Spring REST，JSON“无法处理托管/后向引用’defaultReference’”415不支持的媒体类型
我正在尝试使用Spring boot / Spring RestController后端从AngularJS前端POST到http：// localhost：9095 / translators 。
我可以做一个GET，响应如下：
[{"userId":1,"firstName":"John","lastName":"Doe","emailId":"john.doe@inc.com","languages":[{"languageId":1,"languageCode":"gb","source":true}],"translations":[{"translationId":3,"sourceId":1,"sourceText":"Hello","targetId":null,"targetText":null,"translationStatus":"DUE"}],"userType":"TRANSLATOR"} 当我发布下面的json时，我得到了错误响应
发布数据：
{ firstName: "zen", lastName: "cv", emailId: "email", userType: "TRANSLATOR", languages : [{languageId:1,languageCode:"gb",source:true}] }
错误：
{ timestamp: 1422389312497 status: 415 error: "Unsupported Media Type" exception: "org.springframework.web.HttpMediaTypeNotSupportedException" message: "Content type 'application/json' not supported" path: "/translators" }
我确保我的控制器具有正确的Mediatype注释。
@RestController @RequestMapping("/translators") public class TranslatorController { @Autowired private UserRepository repository; @RequestMapping(method = RequestMethod.GET) public List findUsers() { return repository.findAll(); } @RequestMapping(value = "/{userId}", method = RequestMethod.GET) public User findUser(@PathVariable Long userId) { return repository.findOne(userId); } @RequestMapping(method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE) public User addTranslator(@RequestBody User user) { //translation.setTranslationId(null); return repository.saveAndFlush(user); } @RequestMapping(value = "/{translatorId}", method = RequestMethod.PUT) public User updateTranslation(@RequestBody User updatedUser, @PathVariable Long userId) { //updatedTranslation.setTranslationId(translationId); return repository.saveAndFlush(updatedUser); } @RequestMapping(value = "/{translatorId}", method = RequestMethod.DELETE) public void deleteTranslation(@PathVariable Long translationId) { repository.delete(translationId); } }
经过一些研究，并通过查看日志输出，我意识到这是一个误导性的错误消息，问题实际上是在序列化/反序列化Json时发生的
在日志文件中，我发现
2015-01-27 21：08：32.488 WARN 15152 — [nio-9095-exec-1] .cjMappingJackson2HttpMessageConverter：无法评估类型[simple type，class User]的反序列化：java.lang.IllegalArgumentException：无法处理托管/后向引用’defaultReference’：与托管类型（User）不兼容的后引用类型（java.util.List）
这是我的类用户和类翻译（为了简洁省略了getter，setter，constructor等）
@Entity @Table(name = "users") public class User { @Id @GeneratedValue(strategy= GenerationType.AUTO) @Column(name = "user_id") private long userId; @Column(name = "first_name") private String firstName; @Column(name = "last_name") private String lastName; @Column(name = "email_id") private String emailId; @ManyToMany @JoinTable(name = "languages_users", joinColumns = { @JoinColumn(name = "user_id")}, inverseJoinColumns = {@JoinColumn(name = "lang_id")}) @JsonManagedReference private List languages = new ArrayList(); @OneToMany(mappedBy = "translator", fetch = FetchType.EAGER) @JsonManagedReference private List translations; @Enumerated(EnumType.STRING) private UserType userType; } @Entity @Table(name = "translations") public class Translation { @Id @GeneratedValue(strategy= GenerationType.IDENTITY) @Column(name = "translation_id") private Long translationId; @Column(name = "source_lang_id") private Long sourceId; @Column(name = "source_text") private String sourceText; @Column(name = "target_lang_id") private Long targetId; @Column(name = "target_text") private String targetText; @Enumerated(EnumType.STRING) @Column(name = "status") private TranslationStatus translationStatus; @ManyToOne @JoinColumn(name = "translator_id") @JsonBackReference private User translator; }
我的问题是：如何为上述实体正确设置JsonManagedReference和JsonBackReference？ 我确实读过这份文件。 我根据错误信息无法弄清楚这里有什么问题
对于那些要求，另一种方法是使用fasterxml的JsonIdentityInfo并使用以下方法注释您的类：
import com.fasterxml.jackson.annotation.JsonIdentityInfo; import com.fasterxml.jackson.annotation.ObjectIdGenerators; @JsonIdentityInfo(generator=ObjectIdGenerators.PropertyGenerator.class, property="id") public class Account implements java.io.Serializable { .... private Long id; }
*没有足够的代表评论。
我通过摆脱JsonManagedReference和JsonBackReference并用JsonIdentityInfo替换它来解决它
正如@Sharppoint在评论中所说，我通过删除@JsonManagedReference解决了我的问题，但保留@JsonBackReference 。
您需要@ResponseBody注释，如下所示：
@RequestMapping(method = RequestMethod.POST, consumes = MediaType.APPLICATION_JSON_VALUE, produces = MediaType.APPLICATION_JSON_VALUE) @ResponseBody public User addTranslator(@RequestBody User user) { //translation.setTranslationId(null); return repository.saveAndFlush(user); }
我有同样的错误，我解决了删除所有注释@JsonBackReference和@JsonManagedReference，然后我把@JsonIdentityInfo放在我的所有关系中与关系检查文档