Fix isViable test

Change-Id: Iba04aa1ae84ea737ff64a9f62edd60158df51b59
diff --git a/utils/misc/src/main/java/org/onlab/graph/ScalarWeight.java b/utils/misc/src/main/java/org/onlab/graph/ScalarWeight.java
index ccf0c2a..f82bb3a 100644
--- a/utils/misc/src/main/java/org/onlab/graph/ScalarWeight.java
+++ b/utils/misc/src/main/java/org/onlab/graph/ScalarWeight.java
@@ -58,7 +58,7 @@
 
     @Override
     public boolean isViable() {
-        return this != NON_VIABLE_WEIGHT;
+        return !this.equals(NON_VIABLE_WEIGHT);
     }
 
     @Override
diff --git a/utils/misc/src/test/java/org/onlab/graph/TestDoubleWeight.java b/utils/misc/src/test/java/org/onlab/graph/TestDoubleWeight.java
index 54f9f17..d0fa7fc 100644
--- a/utils/misc/src/test/java/org/onlab/graph/TestDoubleWeight.java
+++ b/utils/misc/src/test/java/org/onlab/graph/TestDoubleWeight.java
@@ -59,7 +59,7 @@
 
     @Override
     public boolean isViable() {
-        return this != NON_VIABLE_WEIGHT;
+        return !this.equals(NON_VIABLE_WEIGHT);
     }
 
     @Override