code: public void write(String packageName, String implClassName, PrintWriter printWriter,
        GinjectorBindings rootBindings) throws UnableToCompleteException {
      writeInjectorHierarchy(rootBindings);
  
      TypeLiteral<?> ginjectorInterface = rootBindings.getGinjectorInterface();
      if (ginjectorInterface != null) {
        writeInterface(ginjectorInterface, packageName, implClassName, printWriter, rootBindings);
      }
    }
docs: Writes the implementation of the {@link Ginjector} interface associated
  with the given {@link GinjectorBindings} object, if any, along with all the
  injector classes and fragment classes required by the implementation.