feature: 增加实体基类，开启字段自动填充

Author: Dallas98

backend/services/data-management-service/src/main/java/com/dataengine/datamanagement/domain/model/dataset/Dataset.java

@@ -1,8 +1,8 @@
 package com.dataengine.datamanagement.domain.model.dataset;
 
 import com.baomidou.mybatisplus.annotation.TableField;
-import com.baomidou.mybatisplus.annotation.TableId;
 import com.baomidou.mybatisplus.annotation.TableName;
+import com.dataengine.common.domain.model.base.BaseEntity;
 import lombok.Getter;
 import lombok.Setter;
 
@@ -18,38 +18,23 @@
 @Getter
 @Setter
 @TableName(value = "t_dm_datasets", autoResultMap = true)
-public class Dataset {
-    @TableId
-    private String id;
+public class Dataset extends BaseEntity<String> {
     private String name;
     private String description;
-    // DB: dataset_type
     private String datasetType;
-
     private String category;
-
-    // DB: path
     private String path;
-    // DB: format
     private String format;
     private String schemaInfo;
-
-    // DB: size_bytes
     private Long sizeBytes = 0L;
     private Long fileCount = 0L;
     private Long recordCount = 0L;
     private Integer retentionDays = 0;
-
     private String metadata;
-
     private String status; // DRAFT/ACTIVE/ARCHIVED/PROCESSING
     private Boolean isPublic = false;
     private Boolean isFeatured = false;
     private Long version = 0L;
-    private LocalDateTime createdAt;
-    private LocalDateTime updatedAt;
-    private String createdBy;
-    private String updatedBy;
 
     // 聚合内的便捷集合（非持久化关联，由应用服务填充）
     @TableField(exist = false)

backend/services/data-management-service/src/main/java/com/dataengine/datamanagement/interfaces/rest/DatasetTypeController.java

@@ -44,13 +44,13 @@ private DatasetTypeResponse createDatasetType(String code, String name, String d
     }
 
     private String getIconForType(String typeCode) {
-        switch (typeCode) {
-            case "IMAGE": return "🖼️";
-            case "TEXT": return "📄";
-            case "AUDIO": return "🎵";
-            case "VIDEO": return "🎬";
-            case "MULTIMODAL": return "📊";
-            default: return "📁";
-        }
+        return switch (typeCode) {
+            case "IMAGE" -> "🖼️";
+            case "TEXT" -> "📄";
+            case "AUDIO" -> "🎵";
+            case "VIDEO" -> "🎬";
+            case "MULTIMODAL" -> "📊";
+            default -> "📁";
+        };
     }
 }

backend/shared/domain-common/src/main/java/com/dataengine/common/domain/AggregateRoot.java

@@ -1,26 +1,25 @@
 package com.dataengine.common.domain;
 
-import java.time.LocalDateTime;
-import java.util.Objects;
+import com.dataengine.common.domain.model.base.BaseEntity;
 
 /**
  * DDD聚合根基类
  */
-public abstract class AggregateRoot<ID> extends Entity<ID> {
-    
+public abstract class AggregateRoot<ID> extends BaseEntity<ID> {
+
     protected AggregateRoot() {
         super();
     }
-    
+
     protected AggregateRoot(ID id) {
         super(id);
     }
-    
+
     /**
      * 获取聚合版本号（用于乐观锁）
      */
     public abstract Long getVersion();
-    
+
     /**
      * 设置聚合版本号
      */

backend/shared/domain-common/src/main/java/com/dataengine/common/domain/Entity.java

@@ -0,0 +1,46 @@
+package com.dataengine.common.domain.model.base;
+
+import com.baomidou.mybatisplus.annotation.FieldFill;
+import com.baomidou.mybatisplus.annotation.IdType;
+import com.baomidou.mybatisplus.annotation.TableField;
+import com.baomidou.mybatisplus.annotation.TableId;
+import lombok.Getter;
+import lombok.NoArgsConstructor;
+import lombok.Setter;
+
+import java.io.Serial;
+import java.io.Serializable;
+import java.time.LocalDateTime;
+
+/**
+ * 实体基类
+ *
+ * @param <ID> 实体ID类型
+ */
+@Getter
+@Setter
+@NoArgsConstructor
+public abstract class BaseEntity<ID> implements Serializable {
+    @Serial
+    private static final long serialVersionUID = 1L;
+
+    @TableId(type = IdType.ASSIGN_ID)
+    protected ID id;
+
+    @TableField(fill = FieldFill.INSERT)
+    protected LocalDateTime createdAt;
+
+    @TableField(fill = FieldFill.INSERT_UPDATE)
+    protected LocalDateTime updatedAt;
+
+    @TableField(fill = FieldFill.INSERT)
+    protected String createdBy;
+
+    @TableField(fill = FieldFill.INSERT_UPDATE)
+    protected String updatedBy;
+
+    public BaseEntity(ID id) {
+        super();
+        this.id = id;
+    }
+}

backend/shared/domain-common/src/main/java/com/dataengine/common/domain/model/base/BaseEntity.java

@@ -0,0 +1,60 @@
+package com.dataengine.common.infrastructure.config;
+
+import com.baomidou.mybatisplus.core.handlers.MetaObjectHandler;
+import lombok.extern.slf4j.Slf4j;
+import org.apache.ibatis.reflection.MetaObject;
+import org.springframework.context.annotation.Configuration;
+
+import java.time.LocalDateTime;
+
+/**
+ * 持久化实体元数据对象处理器
+ *
+ * @author dallas
+ * @since 2025-10-17
+ */
+@Slf4j
+@Configuration
+public class EntityMetaObjectHandler implements MetaObjectHandler {
+    @Override
+    public void insertFill(MetaObject metaObject) {
+        log.debug("Starting insert fill...");
+
+        // 创建时间填充
+        this.strictInsertFill(metaObject, "createdAt", LocalDateTime.class, LocalDateTime.now());
+        // 更新时间填充
+        this.strictInsertFill(metaObject, "updatedAt", LocalDateTime.class, LocalDateTime.now());
+        // 创建人填充（需要从安全上下文获取当前用户）
+        String currentUser = getCurrentUser();
+        this.strictInsertFill(metaObject, "createdBy", String.class, currentUser);
+        // 更新人填充
+        this.strictInsertFill(metaObject, "updatedBy", String.class, currentUser);
+    }
+
+    @Override
+    public void updateFill(MetaObject metaObject) {
+        log.debug("Starting update fill...");
+        // 更新时间填充
+        this.strictUpdateFill(metaObject, "updatedAt", LocalDateTime.class, LocalDateTime.now());
+        // 更新人填充
+        this.strictUpdateFill(metaObject, "updatedBy", String.class, getCurrentUser());
+    }
+
+    /**
+     * 获取当前用户（需要根据你的安全框架实现）
+     */
+    private String getCurrentUser() {
+        // todo 这里需要根据你的安全框架实现，例如Spring Security、Shiro等
+        // 示例：返回默认用户或从SecurityContext获取
+        try {
+            // 如果是Spring Security
+            // return SecurityContextHolder.getContext().getAuthentication().getName();
+
+            // 临时返回默认值，请根据实际情况修改
+            return "system";
+        } catch (Exception e) {
+            log.error("Error getting current user", e);
+            return "unknown";
+        }
+    }
+}