Tentei mapear um DTO (Student) para um DAO (StudentEntity) usando o método convertValue do ObjectMapper:
new ObjectMapper().convertValue(student, StudentEntity.class);
Entretanto, encontrei a seguinte exceção:
2024-09-20T20:48:01.063+05:30 INFO 10444 --- [nio-8080-exec-2] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring DispatcherServlet 'dispatcherServlet'
2024-09-20T20:48:01.064+05:30 INFO 10444 --- [nio-8080-exec-2] o.s.web.servlet.DispatcherServlet : Initializing Servlet 'dispatcherServlet'
2024-09-20T20:48:01.065+05:30 INFO 10444 --- [nio-8080-exec-2] o.s.web.servlet.DispatcherServlet : Completed initialization in 1 ms
2024-09-20T20:48:01.210+05:30 ERROR 10444 --- [nio-8080-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: java.lang.IllegalArgumentException: Unrecognized field "firstName" (class com.icet.dao.StudentEntity), not marked as ignorable (0 known properties: ])
at [Source: UNKNOWN; byte offset: #UNKNOWN] (through reference chain: com.icet.dao.StudentEntity["firstName"])] with root cause
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "firstName" (class com.icet.dao.StudentEntity), not marked as ignorable (0 known properties: ])
at [Source: UNKNOWN; byte offset: #UNKNOWN] (through reference chain: com.icet.dao.StudentEntity["firstName"])
Mas depois de adicionar a @JsonIgnoreProperties(ignoreUnknown = true)
anotação à classe StudentEntity, a exceção não ocorreu.
Minha pergunta é: quais são as possíveis razões para essa exceção e por que adicionar @JsonIgnoreProperties(ignoreUnknown = true)
resolve o problema?
Classe de entidade:
package com.icet.dao;
import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
import jakarta.persistence.*;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.NoArgsConstructor;
import lombok.ToString;
@Builder
@Entity
@Table(name = "student")
@NoArgsConstructor
@AllArgsConstructor
@ToString
public class StudentEntity {
@Id
@GeneratedValue(strategy = GenerationType.AUTO)
Long id;
private String firstName;
private String lastName;
private String address;
private String phoneNumber;
private String nic;
private String email;
private String batch;
private String age;
}
Classe de Estudante:
package com.icet.model;
import lombok.AllArgsConstructor;
import lombok.Builder;
import lombok.Data;
@Data
@AllArgsConstructor
@Builder
public class Student {
private String firstName;
private String lastName;
private String address;
private String phoneNumber;
private String nic;
private String email;
private String batch;
private String age;
}
Método de classe de serviço que mapeou objeto:
public void registerStudent(Student student) {
StudentEntity entity1 = new ObjectMapper()
.convertValue(student,StudentEntity.class);
//log.info(entity1.toString());
repository.save(entity1);
}
Rastreamento de pilha completa:
2024-09-20T20:48:01.063+05:30 INFO 10444 --- [nio-8080-exec-2] o.a.c.c.C.[Tomcat].[localhost].[/] : Initializing Spring DispatcherServlet 'dispatcherServlet'
2024-09-20T20:48:01.064+05:30 INFO 10444 --- [nio-8080-exec-2] o.s.web.servlet.DispatcherServlet : Initializing Servlet 'dispatcherServlet'
2024-09-20T20:48:01.065+05:30 INFO 10444 --- [nio-8080-exec-2] o.s.web.servlet.DispatcherServlet : Completed initialization in 1 ms
2024-09-20T20:48:01.210+05:30 ERROR 10444 --- [nio-8080-exec-2] o.a.c.c.C.[.[.[/].[dispatcherServlet] : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed: java.lang.IllegalArgumentException: Unrecognized field "firstName" (class com.icet.dao.StudentEntity), not marked as ignorable (0 known properties: ])
at [Source: UNKNOWN; byte offset: #UNKNOWN] (through reference chain: com.icet.dao.StudentEntity["firstName"])] with root cause
com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException: Unrecognized field "firstName" (class com.icet.dao.StudentEntity), not marked as ignorable (0 known properties: ])
at [Source: UNKNOWN; byte offset: #UNKNOWN] (through reference chain: com.icet.dao.StudentEntity["firstName"])
at com.fasterxml.jackson.databind.exc.UnrecognizedPropertyException.from(UnrecognizedPropertyException.java:61) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.DeserializationContext.handleUnknownProperty(DeserializationContext.java:1153) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.deser.std.StdDeserializer.handleUnknownProperty(StdDeserializer.java:2241) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownProperty(BeanDeserializerBase.java:1793) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.deser.BeanDeserializerBase.handleUnknownVanilla(BeanDeserializerBase.java:1771) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.deser.BeanDeserializer.vanillaDeserialize(BeanDeserializer.java:316) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.deser.BeanDeserializer.deserialize(BeanDeserializer.java:177) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.ObjectMapper._convert(ObjectMapper.java:4619) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.fasterxml.jackson.databind.ObjectMapper.convertValue(ObjectMapper.java:4555) ~[jackson-databind-2.17.2.jar:2.17.2]
