教材管理，查询详情，列表报错解决

src/main/java/com/xjrsoft/module/textbook/controller/TextbookController.java

@@ -61,7 +61,7 @@ public class TextbookController {
     public RT<TextbookVo> info(@RequestParam Long id){
         Textbook textbook = textbookService.getById(id);
         if (textbook == null) {
-           return RT.error("找不到此数据！");
+           return RT.ok();
         }
         textbook.setTextbookClassRelationList(textbookService.getClassRelation(textbook.getId()));
         return RT.ok(BeanUtil.toBean(textbook, TextbookVo.class));
@@ -84,7 +84,7 @@ public class TextbookController {
     public RT<List<TextbookSubscriptionRecordVo>> subscriptionList(@RequestParam Long id){
         List<TextbookSubscriptionRecordVo> result = textbookService.subscriptionList(id);
         if (result == null) {
-            return RT.error("找不到此数据！");
+            return RT.ok(new ArrayList<>());
         }
         return RT.ok(result);
     }
@@ -95,7 +95,7 @@ public class TextbookController {
     public RT<List<TextbookWarehouseRecordListVo>> warehouseList(@RequestParam Long id){
         List<TextbookWarehouseRecordListVo> result = textbookService.warehouseList(id);
         if (result == null) {
-            return RT.error("找不到此数据！");
+            return RT.ok(new ArrayList<>());
         }
         return RT.ok(result);
     }
@@ -106,7 +106,7 @@ public class TextbookController {
     public RT<List<TextbookIssueRecordListVo>> issueList(@RequestParam Long id){
         List<TextbookIssueRecordListVo> result = textbookService.issueList(id);
         if (result == null) {
-            return RT.error("找不到此数据！");
+            return RT.ok(new ArrayList<>());
         }
         return RT.ok(result);
     }
@@ -117,7 +117,7 @@ public class TextbookController {
     public RT<List<WfTextbookClaimListVo>> claimList(@RequestParam Long id){
         List<WfTextbookClaimListVo> result = textbookService.claimList(id);
         if (result == null) {
-            return RT.error("找不到此数据！");
+            return RT.ok(new ArrayList<>());
         }
         return RT.ok(result);
     }
@@ -129,7 +129,7 @@ public class TextbookController {
     public RT<Boolean> add(@Valid @RequestBody AddTextbookDto dto){
         Textbook textbook = BeanUtil.toBean(dto, Textbook.class);
         boolean isSuccess = textbookService.add(textbook);
-    return RT.ok(isSuccess);
+        return RT.ok(isSuccess);
     }
 
     @PutMapping