- * Gets the object. Since the object is cached, different calls to
- * this method may return different objects.
- *
+ * Gets the object. Since the object is cached, different calls to this
+ * method may return different objects.
+ *
+ * If the object is expired from the cache it is recomputed using the
+ * callback. In case the callback throws an exception the
+ * last known value is used. In case an exception is thrown, the problem is
+ * also logged. In case a recomputation is already being done by another
+ * thread, the last known value is immediately returned.
+ *