Spring Boot 集成Hibernate: 外键关系_java springboot hibernate 外键

一对多 vs 多对一

一个存钱罐有很多零钱对吧？

//存钱罐
@Entity
@JsonIgnoreProperties({"hibernateLazyInitializer", "handler"})
public class Pod {
    @Id
    @GeneratedValue
    private Long id;

    // 一个存钱罐有很多零钱
    @OneToMany(cascade = CascadeType.ALL,mappedBy = "pod")
    @JsonManagedReference  //少的一方管理映射，将在测试结果中看出
    private List<Coin> coins;
}
//零钱
@Entity
public class Coin {
    @Id
    @GeneratedValue
    private Long id;

    @ManyToOne  
    //@JoinColumn  //抑制ORM建造多余表
    @JsonBackReference  //设置少的一方管理集合，属性名于mappedBy相对应
    private Pod pod;
}
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还是老规矩写两个Repository，此处省略。

@RestController
@RequestMapping("/pod")
public class ForeignKeyController {

    @Autowired
    PodRepository podRepository;

    @Autowired
    CoinRepository coinRepository;

    @GetMapping("/getPod/{podId}")
    public Pod podInfo(@PathVariable long podId){
        return podRepository.getOne(podId);
    }

    @PostMapping("/addPod")
    public String addPod(@RequestBody Pod pod){
        podRepository.save(pod);
        return "add pod success";
    }

    @PostMapping("/addCoin")
    public String addCoin(@RequestBody Coin coin){
        coinRepository.save(coin);
        return "add coin";
    }
}
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测试：

//添加一个存钱罐
POST localhost:8080/pod/addPod
{
}

POST localhost:8080/pod/addCoin
{
	"pod":{ "id": 11}
}

GET localhost:8080/pod/getPod/11
{
    "id": 11,
    "coins": [
        {
            "id": 14
        }
    ]
}
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