docs: @SuppressWarnings("unchecked")
      public <T> Set<T> getContextSet(String key) {
          Set<T> set = (Set<T>) attributes.get(key);
          if (set == null) {
              set = new HashSet<T>();
              attributes.put(key, set);
  
              if (TraceComponent.isAnyTracingEnabled() && tc.isDebugEnabled()) {
                  Tr.debug(tc, "ConfigContext create set instance for {0}", key);
              }
          }
          return set;
      }