Override toString for flow objectives

Change-Id: I725ca9ac231e21c12f364e1a8bbdc6d3cd1e5a38
diff --git a/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultForwardingObjective.java b/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultForwardingObjective.java
index 7c442b2..fd08fd4 100644
--- a/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultForwardingObjective.java
+++ b/core/api/src/main/java/org/onosproject/net/flowobjective/DefaultForwardingObjective.java
@@ -24,6 +24,7 @@
 import java.util.Objects;
 import java.util.Optional;
 
+import static com.google.common.base.MoreObjects.toStringHelper;
 import static com.google.common.base.Preconditions.checkArgument;
 import static com.google.common.base.Preconditions.checkNotNull;
 
@@ -146,6 +147,23 @@
         return false;
     }
 
+    @Override
+    public String toString() {
+        return toStringHelper(this)
+                .add("id", id())
+                .add("op", op())
+                .add("priority", priority())
+                .add("selector", selector())
+                .add("treatment", treatment())
+                .add("nextId", nextId())
+                .add("flag", flag())
+                .add("appId", appId())
+                .add("permanent", permanent())
+                .add("timeout", timeout())
+                .add("context", context())
+                .toString();
+    }
+
     /**
      * Returns a new builder.
      *