submit:讲义修改

zhongzheng-system/src/main/java/com/zhongzheng/modules/course/service/impl/CourseHandoutsServiceImpl.java

@@ -4,6 +4,7 @@ import cn.hutool.core.bean.BeanUtil;
 import cn.hutool.core.lang.Validator;
 
 import com.baomidou.mybatisplus.core.conditions.query.LambdaQueryWrapper;
+import com.baomidou.mybatisplus.core.toolkit.ObjectUtils;
 import com.baomidou.mybatisplus.core.toolkit.Wrappers;
 import com.baomidou.mybatisplus.extension.service.impl.ServiceImpl;
 import com.github.pagehelper.Page;
@@ -84,7 +85,7 @@ public class CourseHandoutsServiceImpl extends ServiceImpl<CourseHandoutsMapper,
             });
             courseHandoutsVo.setFileList(courseFileVos);
         } else {
-            List<CourseFileVo> fileVos = courseFileVos.stream().filter(item -> item.getParentId() == 0L).collect(Collectors.toList());
+            List<CourseFileVo> fileVos = courseFileVos.stream().filter(item -> ObjectUtils.isNotNull(item.getParentId()) && item.getParentId() == 0L).collect(Collectors.toList());
             if (!CollectionUtils.isEmpty(fileVos)) {
                 fileVos.forEach(file -> {
                     assembleFile(file, courseFileVos,true);