code: public <K, V> Multimap<K, V> mul(String name, Class<K> ktype, Class<V> vtype) {
          Multimap<K, V> map = getNamedObject(name);
          if (map == null) putNamedObject(name, map = new Multimap<K, V>());
          return map;
      }
docs: Introduces a Multimap under the given name if one does not exist yet.