I am new to Noda Time and I basically want to compare if a date has expired or not. In my case I have an object with the date it was created, represented by a LocalDate and the amount of months it's valid as an int, so I wanted to do a simple:
if ( Now > (dateCreated + validMonths) ) expired = true;
But I can't find in the Noda Time documentation the proper way to get the Now Date (they only show how to get the Now Time as SystemClock.Instance.Now) and the proper way to handle time comparisons.
For example if today is January 1st 2015 and the document was created in December 1st 2014, and it was valid for one month, today it expires its one month validity.
I miss methods such as isBefore() and isAfter() to compare dates and times. Simple overloads of the < > operators could also be very helpful.
EDIT:
1 - Sorry, there are < > operators to compare dates.
2 - I solve my problem using this code (not tested yet!):
...
LocalDate dateNow = this.clock.Now.InZone(DateTimeZoneProviders.Tzdb.GetSystemDefault()).LocalDateTime.Date;
LocalDate dateExpiration = DataASO.PlusMonths(validity);
return (dateNow < dateExpiration);
To get the current date, you need to specify which time zone you're in. So given a clock and a time zone, you'd use:
LocalDate today = clock.Now.InZone(zone).Date;
While you can use SystemClock.Instance, it's generally better to inject an IClock into your code, so you can test it easily.
Note that in Noda Time 2.0 this will be simpler, using ZonedClock, where it will just be:
LocalDate today = zonedClock.GetCurrentDate();
... but of course you'll need to create a ZonedClock by combining an IClock and a DateTimeZone. The fundamentals are still the same, it's just a bit more convenient if you're using the same zone in multiple places. For example:
// These are IClock extension methods...
ZonedClock zonedClock = SystemClock.Instance.InTzdbSystemDefaultZone();
// Or...
ZonedClock zonedClock = SystemClock.Instance.InZone(specificZone);
Related
With today's date, I should get the 16th date of next month.
For example, on passing 13-12-2021, I should get 16-01-2022.
I need to get the next month 16th day from current date (input date). Examples:
On passing 13-11-2021 should get 16-12-2021.
On passing 14-11-2021 should get 16-12-2021.
On passing 15-11-2021 should get 16-12-2021.
On passing 02-12-2021 should get 16-01-2022.
On passing 03-12-2021 should get 16-01-2022.
On passing 03-01-2022 should get 16-02-2022.
On passing 04-01-2022 should get 16-02-2022.
Any help will be much appreciated. Thanks.
java.time
One of the many strong points of java.time, the modern Java date and time API, is date arithmetic like this.
public static LocalDate nthDayOfFollowingMonth(
int desiredDayOfMonth, LocalDate currentDate) {
return YearMonth.from(currentDate)
.plusMonths(1)
.atDay(desiredDayOfMonth);
}
Try it out with your example date:
System.out.println(nthDayOfFollowingMonth(
16, LocalDate.of(2021, Month.DECEMBER, 13)));
Output:
2022-01-16
We might not have needed to convert to YearMonth and back to LocalDate. Doing so relieves both me and the reader of considering what happens if today’s day of month doesn’t exist in next month — for example if current date is 30 January (there is no 30 February). What one still wants to consider is what happens if you request a day of month tht doesn’t exist next month. For example on 13 January asking for the 30th of next month. We can try that out too:
System.out.println(nthDayOfFollowingMonth(
30, LocalDate.of(2022, Month.JANUARY, 13)));
I find the result very reasonable:
java.time.DateTimeException: Invalid date 'FEBRUARY 30'
In Mirth I receive a local datetime string (201801011000) which I need to convert to UTC. I soon found out using the classic js new Date() doesn't work well.
This for example:
var d = new Date("2018-01-01 10:00");
logger.info(d.toString());
gives me an Invalid Date.
So after some more searching I found I can do this:
var d = DateUtil.getDate("yyyyMMddHHmm", "201801011000");
and from here I'm stuck. I don't know how I can convert this to UTC. Local server timezone is assumed which is enough for now, but in the future I also need to set a specific non-local timezone.
I tried to get the methods I can use with Object.getOwnPropertyNames(d), but that gives me the helpfull TypeError: Expected argument of type object, but instead had type object
I also tried looking up the java docs for DateUtil and tried some methods from that, but nothing worked.
