Method close

xds/src/test/java/io/grpc/xds/StatefulFilter.java:51–57

()

  }

  @Override
  public void close() {
    if (!shutdown.compareAndSet(false, true)) {
      throw new ConcurrentModificationException(
          "Unexpected: StatefulFilter#close called multiple times");
    }
  }

  @Nullable
  @Override