How to check if an item exists?

[Dries]

Hi,

I’m trying to keep my rules rather generic.
This means that I don’t always refer to item by their direct name. E.g. something like

"sendCommand(KNX_GV_Keuken_Sonos_10_1_0, ON)"

But sometimes the item name is composed out of some other variables. An example:

val itemName = gAllecontacten.allMembers.filter[sw|sw.name.contains(in_UDPmsg.substring(1, 5))].head
    postUpdate(itemName, in_UDPmsg.substring(5))

If I created my items correctly, this should not be a problem. But I just want to have a check if there really is an item meeting the conditions defined in “itemName”.
If the itemname exists => proceed with the code.
If the itemname does not exist => loginfo + execute alternative code.

So how do I check if e.g. item abcd really exists in my OpenHAB setup?

[rossko57]

@Dries

So how do I check if e.g. item abcd really exists in my OpenHAB setup?

You could put them in a group, and search the group for item name

You might find this contains relevant ideas

Design Pattern: Associated Items

Please see Design Pattern: What is a Design Pattern and How Do I Use Them for how to read and use DPs. Problem Statement Often one will have a number of separate Items which are all related to each other in some way. For example, one might have a Contact on a door and a DateTime to represent when the last time the door was opened. This is easy enough to keep track of if there are only one or two such Items, but if one has a lot of similar Items or is using a lot of generically coded rules where…

[Dries]

Thanks!
I assumed there was an “if exist item” option (I had this in another programming language).

val RelatedWindowContact = gRaamcontact.allMembers.filter[sw|sw.name.contains("something here")].head
		if (RelatedWindowContact == null) {
				// some logic
		} else {
				// some other logic	
		}