public static <B> MutableClassToInstanceMap<B> create(Map<Class<? extends B>, B> backingMap) {
    return new MutableClassToInstanceMap<B>(backingMap);
  }
public static <B> MutableClassToInstanceMap<B> create(Map<Class<? extends B>, B> backingMap) {
    return new MutableClassToInstanceMap<B>(backingMap);
  }
public static < B > MutableClassToInstanceMap < B > create ( Map < Class < ? extends B > , B > backingMap ) { return new MutableClassToInstanceMap < B > ( backingMap ) ; }
Returns a new {@code MutableClassToInstanceMap} instance backed by a given empty {@code
backingMap}. The caller surrenders control of the backing map, and thus should not allow any
direct references to it to remain accessible.
Returns a new {