spring-boot-starter-data-elasticsearch 中测试查询语句报错failed to map source

报错信息：

org.springframework.data.elasticsearch.ElasticsearchException: failed to map source [ {"id":5,"title":"荣耀V10","category":"手机","brand":"华为","price":2799.0,"images":"http://image.baidu.com/13123.jpg"}] to class Item

出现这种情况是没有加无参构造器：