Does anybody know how I can convert datestring from local time to UTC? All tips are welcome!
Ok, after messing around with this for about two full days I finally found a solution. In the end I had to tap into Java, but since I couldn't import any java dependencies I had to use their direct class path (e.g.: java.text.SimpleDateFormat).
In the end this is what worked for me:
var datestr = "201207011000".slice(0, 12); // This is just a datetime string to test with
var formatter_hl7 = new java.text.SimpleDateFormat("yyyyMMddHHmm");
formatter_hl7.setTimeZone(java.util.TimeZone.getTimeZone("CET"));
var formatter_utc = new java.text.SimpleDateFormat("yyyy-MM-dd HH:mm");
formatter_utc.setTimeZone(java.util.TimeZone.getTimeZone("UTC"));
var date_in_utc = formatter_utc.format(formatter_hl7.parse(date_str));
Regardless, I wish you all a beautiful day!
tl;dr
Do not use DateUtil whatever that is. (Perhaps Apache DateUtils library?)
Do not use terrible old date-time classes such as java.util.Date.
Use the modern industry-leading java.time classes.
Code for parsing a string lacking an offset, then assigning an offset of zero for UTC itself.
LocalDateTime // Represents a date and a time-of-day but without any concept of time zone or offset-from-UTC. NOT a moment, NOT a point on the timeline.
.parse(
"201801011000" ,
DateTimeFormatter.ofPattern( "uuuuMMddHHmm" )
)
.atOffset( ZoneOffset.UTC ) // Assign an offset-from-UTC. Do this only if you are CERTAIN this offset was originally intended for this input but was unfortunately omitted from the text. Returns an `OffsetDateTime`.
.toInstant() // Extract an `Instant` from the `OffsetDateTime`. Basically the same thing. But `Instant` is always in UTC by definition, so this type is more appropriate if your intention is to work only in UTC. On the other hand, `Instant` is a basic class, and `OffsetDateTime` is more flexible such as various formatting patterns when generating `String` object to represent its value.
Using java.time
The modern approach in Java uses the java.time classes. This industry-leading framework supplanted the terribly troublesome old date-time classes such as Date, Calendar, and SimpleDateFormat.
DateTimeFormatter
Parse your input string. Define a formatting pattern to match.
DateTimeFormatter f = DateTimeFormatter.ofPattern( "uuuuMMddHHmm" ) ;
String input = "201801011000" ;
LocalDateTime
Parse as a LocalDateTime because your input lacks an indicator for time zone or offset-from-UTC.
LocalDateTime ldt = LocalDateTime.parse( input , f ) ;
Lacking a zone or offset means this does not represent a moment, is not a point on the timeline. Instead, this represents potential moments along a range of about 26-27 hours, the range of time zones around the globe.
OffsetDateTime
If you know for certain that this date and time-of-day were intended to represent a moment in UTC, apply the constant ZoneOffset.UTC to get an OffsetDateTime object.
OffsetDateTime odt = ldt.atOffset( ZoneOffset.UTC ) ;
ZonedDateTime
Your Question is vague. It sounds like you might know of an specific time zone intended for this input. If so, assign a ZoneId to get a ZonedDateTime object.
Understand that an offset-from-UTC is but a mere number of hours, minutes, and seconds. Nothing more, nothing less. In contrast, a time zone is much more. A time zone is a history of past, present, and future changes to the offset used by the people of a certain region.
Specify a proper time zone name in the format of continent/region, such as America/Montreal, Africa/Casablanca, or Pacific/Auckland. Never use the 3-4 letter abbreviation such as EST or IST as they are not true time zones, not standardized, and not even unique(!).
ZoneId z = ZoneId.of( "Africa/Tunis" ) ;
ZonedDateTime zdt = ldt.atZone( z ) ;
Instant
A quick way to adjust back into UTC is to extract a Instant object. An Instant is always in UTC.
Instant instan = zdt.toInstant() ;
ISO 8601
Tip: Instead of using custom format for exchanging date-time values as text, use only the standard ISO 8601 formats. The standard formats are practical, easy to parse by machine, easy to read by humans across cultures.
