extensions/servlet/src/com/google/inject/servlet/GuiceFilter.java
@Inject
  static void setPipeline(FilterPipeline pipeline) {

    // This can happen if you create many injectors and they all have their own
    // servlet module. This is legal, caveat a small warning.
    if (GuiceFilter.pipeline instanceof ManagedFilterPipeline) {
      LOGGER.warning(MULTIPLE_INJECTORS_WARNING);
    }

    // We overwrite the default pipeline
    GuiceFilter.pipeline = pipeline;
  }
@Inject
  static void setPipeline(FilterPipeline pipeline) {

    // This can happen if you create many injectors and they all have their own
    // servlet module. This is legal, caveat a small warning.
    if (GuiceFilter.pipeline instanceof ManagedFilterPipeline) {
      LOGGER.warning(MULTIPLE_INJECTORS_WARNING);
    }

    // We overwrite the default pipeline
    GuiceFilter.pipeline = pipeline;
  }
VisibleForTesting