vault: fix possible NPE if child iterator used after close

vault/VERSION

@@ -4,6 +4,6 @@
 # tags with and without build number so operators use the versioned
 # tag but we always keep a timestamped tag in case a semantic tag gets
 # replaced accidentally
-VER=1.0.5
+VER=1.0.6
 TAGS="${VER} ${VER}-$(date --utc +"%Y%m%dT%H%M%S")"
 unset VER

vault/build.gradle

@@ -36,7 +36,7 @@ dependencies {
     compile 'org.opencadc:cadc-gms:[1.0.5,)'
     compile 'org.opencadc:cadc-rest:[1.3.16,)'
     compile 'org.opencadc:cadc-vos:[2.0.6,)'
-    compile 'org.opencadc:cadc-vos-server:[2.0.14,)'
+    compile 'org.opencadc:cadc-vos-server:[2.0.15,)'
     compile 'org.opencadc:cadc-vosi:[1.3.2,)'
     compile 'org.opencadc:cadc-uws:[1.0,)'
     compile 'org.opencadc:cadc-uws-server:[1.2.19,)'

vault/src/main/java/org/opencadc/vault/NodePersistenceImpl.java

@@ -497,11 +497,17 @@ private class ChildNodeWrapper implements ResourceIterator<Node> {
 
         @Override
         public boolean hasNext() {
-            return childIter.hasNext();
+            if (childIter != null) {
+                return childIter.hasNext();
+            }
+            return false;
         }
 
         @Override
         public Node next() {
+            if (childIter == null) {
+                throw new NoSuchElementException("iterator closed");
+            }
             Node ret = childIter.next();
             ret.parent = parent;