Spring boot Jackson JSON Parse Error : no int/Int-argument constructor/factory method to deserialize-CodePudding

My Connections Entity Model looks like this

@Entity
@Getter@Setter@AllArgsConstructor@NoArgsConstructor
public class Connections implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    private Long id;

    @ManyToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    private MyUsers receiver;

    @OneToOne(fetch = FetchType.LAZY, cascade = CascadeType.ALL)
    private MyUsers sender;

    private boolean accepted

    private boolean following;
}

And my MyUsers Model entity class looks like this

@Entity
@Getter @Setter @NoArgsConstructor @AllArgsConstructor
@Table(name = "my_users")
public class MyUsers implements Serializable {
    @Id
    @GeneratedValue(strategy = GenerationType.AUTO)
    @Column(nullable = false)
    private Long id;
    @Column(nullable = false, unique = true)
    private String userName;

    private String password;
    
    @OneToMany(fetch = FetchType.LAZY, mappedBy = "myUsers", cascade = CascadeType.ALL)
    @JsonIgnore
    private List<Blogs> blogs;

    @OneToMany(fetch = FetchType.LAZY, mappedBy = "receiver", cascade = CascadeType.ALL)
    @JsonIgnore
    private List<Connections> connections;
}

And the JSON POST Request Body to Connection API looks like this,

{
    "receiver": 1,
    "sender": 2,
    "following": 1,
    "accepted": 1
}

When I request I get this error

{
    "timestamp": "2022-07-18T17:24:47.330 00:00",
    "status": 400,
    "error": "Bad Request",
    "trace": "org.springframework.http.converter.HttpMessageNotReadableException: JSON parse error: Cannot construct instance of `me.protik.simplyblog.models.MyUsers` (although at least one Creator exists): no int/Int-argument constructor/factory method to deserialize from Number value (9); nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `me.protik.simplyblog.models.MyUsers` (although at least one Creator exists): no int/Int-argument constructor/factory method to deserialize from Number value (9)\n at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 2, column: 17] (through reference chain: me.protik.simplyblog.models.Connections[\"receiver\"])\n\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:391)\n\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.read(AbstractJackson2HttpMessageConverter.java:343)\n\tat org.springframework.web.servlet.mvc.method.annotation.AbstractMessageConverterMethodArgumentResolver.readWithMessageConverters(AbstractMessageConverterMethodArgumentResolver.java:185)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.readWithMessageConverters(RequestResponseBodyMethodProcessor.java:160)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestResponseBodyMethodProcessor.resolveArgument(RequestResponseBodyMethodProcessor.java:133)\n\tat org.springframework.web.method.support.HandlerMethodArgumentResolverComposite.resolveArgument(HandlerMethodArgumentResolverComposite.java:122)\n\tat org.springframework.web.method.support.InvocableHandlerMethod.getMethodArgumentValues(InvocableHandlerMethod.java:179)\n\tat org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:146)\n\tat org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:117)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:895)\n\tat org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808)\n\tat org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)\n\tat org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1067)\n\tat org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:963)\n\tat org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)\n\tat org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:909)\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:681)\n\tat org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)\n\tat javax.servlet.http.HttpServlet.service(HttpServlet.java:764)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:111)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:327)\n\tat org.springframework.security.web.access.intercept.FilterSecurityInterceptor.invoke(FilterSecurityInterceptor.java:115)\n\tat org.springframework.security.web.access.intercept.FilterSecurityInterceptor.doFilter(FilterSecurityInterceptor.java:81)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:122)\n\tat org.springframework.security.web.access.ExceptionTranslationFilter.doFilter(ExceptionTranslationFilter.java:116)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:126)\n\tat org.springframework.security.web.session.SessionManagementFilter.doFilter(SessionManagementFilter.java:81)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.authentication.AnonymousAuthenticationFilter.doFilter(AnonymousAuthenticationFilter.java:109)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.servletapi.SecurityContextHolderAwareRequestFilter.doFilter(SecurityContextHolderAwareRequestFilter.java:149)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.savedrequest.RequestCacheAwareFilter.doFilter(RequestCacheAwareFilter.java:63)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat me.protik.simplyblog.auth.filters.JwtRequestFilter.doFilterInternal(JwtRequestFilter.java:50)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:103)\n\tat org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:89)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:90)\n\tat org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:75)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:112)\n\tat org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:82)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:55)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.session.DisableEncodeUrlFilter.doFilterInternal(DisableEncodeUrlFilter.java:42)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:336)\n\tat org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:211)\n\tat org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:183)\n\tat org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:354)\n\tat org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:267)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201)\n\tat org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:117)\n\tat org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189)\n\tat org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162)\n\tat org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:197)\n\tat org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97)\n\tat org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:541)\n\tat org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:135)\n\tat org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92)\n\tat org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78)\n\tat org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:360)\n\tat org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:399)\n\tat org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65)\n\tat org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:890)\n\tat org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1787)\n\tat org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)\n\tat org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1191)\n\tat org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659)\n\tat org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)\n\tat java.base/java.lang.Thread.run(Thread.java:833)\nCaused by: com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `me.protik.simplyblog.models.MyUsers` (although at least one Creator exists): no int/Int-argument constructor/factory method to deserialize from Number value (9)\n at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 2, column: 17] (through reference chain: me.protik.simplyblog.models.Connections[\"receiver\"])\n\tat com.fasterxml.jackson.databind.exc.MismatchedInputException.from(MismatchedInputException.java:63)\n\tat com.fasterxml.jackson.databind.DeserializationContext.reportInputMismatch(DeserializationContext.java:1728)\n\tat com.fasterxml.jackson.databind.DeserializationContext.handleMissingInstantiator(DeserializationContext.java:1353)\n\tat com.fasterxml.jackson.databind.deser.ValueInstantiator.createFromInt(ValueInstantiator.java:324)\n\tat com.fasterxml.jackson.databind.deser.std.StdValueInstantiator.createFromInt(StdValueInstantiator.java:376)\n\tat com.fasterxml.jackson.databind.deser.BeanDeserializerBase.deserializeFromNumber(BeanDeserializerBase.java:1442)\n\tat com.fasterxml.jackson.databind.deser.BeanDeserializer._deserializeOther(BeanDeserializer.java:198)\n\tat com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:186)\n\tat com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeAndSet(MethodProperty.java:129)\n\tat com.fasterxml.jackson.databind.deser.BeanDeserializer.deserializeFromObject(BeanDeserializer.java:391)\n\tat com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:184)\n\tat com.fasterxml.jackson.databind.deser.DefaultDeserializationContext.readRootValue(DefaultDeserializationContext.java:323)\n\tat com.fasterxml.jackson.databind.ObjectMapper._readMapAndClose(ObjectMapper.java:4674)\n\tat com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:3682)\n\tat org.springframework.http.converter.json.AbstractJackson2HttpMessageConverter.readJavaType(AbstractJackson2HttpMessageConverter.java:380)\n\t... 95 more\n",
    "message": "JSON parse error: Cannot construct instance of `me.protik.simplyblog.models.MyUsers` (although at least one Creator exists): no int/Int-argument constructor/factory method to deserialize from Number value (9); nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of `me.protik.simplyblog.models.MyUsers` (although at least one Creator exists): no int/Int-argument constructor/factory method to deserialize from Number value (9)\n at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 2, column: 17] (through reference chain: me.protik.simplyblog.models.Connections[\"receiver\"])",
    "path": "/user/connections/add"
}

