update

mec-biz/src/main/java/com/ym/mec/biz/service/impl/ImUserFriendServiceImpl.java

@@ -141,6 +141,9 @@ public class ImUserFriendServiceImpl extends BaseServiceImpl<Long, ImUserFriend>
 		//获取班级关联的学员列表
 		Set<Integer> studentIds = classGroupStudentMapperDao.queryStudentIdsByClassGroupId(courseSchedule.getClassGroupId(),null,null);
 		ClassGroup classGroup = classGroupDao.get(courseSchedule.getClassGroupId());
+		if(classGroup == null){
+			return;
+		}
 		GroupType groupType = classGroup.getGroupType();
 		List<ImUserFriend> imUserFriends = saveImUserFriends(studentIds, teacherIds, groupType, classGroup.getMusicGroupId());
 		if(imUserFriends.size() > 0){