Updating exception and explanation for update node leaves

Issue-ID: CPS-464 & CPS-465
Signed-off-by: niamhcore <niamh.core@est.tech>
Change-Id: I1880ceee66d89c49d039011163fa74bb7da19f25

2 files changed, 11 insertions, 2 deletions

diff --git a/cps-service/src/main/java/org/onap/cps/spi/model/DataNodeBuilder.java b/cps-service/src/main/java/org/onap/cps/spi/model/DataNodeBuilder.java
index 762e61ac59..4a9957deb4 100644
--- a/cps-service/src/main/java/org/onap/cps/spi/model/DataNodeBuilder.java
+++ b/cps-service/src/main/java/org/onap/cps/spi/model/DataNodeBuilder.java
@@ -29,6 +29,7 @@ import java.util.Map;
 import java.util.Set;
 import java.util.stream.Collectors;
 import lombok.extern.slf4j.Slf4j;
+import org.onap.cps.spi.exceptions.DataValidationException;
 import org.onap.cps.utils.YangUtils;
 import org.opendaylight.yangtools.yang.data.api.YangInstanceIdentifier;
 import org.opendaylight.yangtools.yang.data.api.schema.DataContainerChild;
@@ -142,6 +143,10 @@ public class DataNodeBuilder {
 
     private DataNode buildFromNormalizedNodeTree() {
         final Collection<DataNode> dataNodeCollection = buildCollectionFromNormalizedNodeTree();
+        if (!dataNodeCollection.iterator().hasNext()) {
+            throw new DataValidationException(
+                "Unsupported xpath: ", "Unsupported xpath as it is referring to one element");
+        }
         return dataNodeCollection.iterator().next();
     }
 
diff --git a/cps-service/src/main/java/org/onap/cps/utils/YangUtils.java b/cps-service/src/main/java/org/onap/cps/utils/YangUtils.java
index 0b66d37fba..b5c14a0721 100644
--- a/cps-service/src/main/java/org/onap/cps/utils/YangUtils.java
+++ b/cps-service/src/main/java/org/onap/cps/utils/YangUtils.java
@@ -94,9 +94,13 @@ public class YangUtils {
             final var jsonReader = new JsonReader(new StringReader(jsonData));
             jsonParserStream.parse(jsonReader);
 
-        } catch (final IOException | IllegalStateException | JsonSyntaxException exception) {
+        } catch (final IOException | JsonSyntaxException exception) {
             throw new DataValidationException(
-                    "Failed to parse json data: " + jsonData,  exception.getMessage(), exception);
+                "Failed to parse json data: " + jsonData, exception.getMessage(), exception);
+        } catch (final IllegalStateException illegalStateException) {
+            throw new DataValidationException(
+                "Failed to parse json data. Unsupported xpath or json data:" + jsonData, illegalStateException
+                .getMessage(), illegalStateException);
         }
         return normalizedNodeResult.getResult();
     }