fix:获取分部学年制的年级列表报错

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

@@ -91,6 +91,10 @@ public class OrganizationServiceImpl extends BaseServiceImpl<Integer, Organizati
 		Organization organization = organizationDao.get(id);
 		Map<Integer, String> gradeMap = new HashMap<>();
 
+		if(Objects.isNull(organization)){
+			return gradeMap;
+		}
+
 		if(organization.getGradeType().equals(GradeTypeEnum.FIVE_PLUS)){
 			FivePlusGradeEnum[] fivePlusGradeEnums = FivePlusGradeEnum.values();
 			for (FivePlusGradeEnum fivePlusGradeEnum : fivePlusGradeEnums) {