fix 修复 翻译模块 无法翻译实体属性值为 Null 的字段的问题

ruoyi-common/ruoyi-common-translation/src/main/java/com/ruoyi/common/translation/config/TranslationConfig.java

@@ -3,6 +3,7 @@ package com.ruoyi.common.translation.config;
 import com.fasterxml.jackson.databind.ObjectMapper;
 import com.ruoyi.common.translation.annotation.TranslationType;
 import com.ruoyi.common.translation.core.TranslationInterface;
+import com.ruoyi.common.translation.core.handler.TranslationBeanSerializerModifier;
 import com.ruoyi.common.translation.core.handler.TranslationHandler;
 import jakarta.annotation.PostConstruct;
 import lombok.extern.slf4j.Slf4j;
@@ -40,8 +41,10 @@ public class TranslationConfig {
             }
         }
         TranslationHandler.TRANSLATION_MAPPER.putAll(map);
-        // todo null值处理
-//        objectMapper.getSerializerProvider().setNullValueSerializer();
+        // 设置 Bean 序列化修改器
+        objectMapper.setSerializerFactory(
+            objectMapper.getSerializerFactory()
+                .withSerializerModifier(new TranslationBeanSerializerModifier()));
     }
 
 }

ruoyi-common/ruoyi-common-translation/src/main/java/com/ruoyi/common/translation/core/handler/TranslationBeanSerializerModifier.java

@@ -0,0 +1,29 @@
+package com.ruoyi.common.translation.core.handler;
+
+import com.fasterxml.jackson.databind.BeanDescription;
+import com.fasterxml.jackson.databind.SerializationConfig;
+import com.fasterxml.jackson.databind.ser.BeanPropertyWriter;
+import com.fasterxml.jackson.databind.ser.BeanSerializerModifier;
+
+import java.util.List;
+
+/**
+ * Bean 序列化修改器 解决 Null 被单独处理问题
+ *
+ * @author Lion Li
+ */
+public class TranslationBeanSerializerModifier extends BeanSerializerModifier {
+
+    @Override
+    public List<BeanPropertyWriter> changeProperties(SerializationConfig config, BeanDescription beanDesc,
+                                                     List<BeanPropertyWriter> beanProperties) {
+        for (BeanPropertyWriter writer : beanProperties) {
+            // 如果序列化器为 TranslationHandler 的话 将 Null 值也交给他处理
+            if (writer.getSerializer() instanceof TranslationHandler serializer) {
+                writer.assignNullSerializer(serializer);
+            }
+        }
+        return beanProperties;
+    }
+
+}

ruoyi-common/ruoyi-common-translation/src/main/java/com/ruoyi/common/translation/core/handler/TranslationHandler.java

@@ -41,10 +41,15 @@ public class TranslationHandler extends JsonSerializer<Object> implements Contex
             if (StringUtils.isNotBlank(translation.mapper())) {
                 value = ReflectUtils.invokeGetter(gen.getCurrentValue(), translation.mapper());
             }
+            // 如果为 null 直接写出
+            if (ObjectUtil.isNull(value)) {
+                gen.writeNull();
+                return;
+            }
             String result = trans.translation(value, translation.other());
-            gen.writeString(StringUtils.isNotBlank(result) ? result : value.toString());
+            gen.writeString(result);
         } else {
-            gen.writeString(value.toString());
+            gen.writeObject(value);
         }
     }
 

ruoyi-modules/ruoyi-demo/src/main/java/com/ruoyi/demo/domain/vo/TestDemoVo.java

@@ -69,10 +69,16 @@ public class TestDemoVo implements Serializable {
     /**
      * 创建人
      */
-    @Translation(type = TransConstant.USER_ID_TO_NAME)
     @ExcelProperty(value = "创建人")
     private Long createBy;
 
+    /**
+     * 创建人账号
+     */
+    @Translation(type = TransConstant.USER_ID_TO_NAME, mapper = "createBy")
+    @ExcelProperty(value = "创建人账号")
+    private String createByName;
+
     /**
      * 更新时间
      */
@@ -86,5 +92,11 @@ public class TestDemoVo implements Serializable {
     @ExcelProperty(value = "更新人")
     private Long updateBy;
 
+    /**
+     * 更新人账号
+     */
+    @Translation(type = TransConstant.USER_ID_TO_NAME, mapper = "updateBy")
+    @ExcelProperty(value = "更新人账号")
+    private String updateByName;
 
 }

ruoyi-modules/ruoyi-system/src/main/java/com/ruoyi/system/domain/vo/SysNoticeVo.java

@@ -61,7 +61,7 @@ public class SysNoticeVo implements Serializable {
      * 创建人名称
      */
     @Translation(type = TransConstant.USER_ID_TO_NAME, mapper = "createBy")
-    private String createByName = "";
+    private String createByName;
 
     /**
      * 创建时间

ruoyi-ui/src/views/demo/demo/index.vue

@@ -107,13 +107,13 @@
           <span>{{ parseTime(scope.row.createTime, '{y}-{m}-{d}') }}</span>
         </template>
       </el-table-column>
-      <el-table-column label="创建人" align="center" prop="createBy" />
+      <el-table-column label="创建人" align="center" prop="createByName" />
       <el-table-column label="更新时间" align="center" prop="updateTime" width="180">
         <template slot-scope="scope">
           <span>{{ parseTime(scope.row.updateTime, '{y}-{m}-{d}') }}</span>
         </template>
       </el-table-column>
-      <el-table-column label="更新人" align="center" prop="updateBy" />
+      <el-table-column label="更新人" align="center" prop="updateByName" />
       <el-table-column label="操作" align="center" class-name="small-padding fixed-width">
         <template slot-scope="scope">
           <el-button