+ *
+ * <p>Implementations are expected to implement {@link #hashCode()} and {@link #equals(Object)} methods in a way,
+ * which ensures that objects before and after serialization are considered equal.
+ *
+ * <p>Implementations are advised to use the {@link java.io.Externalizable} Proxy pattern to allow future evolution
+ * of their serialization format. For further efficiency, implementations should consider implementing
+ * {@link WritableObject}, so they can be efficiently embedded in other {@link Serializable} and {@code WritableObject}s
+ * objects.