import java.io.FileInputStream;
import java.io.IOException;
import java.util.List;
import com.google.openrtb.OpenRtb;
import com.google.openrtb.OpenRtb.BidRequest;
import com.google.openrtb.OpenRtb.BidResponse;
import com.google.openrtb.AdxExt;
import com.google.openrtb.AdxExt.ImpExt;
import com.google.protobuf.ExtensionRegistry;

public class OpenRTBExample {

  public static void main(String[] args) throws IOException {
    parseBidRequest();
  }

  public static void parseBidRequest() throws IOException {
    // Define the BidRequest extensions we intend to access.
    ExtensionRegistry registry = ExtensionRegistry.newInstance();
    registry.add(AdxExt.imp);

    // Parse the bid request.
    BidRequest bidRequest = BidRequest.parseFrom(
        new FileInputStream("examples/data/bid_request_openrtb.bin"), registry);

    System.out.printf("\tBidRequest.imp[0].ext.billing_id[0] = %d\n",
                      bidRequest.getImp(0).getExtension(AdxExt.imp).getBillingId(0));
  }
}