of(22, 0); // 22:00
private static final DateTimeFormatter FORMATTER = DateTimeFormatter.ofPattern("dd/MM/yyyy HH:mm");
// parse from input strings
LocalDateTime start = LocalDateTime.parse(startText, FORMATTER);
LocalDateTime end = LocalDateTime.parse(endText, FORMATTER);
boolean nightTime =
!start.toLocalDate().equals(end.toLocalDate())
|| start.toLocalTime().isBefore(START_TIME)
|| end.toLocalTime().isAfter(END_TIME);
// todo: change output to gui
System.out.println("night time: " + nightTime);
System.out.println("duration : " + Duration.between(start, end).toHours());

Define two formatters. One Fromatter to get date with time from edittext. And other On to get 12AM of that day. Now we need Date Objects corresponding to 6AM and 11PM of the same day. We can get those by adding that much milliseconds to the 12AM Object. These added dates can be used for comparison.
SimpleDateFormat df_zero_hours = new SimpleDateFormat("dd/MM/yyy");
SimpleDateFormat format = new SimpleDateFormat("dd/MM/yyyy HH:mm");
Date ddtt = format.parse(ddt.getText()); //Work Start Time
Date dftt = format.parse(dft.getText()); //Work End Time
Date dateStart = df_zero_hours.parse(ddt.getText()); //12AM of the day job started
Date dayStart = new Date();
dayStart.setTime(dateStart.getTime()+6*60*60*1000); // Get 6AM of that day
Date dayEnd = new Date();
dayEnd.setTime(dateStart.getTime()+22*60*60*1000); //Get 10PM of that day
// Now check the worked hours. in Whatever way you need
boolean isBefore6AM = (dayStart.getTime()-ddtt.getTime())>0;
boolean isAfter10PM = (dftt.getTime()-dayEnd.getTime())>0;

Java Subtract 2 duration in HH:MM:SS

I have 2 string in java (HH:MM:SS) please take note this is not time, but duration, i used end time - start time to get these values:
Case1:
duration1 = "12:04:45";
duration2 = "13:04:45";
Expected result: duration1 - duration 2 = "-1:00:00" (Note that there is negative)
Case2:
duration1 = "15:13:32";
duration2 = "12:04:45";
Expected result: duration1 - duration 2 = "3:08:47"
How can i do that? My attempt for the Case1 (codes modified from Java add dates of format dd:HH:mm:ss):
SimpleDateFormat format = new SimpleDateFormat("HH:mm:ss");
String s1 = "12:04:45";
String s2 = "13:04:45";
Date d1 = format.parse(s1);
Date d2 = format.parse(s2);
int sec = d1.getSeconds() - d2.getSeconds();
int min = d1.getMinutes() - d2.getMinutes();
int hr = d1.getHours() - d2.getHours();
Time sum = new Time(hr, min, sec);
System.out.println(sum); // Output: 23:00:00 which is wrong

Using LocalTime or date calculations like some people suggest doesn't work if your period involved more than 24 hours since that doesn't fit in a day.
If you don't have Java 8, you can use JodaTime. I've just checked that this code also works with JodaTime 1.6.2, which is the last version that still works with JDK 1.4.2.
PeriodFormatter formatter = new PeriodFormatterBuilder()
.printZeroAlways().minimumPrintedDigits(2)
.appendHours().appendSuffix(":").appendMinutes().appendSuffix(":").appendSeconds()
.toFormatter();
Period period1 = formatter.parsePeriod("12:04:45");
Period period2 = formatter.parsePeriod("13:04:45");
Period difference1 = period1.minus(period2).normalizedStandard();
System.out.println(formatter.print(difference1));
Period period3 = formatter.parsePeriod("15:13:32");
Period period4 = formatter.parsePeriod("12:04:45");
Period difference2 = period3.minus(period4).normalizedStandard();
System.out.println(formatter.print(difference2));
Output:
-01:00:00
03:08:47
JodaTime:
Version 1.6.2 source: https://github.com/JodaOrg/joda-time/releases/tag/v1.6.2
Version 1.6.2 Maven Jar artifact: http://mvnrepository.com/artifact/joda-time/joda-time/1.6.2

