I have multiple modules and I am confused about why most of the modules generated from myspec.asn by the OSS ASN.1/Java compiler are empty.

The reason for the generation of empty Java classes is that with the OSS ASN.1/Java compiler the last module is considered the root module. Whichever type you want to be the PDU should be defined in the last module.

For more information, see the descriptions of the -root command line option and the OSS.ROOT directive.

The samples included with some of the Knowledge Center answers are meant for your general understanding of the OSS products. Different versions of the products might produce slightly different outputs. Consult the products documentation and samples for the most up-to-date products information and code examples.