DateTime Conversion (openHAB 3.x)

#2

val zdt = Instant.ofEpochMilli(XXX).atZone(ZoneId.systemDefault())
val MyDateTimeType = new DateTimeType(zdt)
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hey there

I’m having trouble to figure out the right syntax in OH3 for this:

if (now.isAfter((Sunset_Time.state as DateTimeType).zonedDateTime.toInstant.toEpochMilli) || now.isBefore((Sunrise_Time.state as DateTimeType).zonedDateTime.toInstant.toEpochMilli)

Any hint? thank you very much

Sorry for asking, but I don’t get any further allthough reading this over and ober again…
Can somebody give me a code example how to store the time (now) in a variable, and then later calculate the difference in seconds to that stored value??
Thanks,
Ingo

2 Likes

Something like this (?):
Post current time to item
My_Item.postUpdate(new DateTimeType())

Get Epoch from Item:
val Number item_millis = (My_Item.state as DateTimeType).zonedDateTime.toInstant.toEpochMilli

Get Now Epoch:
val Number now_millis = now.toInstant.toEpochMilli

Difference in Minutes:
var Number diff = (now_millis - item_millis)/60000

3 Likes

@dakoeli: This works for my setup very well! This is exactly what I needed in order to sum up my “uptime firing unit” for calculation of my energy consumption!

Thank you very much!

Thanks a lot!!!

I still don’t get it to work. I have made a TestRule which I trigger by Hand:

//val DateTimeType Epoche = now.toInstant()
val DateTimeType Epoche = now.toInstant()
logInfo("TestTrigger", "Epoche 2: " + Epoche)


createTimer(now.plusSeconds(3 )) [|
    val DateTimeType Spaeter = now.toInstant()
logInfo("TestTrigger", "Spaeter 4: " + Spaeter)
    val DateTimeType Differenz = Duration.between (Spaeter, Epoche)
logInfo("TestTrigger", "Differenz 5: " + Differenz)

// Here I need to convert from "DateTimeType" to a kind of Number. I want the time Difference in Millisecond or seconds......
	]

This is working so far. I can calculate timedifferences between 2 given times. I get as result:

Differenz 5: PT-3.003164S

which is fine. Now I need this as Number, e.g. “3000” .
So how can the DateTimeType be converted to a Number???

Thanks again,
Ingo

I would try the following

val Number millis_spaeter = Spaeter.getZonedDateTime.toInstant.toEpochMilli
val Number millis_epoche = Epoche.getZonedDateTime.toInstant.toEpochMilli

For rule internal internal calculations I would recommend to stay with the Java 11 classes like “ZonedDateTime” or “LocalDateTime”. The DateTimeType I would only use if I want to populate an Openhab Item with it.

(from the javadoc DateTimeType (openHAB Core 3.1.0-SNAPSHOT API))

@ljsquare You are right, thanks. I looked up the code of DateTimeType , and it turns out it’s only a thin wrapper around ZonedDateTime. So there is an easy conversion between the two, without the need for any String parsing or formatting.

I’ve rewritten my rule as follows:

  val morning_start = ZonedDateTime.now().with(LocalTime.MIDNIGHT).plusHours(7) // 7:00

  // Java time to DateTimeType:
  vMorning_Time.postUpdate(new DateTimeType(morning_start)) 

  // DateTimeType to Java time:
  val day_start = (vSunrise_Time.state as DateTimeType).getZonedDateTime()

Much cleaner and less error prone.

@anfaenger May I suggest to rewrite section #3 of your start post, as follows?

#3 Get DateTimeType from Java Time

DateTimeType has a conventient constructor method that accepts Java java.time.LocalDateTime objects. So getting a DateTimeType if you have a java.time.LocalDateTime is as easy as:

val LocalDateTime myLocalDateTime = new LocalDateTime();
val DateTimeType myDateTimeType = new DateTimeType(myLocalDateTime);
4 Likes

Sorry for “hijacking” that chat, but I do not come any further.
My Rules for measuring “working times per day” don’t work under OH3 any more. (And I spent a Day now not getting them to work)
I have A switch which can be On or Off. I need to store the time when the switch goes high, and when it went back to low again. Then subtrated it and transfered the result to an Integer (Seconds).
Seconds = MakeSeconds(TimeNow - TimeBefore)

Maybe you can tell me how to do that OH3 conform?
Thanks in advance,
Ingo

@bartkummel Thank you for this hint!
I was not yet familiar with the LocalDateTime class.
Can you have a look at my rewrite? I hope I didn’t mess things up.
I’m still on openHAB 2.4 with my system and therefor can’t test it.

Variant B can be rewritten as follows:

val DateTimeType myDateTimeTypeFromJavaTime = new DateTimeType(myJavaTime.toLocalDateTime())

The “timestamp” variant can be removed, it is not different from “variant B”.

I use a DateTime Item and switched to the MainUI website and configuration. For me it is not clear how to format the DateTime Code in the UI like this
DD.MM.YY, HH:MM
Is there some Metadata config needed or do I have to format it in the UI?

Have you tried #12?

Ok, then I always have to use a second Item?
With the textual configuration I had the chance to directly format DateTime and illustrate it at the sitemap. Is that still possible?

Do you mean item like this?

DateTime MyDateTimeItem       "Date[%1$tA %1$td.%1$tm.%1$tY   %1$tH:%1$tM]" 

Yes, exactly. I do not know how to do that in the UI.
I guess maybe with Metadata?

I am just realizing that I have probably misunderstood.
You are probably switching from textual confiuration to another option.
Unfortunately, I can not help.

@bartkummel Thanks! I’m working on it.