Java Spring:获取多个实体时,引用实体(OneToMany)不会显示在JSON中

Java Spring:获取多个实体时,引用实体(OneToMany)不会显示在JSON中,java,json,spring,spring-mvc,spring-data-jpa,Java,Json,Spring,Spring Mvc,Spring Data Jpa,当我在POSTMAN中发送GET请求以获取所有子实体时,JSON响应中不会显示父实体省 这是我的控制器 @RequestMapping(value ="api/v1/town",method = RequestMethod.GET) public ResponseEntity<List<Town>> getAllTowns() { List<Town> towns = townService.getAllTowns(); if(towns.is

当我在POSTMAN中发送GET请求以获取所有子实体时,JSON响应中不会显示父实体省

这是我的控制器

@RequestMapping(value ="api/v1/town",method = RequestMethod.GET)
public ResponseEntity<List<Town>> getAllTowns() {
    List<Town> towns = townService.getAllTowns();
    if(towns.isEmpty()) {
        return new ResponseEntity<List<Town>>(HttpStatus.NO_CONTENT);
    }

    return new ResponseEntity<List<Town>>(towns, HttpStatus.OK);
}
我得到的回应是这样的

{
    "id" : 1,  
    "name" : "Some Town",
    "kilometer" : 350
}
我期待的是

{
    "id" : 1,  
    "name" : "Some Town",
    "province" : { 
             //Province data.....
     }
    "kilometer" : 350
}
我能够展示这样的东西,但我使用的对象不是Spring数据jpa实体,只是简单的POJO

我的实体有什么问题吗?或者还有别的吗?

交换@JsonBackReference和@JsonManagedReference。基本上:

@JsonManagedReference
private Province province;

@JsonBackReference
private List<Town> towns;

如果我这样做,我的父实体将无法显示子实体。我可以通过引用这个来修复它。
{
    "id" : 1,  
    "name" : "Some Town",
    "province" : { 
             //Province data.....
     }
    "kilometer" : 350
}
@JsonManagedReference
private Province province;

@JsonBackReference
private List<Town> towns;