The java.time classes use the ISO 8601 formats by default when parsing/generating strings. The ZonedDateTime::toString method wisely extends the standard to append the name of the zone in square brackets.
Instant instant = Instant.parse( "2018-07-23T16:18:54Z" ) ; // `Z` on the end means UTC, pronounced “Zulu”.
String output = instant.toString() ; // 2018-07-23T16:18:54Z
And always include the offset and time zone in your string. Omitting the offset/zone for a moment is like omitting the currency for a price: All you have left is an ambiguous number worth nothing. Actually, worse than nothing as it can cause all sorts of confusion and errors.
About java.time
The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.
The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.
To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.
You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.
Where to obtain the java.time classes?
Java SE 8, Java SE 9, Java SE 10, and later
Built-in.
Part of the standard Java API with a bundled implementation.
Java 9 adds some minor features and fixes.
Java SE 6 and Java SE 7
Much of the java.time functionality is back-ported to Java 6 & 7 in ThreeTen-Backport.
Android
Later versions of Android bundle implementations of the java.time classes.
For earlier Android (<26), the ThreeTenABP project adapts ThreeTen-Backport (mentioned above). See How to use ThreeTenABP….
The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.
In my project have function for convert datestring local time to UTC,
function getDateInUTC(dateString) {
return new java.text.SimpleDateFormat("yyyy-MM-dd HH:mm").setTimeZone(java.util.TimeZone.getTimeZone("UTC")).format(new java.text.SimpleDateFormat("yyyyMMddHHmm").setTimeZone(java.util.TimeZone.getTimeZone("CET")).parse(dateString));
}
Enjoy :)
You should use the latest classes java.time provided from Java8.
Steps are as follows:
Step-1. Parse String to LocalDateTime
Step-2. Convert LocalDateTime to the ZonedDateTime and then we can convert between different timezone.
Hope this help:
In Mirth you can write as:
String str = "201207011000";
var date_in_utc =java.time.format.DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm")
.format(java.time.ZonedDateTime.of(java.time.LocalDateTime
.parse(str,java.time.format.DateTimeFormatter
.ofPattern("yyyyMMddHHmm")),java.time.ZoneId.of("CET"))
.withZoneSameInstant(java.time.ZoneOffset.UTC));
Full Snippet:
ZoneId cet = ZoneId.of("CET");
String str = "201207011000";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("yyyyMMddHHmm");
LocalDateTime localtDateAndTime = LocalDateTime.parse(str, formatter);
ZonedDateTime dateAndTimeInCET = ZonedDateTime.of(localtDateAndTime, cet );
System.out.println("Current date and time in a CET timezone : " + dateAndTimeInCET);
ZonedDateTime utcDate = dateAndTimeInCET.withZoneSameInstant(ZoneOffset.UTC);
System.out.println("Current date and time in UTC : " + utcDate);
System.out.println("Current date and time in UTC : " + DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm").format(utcDate));
Give this a shout
var d = DateUtil.getDate("yyyyMMddHHmm", "201801011000");
var utcD = new Date(d).toISOString();
edit: Info on .toISOString() https://developer.mozilla.org/en-US/docs/Web/JavaScript/Reference/Global_Objects/Date/toISOString
I'm currently working with embarcadero c++, this is the first time I'm working with it so it's completely new to me.
What I'm trying to achieve is to get the current date, make sure the date has the "dd/MM/yyyy" format. When I'm sure this is the case I want to add a month to the current date.
So let's say the current date is 08/18/2016 this has to be changed to 18/08/2016 and then the end result should be 18/09/2016.
I've found that there is a method for this in embarcardero however I'm not sure how to use this.
currently I've only been able to get the current date like this.
TDateTime currentDate = Date();
I hope someone will be able to help me out here.
I figured it out.
After I've searched some more I found the way to use the IncMonth method on this page.
