diff --git a/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractor.java b/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractor.java
index 0a1bfd1..603a554 100644
--- a/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractor.java
+++ b/src/main/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractor.java
@@ -129,8 +129,9 @@
       CommentAddedEvent event, Map<String, String> common) {
     common.putAll(propertyAttributeExtractor.extractFrom(event.author.get(), "commenter"));
     common.put("comment", event.comment);
-    if (event.approvals != null) {
-      for (ApprovalAttribute approvalAttribute : event.approvals.get()) {
+    ApprovalAttribute[] approvals = event.approvals.get();
+    if (approvals != null) {
+      for (ApprovalAttribute approvalAttribute : approvals) {
         common.putAll(propertyAttributeExtractor.extractFrom(approvalAttribute));
       }
     }
diff --git a/src/test/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractorTest.java b/src/test/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractorTest.java
index 33e8aa6..bfaa949 100644
--- a/src/test/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractorTest.java
+++ b/src/test/java/com/googlesource/gerrit/plugins/its/base/util/PropertyExtractorTest.java
@@ -211,6 +211,8 @@
         ImmutableMap.of("revision", "testRevision", "patchSetNumber", "3");
     expect(propertyAttributeExtractor.extractFrom(patchSetAttribute)).andReturn(patchSetProperties);
 
+    event.approvals = Suppliers.ofInstance(null);
+
     event.comment = "testComment";
     changeAttribute.project = "testProject";
     changeAttribute.number = 176;