only if I remove sender and receiver from JSON the API works.

All my entity classes contains getters and setters and constructors from Lombok and also user instance for user_id 1 and 2 exists in my MySQL db

CodePudding user response：

In your JSON you are sending a number

"receiver": 1,

But in your entity class you expect the object

private MyUsers receiver;

There is no way to deserialize 1 to complex object.

If 1 and 2 are the IDs in the database and you hope that this will be magically deserialized - it's not how it works

CodePudding user response：

I'm answering my own question since I have just figured out a workaround, though far from an ideal design, it just works for now.

I added an extra class with other model class without annotating with @Entity(So JPA and Hibernate have nothing to do with it) and calling it ConnectionsWrapper (I don't know naming conventions well :| )

@Getter@Setter@AllArgsConstructor@NoArgsConstructor
public class ConnectionsWrapper implements Serializable {
    private Long receiver;
    private Long sender;
    private boolean accepted;
    private boolean following;
}

Then in the controller's Add/Modify Connection API I'm just parsing the ConnectionWrapper Class model type JSON using @RequestBody and then creating a new original Connections instance and setting datas using information from JSON request body of ConnectionWrapper type then saving the new Connections type Object in the database through Service and Repository functions.

@PostMapping("/user/connections/add")
    public void addModConnection(@RequestBody ConnectionsWrapper connectionsWrapper){
        Connections connection = new Connections();
        connection.setReceiver(myUsersService.showUserByIdService(connectionsWrapper.getReceiver()));
        connection.setSender(myUsersService.showUserByIdService(connectionsWrapper.getSender()));
        connection.setAccepted(connectionsWrapper.isAccepted());
        connection.setFollowing(connection.isFollowing());
        myUsersService.addModConnectionService(connection);
    }