REPORT-62437 安装大数据集导出excel插件后，远程和本地互相切换时保存失败问题

designer-base/src/main/java/com/fr/design/mainframe/JTemplate.java

@@ -406,9 +406,12 @@ public abstract class JTemplate<T extends BaseBook, U extends BaseUndoState<?>>
     }
 
     private void setTargetByFile(FILE file) {
-        this.template = JTemplateFactory.asIOFile(file, this.suffix());
+        T newTemplate = JTemplateFactory.asIOFile(file, this.suffix());
+        if (newTemplate != null) {
+            this.template = newTemplate;
             setTarget(this.template);
         }
+    }
 
     private void addCenterPane() {