Hello,

I would need some more information on your Methods.

When you say “multiple devices, where the same method is contained”, do you mean literally the same Method as in the exact same Method Node or two separate instances of the Method Node?

You’re saying that “nodeId = uaMethod = Device_01:SwitchOn() = Device_02:SwitchOn()” but I’m not exactly sure what you mean with this. Does this mean that the Method Nodes have the same NodeId, which would mean that they’re actually the same Node, or something else?

Hello,

Since the Nodes have the same NodeId, they are both the same Node. In OPC UA it is allowed for different instances of an ObjectType to Reference a shared Method Node instead of creating unique Method Nodes. This is also how the SDK creates instances of ObjectTypes by default.

As onGetUserExecutable identifies the Method Node based on its NodeId, it is impossible for it to provide different values for UserExecutable Attribute based on the “parent” Node of the SwitchOn Method Node.

Therefore you have two options:

The first option is to set the UserExecutable to true for the Method Node and have the onCall method of CallableListener check the objectId and have the Method call fail depending on which Object the Method was called for. This can also be done when using the static implementation of the Method as the generated interface will have the Node the Method was called for as one of its parameters.

The problem with this approach is that it doesn’t provide Clients the information on whether or not they can execute the Method.

The second option is to create TypeDefinitionBasedNodeBuilderConfiguration with MethodInstantiationLogic set to UNIQUE. You can do this using the following code:

where nodeManagerUaNode is an instance of a class that extends NodeManagerUaNode. This should be done before creating the instances of MyDeviceType with nodeManagerUaNode and it will make it so that unique Method Nodes are created for all instances of MyDeviceType (and any other ObjectTypes that have Methods). The SwitchOn Method Nodes will now have unique NodeIds, which allows you to configure onGetUserExecutable to provide different values for them.

If you are expecting to create only few instances of MyDeviceType then there should be no problem using this option. But if you need to create thousands of instances of MyDeviceType, then you might have to consider how much memory is required for all the unique instances of SwitchOn Method as opposed to one shared instance.