MongoDB 不序列化Java属性类问题

Spring boot 是 2.1.0.RELEASE

org.springframework.boot
spring-boot-starter-data-mongodb

<groupId>org.projectlombok</groupId>
<artifactId>lombok</artifactId>
<version>1.18.4</version>
<scope>provided</scope>

<groupId>org.springframework.boot</groupId>
<artifactId>spring-boot-starter-test</artifactId>
<scope>test</scope>

对象不完全序列化
最近在项目中存储数据到 MongoDB 中时，发现对象中属性是对象时不能被自动序列化到 MongoDB 中。数据其实就是快递公司的物流轨迹信息。

数据表现
db.kuaidibird.find()
{ "_id" : ObjectId("5caa1336f2cc84bbd083e942"), "callback" : "1-2-3", "callback_time" : NumberLong(1554650510), "ebussinessid" : "", "iskuaidaoyun" : 1, "logisticcode" : "V0123", "ordercode" : "1-2-3", "reason" : "", "shippercode" : "jd", "state" : "已签收", "subscribe_time" : 0, "success" : false, "traces" : [ { "acceptStation" : "北京亦庄发出", "acceptTime" : "2019-04-01" }, { "acceptStation" : "北京亦庄出库", "acceptTime" : "2019-04-02" }, { "acceptStation" : "北京昌平收货", "acceptTime" : "2019-04-03" }, { "acceptStation" : "北京昌平签收", "acceptTime" : "2019-04-04" } ] }
可以看到对于键 traces 存储的对象未正确序列化，期望是非驼峰，全部小写。

Java Bean 对象
主要对象：

package com.github.zhgxun.learn.common.bean;

import com.google.gson.annotations.SerializedName;
import lombok.Data;

import java.util.List;

@Data
public class LogisticsTraceBean {

// 标识属于快刀云回调产生的信息
@SerializedName("iskuaidaoyun")
private int isKuaidaoyun = 1;

// 快递公司编码, go已经做过一次映射, 需要同步, 未做映射的保留原样, 需要补充到go代码中
@SerializedName("shippercode")
private String shipperCode;

@SerializedName("ebussinessid")
private String ebussinessId = "";

// 格式为 callback := fmt.Sprintf("%v-%v-%v", deliveryId, pid, express)
// ExpressSn 快递单号
// DeliveryId 需要查询ShopDelivery表主键
// pid 查看go代码, 查询 kuaidi100 的逻辑其实并没有处理 pid, 故 pid=0
@SerializedName("ordercode")
private String orderCode;

// 快递单号
@SerializedName("logisticcode")
private String logisticCode;

private boolean success = false;

private String reason;

// 快递状态
// "在途中", "已发货", "疑难件", "已签收", "退签", "派件中", "退回"
private String state;

// 同 orderCode
private String callback;

// 回调操作时间, 当前时间戳
@SerializedName("callback_time")
private Long callbackTime = System.currentTimeMillis() / 1000;

@SerializedName("subscribe_time")
private int subscribeTime = 0;

// 快递跟踪信息
private List<TraceBean> traces;

}
嵌套对象：

package com.github.zhgxun.learn.common.bean;

import com.google.gson.annotations.SerializedName;
import lombok.Data;

@Data
public class TraceBean {

public TraceBean() {

}

public TraceBean(String acceptStation, String acceptTime) {
    this.acceptStation = acceptStation;
    this.acceptTime = acceptTime;
}

// 快递链路信息, 例如 签收成功, 签收人: 杨凯
@SerializedName("acceptstation")
private String acceptStation;

// 当前记录时间 2017-08-16 11:09:01
@SerializedName("accepttime")
private String acceptTime;

}
对象都是用 gson @SerializedName 标识了序列化的期望。

测试代码
package com.github.zhgxun.learn.mongo;

import com.github.zhgxun.learn.common.bean.LogisticsTraceBean;
import com.github.zhgxun.learn.common.bean.TraceBean;
import org.junit.Test;
import org.junit.runner.RunWith;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.test.context.SpringBootTest;
import org.springframework.data.mongodb.core.MongoTemplate;
import org.springframework.data.mongodb.core.query.Criteria;
import org.springframework.data.mongodb.core.query.Query;
import org.springframework.data.mongodb.core.query.Update;
import org.springframework.test.context.junit4.SpringRunner;

import java.util.ArrayList;
import java.util.List;

@RunWith(SpringRunner.class)
@SpringBootTest
public class CheckSerialTest {

@Autowired
private MongoTemplate mongoTemplate;

@Test
public void upsert() {
    List<TraceBean> beans = new ArrayList<>();
    beans.add(new TraceBean("北京亦庄发出", "2019-04-01"));
    beans.add(new TraceBean("北京亦庄出库", "2019-04-02"));
    beans.add(new TraceBean("北京昌平收货", "2019-04-03"));
    beans.add(new TraceBean("北京昌平签收", "2019-04-04"));

    LogisticsTraceBean bean = new LogisticsTraceBean();
    bean.setShipperCode("jd");
    bean.setOrderCode("1-2-3");
    bean.setLogisticCode("V0123");
    bean.setReason("");
    bean.setState("已签收");
    bean.setCallback("1-2-3");
    bean.setTraces(beans);

    Query query = new Query(Criteria.where("callback").is(bean.getCallback()));
    Update update = new Update();
    update.set("iskuaidaoyun", 1);
    // 映射到 MapCode
    update.set("shippercode", bean.getShipperCode());
    // ebussinessid 默认空
    update.set("ebussinessid", bean.getEbussinessId());
    // ordercode
    update.set("ordercode", bean.getOrderCode());
    // logisticcode 快递单号
    update.set("logisticcode", bean.getLogisticCode());
    // success = false
    update.set("success", false);
    // reason 默认空
    update.set("reason", "");
    // state 快递状态
    update.set("state", bean.getState());
    // callback 同 ordercode
    update.set("callback", bean.getCallback());
    // callback_time 当前 UNIX 时间戳
    update.set("callback_time", bean.getCallbackTime());
    // subscribe_time 默认0
    update.set("subscribe_time", 0);
    // traces 快递链路信息
    update.set("traces", bean.getTraces());

    System.out.println(mongoTemplate.upsert(query, update, LogisticsTraceBean.class, "kuaidibird"));
}

}
尝试的方法
编写转换器类：

package com.github.zhgxun.learn.common.converter;

import com.github.zhgxun.learn.common.bean.TraceBean;
import org.bson.Document;
import org.springframework.core.convert.converter.Converter;

public class MongoSerialConverter implements Converter {

@Override
public TraceBean convert(Document source) {
    System.out.println("Source: " + source.toJson());
    Document document = (Document) source.get("traces");
    System.out.println("Document: " + document.toString());
    return null;
}

}
启动类中加入 Bean 注入转换器，但不生效。

@Bean
public MongoCustomConversions mongoCustomConversions() {

System.out.println("Mongo转换器...");
return new MongoCustomConversions(Arrays.asList(new MongoSerialConverter()));

}
期望结果
在不改变 MongoTemplate 使用方式，即是测试用例中的默认模板使用外，如何使属性是对象是也能按期望进行序列化。