With the Java time API you could use a Duration to calculate the duration and format it as you want:
String s1 = "12:04:45";
String s2 = "13:04:45";
LocalTime t1 = LocalTime.parse(s1);
LocalTime t2 = LocalTime.parse(s2);
Duration d = Duration.between(t2, t1);
System.out.println(d); //PT-1H
If you want to print it as -1:00:00 you will need to tweak the output format. It could look like this:
private static String toHHMMSS(Duration d) {
long hours = d.toHours();
int minutes = (int) (d.toMinutes() % 60);
int secs = (int) (d.getSeconds() % 60);
return hours + ":" + minutes + ":" + secs;
}

Use Calendar to calculate the time difference.
You can query each field and/or format as a time string as this example shows:
private Calendar getTimeDiffDate(Date d1, Date d2) {
Calendar c = Calendar.getInstance();
c.setTime(new Date(d1.getTime()-d2.getTime()));
SimpleDateFormat formatter = new SimpleDateFormat("HH:mm:ss");
// Format as a time string:
String formattedTime = formatter.format(c.getTime());
System.out.println("formattedTime: "+formattedTime);
// Query by each field:
System.out.println("Hours: "+c.get(Calendar.HOUR));
System.out.println("Minutes: "+c.get(Calendar.MINUTE));
System.out.println("Seconds: "+c.get(Calendar.SECOND));
return c;
}

Add hours and Minutes to a certain time java

I have String initialTime= "10:30:00"
I am converting it into time like so:-
DateFormat sdf = new SimpleDateFormat("hh:mm:ss");
Date date = sdf.parse(initialTime);
Time time = new Time(date.getTime());
int initHour = time.getHours()
int initMind = time.getMinutes();
Further I have two values;
int hour, mins;
The hour value can be anything from 0-10;
mins value can be 0,15,30,45.
The user selects a time by selecting hour and mins. As soon as the user selects the values they should get added to the initialTimeand shown in finalTIme
So if:-
hour=0 and mins=15 then finalTIme=10:45:00
hour=0 and mins=35 then finalTIme=11:00:00
hour=0 and mins=45 then finalTIme=11:15:00
I tried doing something like:-
if(hour==0 && mins==0)
{
finalTime = initialTime;
}
else if(hour==0 && mins>0 && mins <30)
{
mins = initMins + mins
}
else if(hour==0 && mins>0 && mins >=30)
{
hours = hours+1;
mins = mins-60;
}
But I did not get the required output. HOw can I do it in a less complicated manner?

You can use java.util.Calendar class:
DateFormat sdf = new SimpleDateFormat("hh:mm:ss");
Date date = sdf.parse(initialTime);
Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.add(Calendar.HOUR_OF_DAY, hours);
cal.add(Calendar.MINUTE, minutes);
date = cal.getTime();
You might also consider the new Date API from JDK 8.

convert string to seconds

how can i convert string time to seconds if my hour time is greater than 24hours. My time comes from a table column
Ex:
Column Name (Late): Time (String): 00:40:00
Conversion:
new SimpleDateFormat("hh:mm:ss").parse($F{late}).getHours()*3600
+ new SimpleDateFormat("hh:mm:ss").parse($F{late}).getMinutes()*60
+ new SimpleDateFormat("hh:mm:ss").parse($F{late}).getSeconds();
OutPut: 2400
The above result is perfect but if my field value results: 31:58:00, Then my above expression is not working.
The output is : 28680
28680 is a remainder of (115080-86400)
but the actually output should be '115080'.

I suggest you should convert it to time of the day (i.e. 31:58:00 - 24:00:00) then calculate both and sum-up.

