Hi darch,

Each Adapter Set defined for an instance of Lightstreamer must necessarily have a Metadata Adapter defined in the adapters.xml.

We provide inside the ls-generic-adapters.jar a fake metadata, LiteralBasedProvider, which performs the basic functionality, such as the getItmes, which are always called from the server. You can see for example the HelloWorld demo and the adapters.xml configuration file proposed in this tutorial.

However, in realistic production scenarios, we recommend to implement a custom Metadata to implement authentication and security policies as well as the management of the ItemGroup and FieldSchema.

Please note that you can also implement a remote DataAdapter but a MetadataAdapter inprocess in Java with a minimal set of features implemented.

Hope that Helps.