The example given my problem is as follows:
void __fastcall TForm1::edtMonthsExit(TObject *Sender)
{
TDateTime StartDate = edtStartDate->Text;
int Months = edtMonths->Text.ToInt();
TDateTime NextPeriod = IncMonth(StartDate, Months);
edtNextPeriod->Text = NextPeriod;
}
After looking at I changed my code accordingly to this
TDateTime CurrentDate = Date();
TDateTime EndDate = IncMonth(CurrentDate, 1);
A date object doesn't have a format like "dd/MM/yyyy". A date object is internally simply represented as a number (or possibly some other form of representation that really isn't your problem or responsibility).
So you don't have to check if it's in this format because no date objects will ever be in this format, they simply don't have a format.
You will have to do additions/subtractions on the Date object that the language or library gives you, THEN (optionally) you can format it to a human-readable string so it looks like 18/08/2016 or 18th of August 2016 or whatever other readable format that you choose.
It might be that the TRANSFER of a date between 2 systems is in a similar format, but then formatting the date like that is entirely up to you.
As for how to do that, the link you posted seems like a possible way (or alternatively http://docwiki.embarcadero.com/Libraries/Berlin/en/System.SysUtils.IncMonth), I'm afraid I can't give you an example as I'm not familiar with the tool/language involved, I'm just speaking generically about Date manipulations and they should ALWAYS be on the raw object.
With DateJS, you'd add e.g. six months to the current date like this:
Date.today().addMonths(6);
However, I need to add 24 months not to today's date, but to a date which a user has typed into a date field. So the today() should in principle be replaced by something like this.getField('begin_date').value.
The result shall be written into another data form field.
I tried hard, but couldn't make it. Can anyone help me out?
Providing the input value is a textual representation of a date, you need to convert it into a Date object at the first place. Then you can work with it as you want.
DateJS has a pretty smart parse() function which does exactly that, so you'd achieve it like this:
Date.parse(this.getField('begin_date').value).addMonths(24)
When a specific date format is needed, like DD.MM.YYYY commonly used in Europe, you can use parseExact() and specify the format. Like this:
Date.parseExact(dateToParse, 'dd.MM.yyyy') // leading zeroes required; parses 01.04.2014 but not 1.4.2014
Date.parseExact(dateToParse, 'd.M.yyyy') // leading zeroes not required; parses both 01.04.2014 and 1.4.2014
Here is a solution that I found for my problem, using DateJS as well:
start = this.getField('begin_date').value;
var d1 = util.scand("dd.mm.yyyy", start);
var myDate = new Date(d1);
result = myDate.addMonths(24);
This works pretty fine, also spanning leap years, except for the 28th of February, 2014/2018/2022 ... ; the result then will be the 28th of February, 2016/2020/2024 ... and not the 29th of February 2016/2020/2024... In these cases it's up to the user to accept the 28th or to manually change the date to the 29th.
I would like to calculate precisely the months between two dates to achieve this I do something like :
DateTimeZone ZONE = DateTimeZone.forID("Europe/London");
String DATE_FORMAT = "dd/MM/yyyy";
DateTimeFormatter FORMATTER = DateTimeFormat.forPattern(DATE_FORMAT).withZone(ZONE);
LocalDate dateTime = FORMATTER.parseLocalDate("28/05/2013");
LocalDate dateTime6MonthAfter = FORMATTER.parseLocalDate("28/02/2014");
Period todayUntilEndOfContract = new Period(dateTime,dateTime6MonthAfter);
todayUntilEndOfContract.getMonths() +"M/"+ todayUntilEndOfContract.getWeeks() +"W/"+ todayUntilEndOfContract.getDays() +"D/");
So this give me precisely 9 month between 28/05/2013 and 28/02/2014 BUT!!!
when I calculate the dates (29, 30, 31)/05/2013 with 28/02/2014 it always give me 9 month normally it should say 8M/3W/(6,5,4)D/ why is it always 9M/0W/0D please...?
Thanks a lot
Your issue is that you are expecting something a little different than what is provided. If I ask you the question "what is 30th January plus one month?" then there are a number of different answers which are valid under different assumptions. In Joda's case the answer is "28th February" (or 29th if a leap year).
Although you are asking for month-based information I would suggest that you obtain the number of days instead and use that as a basis, as it is probably closer to what you need:
int days = Days.daysBetween(dateTime, dateTime6MonthAfter).getDays();
You can always use this number to feed back in to your code and obtain different values to fit your requirements.