ON PROTOBUFS This maven module has core protobuf definition files ('.protos') used by hbase REST that ship with hbase core including tests. The protobuf version they use can be distinct from that used by HBase internally since HBase started shading its protobuf references. REST Endpoints have no access to the shaded protobuf hbase uses. They do have access to the content of hbase-protocol -- the .protos found in here -- but avoid using as much of this as you can as it is liable to change. Generation of java files from protobuf .proto files included here is done as part of the build.