创建时间字段自动插入问题处理，签到增加访问限制

framework/src/main/java/cn/lili/mybatis/mybatisplus/MyMetaObjectHandler.java

@@ -22,11 +22,15 @@ public class MyMetaObjectHandler implements MetaObjectHandler {
         AuthUser authUser = UserContext.getCurrentUser();
         if (authUser != null) {
             this.setFieldValByName("createBy", authUser.getUsername(), metaObject);
-        }else{
+        } else {
 
             this.setFieldValByName("createBy", "SYSTEM", metaObject);
         }
-        this.setFieldValByName("createTime", new Date(), metaObject);
+        //有创建时间字段，切字段值为空
+        if (metaObject.hasGetter("createTime")
+                && metaObject.getValue("createTime") == null) {
+            this.setFieldValByName("createTime", new Date(), metaObject);
+        }
         //有值，则写入
         if (metaObject.hasGetter("deleteFlag")) {
             this.setFieldValByName("deleteFlag", false, metaObject);