Merge remote-tracking branch 'origin/dev_v2.1.0' into dev_v2.1.0

teachcloud-report-business/src/main/java/com/qmth/teachcloud/report/business/service/impl/ReportCommonServiceImpl.java

@@ -239,7 +239,7 @@ public class ReportCommonServiceImpl implements ReportCommonService {
     public List<SurveyTeacherGradeDistributionResult> surveyTeacherDistribution(Long examId, String courseCode, Long collegeId) {
         List<SurveyTeacherDistributionResult> surveyTeacherDistributionResultList = taExamCourseRecordService.surveyTeacherDistribution(examId, courseCode);
         if (Objects.isNull(surveyTeacherDistributionResultList) || surveyTeacherDistributionResultList.size() == 0) {
-            return null;
+            return new ArrayList<>();
         }
         surveyTeacherDistributionResultList = surveyTeacherDistributionResultList.stream().filter(e -> !e.getAbsent()).collect(Collectors.toList());
         //过滤应届