Google API Tracing Token - Java

tracing_token_example.java

//// First, Implement an interface to intercept the HTTP Request before it goes out.
import java.io.IOException;
import com.google.api.client.googleapis.services.AbstractGoogleClientRequest;
import com.google.api.client.googleapis.services.GoogleClientRequestInitializer;

public class TracingTokenInitializer implements GoogleClientRequestInitializer {
  @Override
  public void initialize(AbstractGoogleClientRequest<?> req) throws IOException {
    System.out.println("Attaching tracing token...");
    req.put("trace", "token:<<TOKEN GOES HERE>>");
  }

}

// The interceptor must then be attached to Service builder objects before the 'build()' method is ran.
// Set the RequestInitailizer by utilizing the 'setGoogleClientRequestInitializer' method.
// The same initializer can be utilized for any Apiary-backed service (including: Drive, Directory, etc).
public static Reseller getResellerService(GoogleCredential credentials) {

  GoogleClientRequestInitializer tracingToken = new TracingTokenInitializer();
  Reseller service = new Reseller.Builder(HTTP_TRANSPORT, JSON_FACTORY, null)
  .setApplicationName(ApplicationName)
  .setHttpRequestInitializer(credentials)
  .setGoogleClientRequestInitializer(tracingToken).build();

  return service;
}

How do you receive the token parameter on the endpoint side?