ONOS-5214:Fix-For-Meter-WrongBandType-with-NPE-And-WrongUNITType-Issue


Change-Id: Ia7a56644ad55c458ef17f31b2cf7ec9b9210dd06
(cherry picked from commit 726839c57f8a5df62c5d28ec205f128f417ffef7)
diff --git a/core/common/src/main/java/org/onosproject/codec/impl/MeterRequestCodec.java b/core/common/src/main/java/org/onosproject/codec/impl/MeterRequestCodec.java
index a92e96e..b64fd23 100644
--- a/core/common/src/main/java/org/onosproject/codec/impl/MeterRequestCodec.java
+++ b/core/common/src/main/java/org/onosproject/codec/impl/MeterRequestCodec.java
@@ -74,7 +74,7 @@
 
         // parse unit type
         String unit = nullIsIllegal(json.get(UNIT), UNIT + MISSING_MEMBER_MESSAGE).asText();
-        Meter.Unit meterUnit;
+        Meter.Unit meterUnit = null;
 
         switch (unit) {
             case "KB_PER_SEC":
@@ -84,8 +84,7 @@
                 meterUnit = Meter.Unit.PKTS_PER_SEC;
                 break;
             default:
-                log.warn("The requested unit {} is not defined for meter.", unit);
-                return null;
+                nullIsIllegal(meterUnit, "The requested unit " + unit + " is not defined for meter.");
         }
 
         // parse meter bands