。。

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

@@ -296,7 +296,7 @@ public class ExamServiceImpl implements ExamService {
 
 		examSettingsCache.remove(saved.getId());
 
-		if (null != properties.keySet()) {
+		if (null != properties) {
 			for (String cur : properties.keySet()) {
 				examPropertyCache.remove(saved.getId(), cur);
 			}