Added @Beta annotation to the flow objective API.

Change-Id: I4dd91921db1ff533b0ea1e3244dcdbf08b64a499
diff --git a/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultNextObjective.java b/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultNextObjective.java
index a034edb..956dbbe 100644
--- a/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultNextObjective.java
+++ b/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultNextObjective.java
@@ -15,6 +15,7 @@
  */
 package org.onosproject.net.flowobjective;
 
+import com.google.common.annotations.Beta;
 import com.google.common.collect.ImmutableList;
 import org.onosproject.core.ApplicationId;
 import org.onosproject.net.flow.TrafficTreatment;
@@ -29,6 +30,7 @@
 /**
  * Default implementation of a next objective.
  */
+@Beta
 public final class DefaultNextObjective implements NextObjective {
 
     private final List<TrafficTreatment> treatments;