relax conditions of "is this energy value" logic (#1731)

Author: goekay

src/main/java/de/rwth/idsg/steve/utils/TransactionStopServiceHelper.java

@@ -51,29 +51,32 @@ public static boolean isEnergyValue(TransactionDetails.MeterValues v) {
             return false;
         }
 
-        // from 1.6 docs: "To retain backward compatibility, the default values of all of the optional fields on a
-        // sampledValue element are such that a value without any additional fields will be interpreted, as a register
-        // reading of active import energy in Wh (Watt-hour) units."
-        if (Strings.isNullOrEmpty(v.getReadingContext())
-            && Strings.isNullOrEmpty(v.getFormat())
-            && Strings.isNullOrEmpty(v.getMeasurand())
-            && Strings.isNullOrEmpty(v.getLocation())
-            && Strings.isNullOrEmpty(v.getUnit())
-            && Strings.isNullOrEmpty(v.getPhase())) {
-            return true;
-        }
+        //
+        // init relevant fields with default values if empty
+        //
+        ValueFormat format = Strings.isNullOrEmpty(v.getFormat())
+            ? ValueFormat.RAW
+            : ValueFormat.fromValue(v.getFormat());
+
+        Measurand measurand = Strings.isNullOrEmpty(v.getMeasurand())
+            ? Measurand.ENERGY_ACTIVE_IMPORT_REGISTER
+            : Measurand.fromValue(v.getMeasurand());
+
+        UnitOfMeasure unit = Strings.isNullOrEmpty(v.getUnit())
+            ? UnitOfMeasure.WH
+            : UnitOfMeasure.fromValue(v.getUnit());
 
         // if the format is "SignedData", we cannot make any sense of this entry. we don't know how to decode it.
         // https://github.com/steve-community/steve/issues/816
-        if (ValueFormat.SIGNED_DATA.value().equals(v.getFormat())) {
+        if (ValueFormat.SIGNED_DATA == format) {
             return false;
         }
 
-        if (!isWHOrKWH(v.getUnit())) {
+        if (!isWHOrKWH(unit)) {
             return false;
         }
 
-        if (!Measurand.ENERGY_ACTIVE_IMPORT_REGISTER.value().equals(v.getMeasurand())) {
+        if (Measurand.ENERGY_ACTIVE_IMPORT_REGISTER != measurand) {
             return false;
         }
 
@@ -84,7 +87,7 @@ public static boolean isEnergyValue(TransactionDetails.MeterValues v) {
         return true;
     }
 
-    private static boolean isWHOrKWH(String str) {
-        return UnitOfMeasure.WH.value().equals(str) || UnitOfMeasure.K_WH.value().equals(str);
+    private static boolean isWHOrKWH(UnitOfMeasure unit) {
+        return UnitOfMeasure.WH == unit || UnitOfMeasure.K_WH == unit;
     }
 }