at com.icet.service.impl.StudentServiceImpl.registerStudent(StudentServiceImpl.java:27) ~[classes/:na]
at com.icet.controller.StudentController.registerStudent(StudentController.java:20) ~[classes/:na]
at java.base/jdk.internal.reflect.DirectMethodHandleAccessor.invoke(DirectMethodHandleAccessor.java:103) ~[na:na]
at java.base/java.lang.reflect.Method.invoke(Method.java:580) ~[na:na]
at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:255) ~[spring-web-6.1.12.jar:6.1.12]
at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:188) ~[spring-web-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:118) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:926) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:831) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1089) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:979) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1014) ~[spring-webmvc-6.1.12.jar:6.1.12]
at org.springframework.web.servlet.FrameworkServlet.doPost(FrameworkServlet.java:914) ~[spring-webmvc-6.1.12.jar:6.1.12]
at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:590) ~[tomcat-embed-core-10.1.28.jar:6.0]
at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:885) ~[spring-webmvc-6.1.12.jar:6.1.12]
at jakarta.servlet.http.HttpServlet.service(HttpServlet.java:658) ~[tomcat-embed-core-10.1.28.jar:6.0]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:195) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:51) ~[tomcat-embed-websocket-10.1.28.jar:10.1.28]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-6.1.12.jar:6.1.12]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.12.jar:6.1.12]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-6.1.12.jar:6.1.12]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.12.jar:6.1.12]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-6.1.12.jar:6.1.12]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:116) ~[spring-web-6.1.12.jar:6.1.12]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:164) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:140) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:167) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:90) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:483) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:115) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:93) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:74) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:344) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:384) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:63) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:904) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1741) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:52) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.tomcat.util.threads.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1190) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.tomcat.util.threads.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:659) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:63) ~[tomcat-embed-core-10.1.28.jar:10.1.28]
at java.base/java.lang.Thread.run(Thread.java:1583) ~[na:na]
Começarei dizendo que este não é um design ideal para mapear seu domínio de negócios para entidades. Existem bibliotecas mais adequadas para esta tarefa que podem ser incorporadas ao design da camada de persistência do seu aplicativo para automatizar o mapeamento de forma eficiente. (Mas se este for apenas um projeto básico, não vejo razão para mudar sua implementação)
Quanto ao seu problema, a conversão está falhando porque não há setters na classe de entidade. Adicione
@Data
ou@Setter
faça uma anotação na entidade ou setters individuais para os campos e funcionará conforme o esperado. Apenas esteja ciente de que a conversão de volta paraStudent
exigirá getters na classe de entidade também.O motivo pelo qual funciona ao ignorar propriedades desconhecidas é porque, como não há setters na entidade, cada propriedade em
Student
é desconhecida paraStudentEntity
. Ao executar a conversão com essa anotação, nenhuma das propriedades é realmente mapeada para a classe de entidade.Resposta simples:
Setter e getter são necessários para o Jackson ObjectMapper, que está faltando na sua classe Entity ao fazer a conversão.
Por favor, adicione
@Getter
e@Setter
de Lombok no topo da classe Entity.