Hi,

For general Write and Call service calls, see the SampleConsoleClient example methods SampleConsoleClient.write and SampleConsoleClient.callMethod and refer to javadocs for the SDK methods called.

Complex types are Structures and can be put into Variants the same way as basic types. Writing NodeSet2 files is outside of the scope of the SDK and can be done e.g. with tools like UaModeler. But once you have the model you can use the codegen that comes with the SDK to make the equivalent classes (see codegen manual for more information and the codegen/commandline/configexamples on how to generate some of the models we bundle, one of which is a SampleTypes model, which I recommend testing first).

Alternatively assuming you have connected to a server that has a custom Structure, you can use UaClient.getTypeDictionary().getStructureSpecification(…) to get a StructureSpecification object, then make a DynamicStructure object by passing that. That is a Structure that can be passed to Variants. For more information see the javadocs of the DynamicStructure.