minor fix in DocumentPath, DCS

Change-Id: I13f332bc3897e7fc047744c36be4f208cf820d4f
diff --git a/apps/config/src/main/java/org/onosproject/config/impl/DistributedDynamicConfigStore.java b/apps/config/src/main/java/org/onosproject/config/impl/DistributedDynamicConfigStore.java
index 48b370d..7c73922 100644
--- a/apps/config/src/main/java/org/onosproject/config/impl/DistributedDynamicConfigStore.java
+++ b/apps/config/src/main/java/org/onosproject/config/impl/DistributedDynamicConfigStore.java
@@ -125,19 +125,18 @@
     @Override
     public CompletableFuture<Boolean>
     addNode(ResourceId complete, DataNode node) {
-        CompletableFuture<Boolean> eventFuture = CompletableFuture.completedFuture(true);
         String spath = ResourceIdParser.parseResId(complete);
         if (spath == null) {
             throw new FailedException("Invalid RsourceId, cannot create Node");
         }
-        if (spath.compareTo(ResourceIdParser.ROOT) != 0) {
+        if (!spath.equals(ResourceIdParser.ROOT)) {
             if (completeVersioned(keystore.get(DocumentPath.from(spath))) == null) {
                 throw new FailedException("Node or parent does not exist for " + spath);
             }
         }
         spath = ResourceIdParser.appendNodeKey(spath, node.key());
         parseNode(spath, node);
-        return eventFuture;
+        return CompletableFuture.completedFuture(true);
     }
 
     private void parseNode(String path, DataNode node) {
diff --git a/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java b/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
index 333cbb1..0ef9aef 100644
--- a/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
+++ b/core/api/src/main/java/org/onosproject/store/service/DocumentPath.java
@@ -74,8 +74,8 @@
     public DocumentPath(String nodeName, DocumentPath parentPath) {
         checkNotNull(nodeName, "Node name cannot be null");
         if (nodeName.contains(pathSeparator)) {
-            throw new IllegalDocumentNameException(
-                    "Periods are not allowed in names.");
+            throw new IllegalDocumentNameException("'" + pathSeparator + "'" +
+                    " are not allowed in names.");
         }
         if (parentPath != null) {
             pathElements.addAll(parentPath.pathElements());