数据集添加继承版本功能修复。

application-webadmin/src/main/java/com/yice/webadmin/app/service/impl/DatasetVersionServiceImpl.java

@@ -143,7 +143,7 @@ public class DatasetVersionServiceImpl extends BaseService<DatasetVersion, Long>
     private DatasetVersion dealWithWriteAndSave(Long datasetId, Integer hisVersion,
                                                 Long versionId, String datasetName) throws IOException {
         DatasetVersion datasetVersion = null;
-        if (hisVersion > 0) {
+        if (null != hisVersion && hisVersion > 0) {
             DatasetVersion filter = new DatasetVersion();
             filter.setDatasetVersion(hisVersion);
             filter.setDatasetId(datasetId);