code: public <T> void setState(HttpConnectionInterceptor interceptor, String stateName, T
              stateObjectToStore) {
          Map<String, Object> state = interceptorStates.get(interceptor);
          if (state == null) {
              interceptorStates.put(interceptor, (state = new ConcurrentHashMap<String, Object>()));
          }
          state.put(stateName, stateObjectToStore);
      }
docs: Store some state on this request context associated with the specified interceptor instance.
  Used where a single interceptor instance needs to associate state with each HTTP request.
  
  @param interceptor        the interceptor instance
  @param stateName          the key to store the state object under
  @param stateObjectToStore the state object to store
  @param <T>                the type of the state object to store
  @see #getState(HttpConnectionInterceptor, String, Class)
  @since 2.6.0