What you have to remember is there are only 24 hours in day, so your example value is actually 1d, 7 hours and 58 minutes.
Now, you could simply break the String down and apply simple mathamtics to calculate the time values...
seconds = (hours * 60 * 60) + (minutes * 60) + seconds;
But, where's the fun in that. Another approach would be to use a zero based Calendar, for example...
String time = "31:58:00";
Calendar cal = Calendar.getInstance(TimeZone.getTimeZone("GMT"));
cal.setTimeInMillis(0);
String[] parts = time.split(":");
cal.set(Calendar.HOUR_OF_DAY, Integer.parseInt(parts[0]));
cal.set(Calendar.MINUTE, Integer.parseInt(parts[1]));
cal.set(Calendar.SECOND, Integer.parseInt(parts[2]));
long millis = cal.getTimeInMillis();
long seconds = millis / 1000;
System.out.println(seconds);
Which essentially does the same thing but makes use of Calendar's auto rolling feature.
There's probably even a really neat trick which could be used with JodaTime
Updated with JodaTime example
PeriodFormatter pf = new PeriodFormatterBuilder().
appendHours().appendSeparator(":").
appendMinutes().appendSeparator(":").
appendSeconds().toFormatter();
Period period = pf.parsePeriod("31:58:00");
System.out.println(period.toStandardSeconds().getSeconds());

Thanks to All, Here is the java code what i have return
import java.text.DateFormat;
import java.text.ParseException;
import java.text.SimpleDateFormat;
import java.util.concurrent.TimeUnit;
public class TestDate {
public static void main(String[] args) throws ParseException {
String timee="31:58:55";
DateFormat format=new SimpleDateFormat("hh:mm:ss");
// format.parse(timee).getSeconds();
int seconds = format.parse(timee).getHours()*3600+format.parse(timee).getMinutes()*60+format.parse(timee).getSeconds();
String[] parts = timee.split(":");
long millis = TimeUnit.HOURS.toSeconds(Long.parseLong(parts[0]))
+ TimeUnit.MINUTES.toSeconds(Long.parseLong(parts[1])) + Long.parseLong(parts[2]);
System.out.println(millis+" in Seconds");
//System.out.println(seconds + " Converted to Seconds");
long s_hour = TimeUnit.SECONDS.toHours(millis);
long tempSec = millis - (TimeUnit.HOURS.toSeconds(s_hour));
long s_minute = TimeUnit.SECONDS.toMinutes(tempSec) ;
long tempSec1 = tempSec - (TimeUnit.MINUTES.toSeconds(s_minute));
long s_seconds = TimeUnit.SECONDS.toSeconds(tempSec);
System.out.println(s_hour + " in Hours");
System.out.println(tempSec+" Which is a reminder");
System.out.println(s_minute + " in Minutes");
System.out.println(tempSec1+" in Seconds");
}
}

how to parse this date

I cant quite figure out what the format should be to parse this date. Its a millisecond value followed by timezone. thx.
// so far tried: "S Z"
// "SSSSSSSSSSS-ZZZZ",
// "SSSSSSSSSSS-Z",
// etc.
Format formatter = new SimpleDateFormat("SSSSSSSSSSSS Z", Locale.CANADA);
// source string looks like this /Date(928164000000-0400)/
String temp = jsonUserObj.getString("DateOfBirth").substring(6, 6+17);
System.err.println("got date="+temp);
Date date = (Date) formatter.parseObject(temp);

You can do it without parser.
String[] parts = new String[]{temp.substring(0, temp.indexOf('-')), temp.substring(temp.indexOf('-') + 1)};
long millis = Long.parseLong(parts[0]);
parts[1] = parts[1].replaceAll("^0*(\\-?[0-9]*)$", "$1");
int timeZone = Integer.parseInt(parts[1]);
int rawOffset = (timeZone / 100) * 3600000 + (timeZone % 100);
GregorianCalendar cal = new GregorianCalendar();
cal.setTimeInMillis(millis);
cal.setTimeZone(new SimpleTimeZone(rawOffset, "GMT"));

SimpleDateFormat expects a milliseconds value < 1000, as it expects you would increment seconds, then minutes, etc, for larger values.
You'll need to convert the value first; this post might help: Unix epoch time to Java Date object