public interface State {
/**
+ * Returns the time when this state was retrieved.
+ *
+ * @return The time when this state was retrieved (in millseconds since Jan
+ * 1, 1970 UTC)
+ */
+ long time();
+
+ /**
* Whether the state was successfully retrieved. This method should only
* return {@code true} if a meaningful result could be retrieved; if e. g. a
* service is currently not reachable, this method should return false