src/main/java/com/seanchenxi/gwt/storage/client/StorageKeyFactory.java
public static <T extends Serializable> StorageKey<T> serializableKey(String keyName){
      return new StorageKey<>(keyName, Serializable.class);
  }
public static <T extends Serializable> StorageKey<T> serializableKey(String keyName){
      return new StorageKey<>(keyName, Serializable.class);
  }
Returns Serializable type value's storage key.

@param keyName name of storage key
@param <T> type of value
@return Serializable type value's storage key