。。。。

examcloud-core-examwork-service/src/main/java/cn/com/qmth/examcloud/core/examwork/service/impl/ExamServiceImpl.java

@@ -296,8 +296,10 @@ public class ExamServiceImpl implements ExamService {
 
 		examSettingsCache.remove(saved.getId());
 
-		for (String cur : properties.keySet()) {
-			examPropertyCache.remove(saved.getId(), cur);
+		if (null != properties.keySet()) {
+			for (String cur : properties.keySet()) {
+				examPropertyCache.remove(saved.getId(), cur);
+			}
 		}
 
 		return saved;