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在Spring实体中使用枚举类型

javamysqlspringspring-bootspring-data-jpa
8

如何设置使用枚举的Spring实体？

我已经建立了一个spring-boot项目并提供了下面的代码，希望有人能告诉我该如何正确地完成这项任务。

我已经设置了一个Spring实体。

    @Entity
    public class Resource {

    @Id
    private String id;
    private String name;
    @Column(name="resourceType")
    private ResourceType type;
    //Getters and setters}

我已经设置了在实体中使用的枚举。

    public enum ResourceType {
    financial("financial"),
    raw("raw"),
    factory("factory"),
    lab("lab");

    String value;

    ResourceType(String value) {
        this.value =value;
    }
    }

我正在使用MySQL，已经设置好了表并添加了数据。

    create table resource
    (
    id           varchar(10) not null,
    name         varchar(30) not null,
    resourceType ENUM('financial','raw','factory','lab')
    );
    insert into resource(id, name, resourceType)
    values 
       ('O', 'Oxygen', 'raw');

如果我运行Spring应用程序并尝试返回所有实体的列表，则会出现问题。

2021-06-03 17:33:16.436  WARN 1508519 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper   : SQL Error: 0, SQLState: 22018
2021-06-03 17:33:16.437 ERROR 1508519 --- [nio-8080-exec-1] o.h.engine.jdbc.spi.SqlExceptionHelper   : Cannot determine value type from string 'raw'
2021-06-03 17:33:16.452 ERROR 1508519 --- [nio-8080-exec-1] o.a.c.c.C.[.[.[/].[dispatcherServlet]    : Servlet.service() for servlet [dispatcherServlet] in context with path [] threw exception [Request processing failed; nested exception is org.springframework.dao.DataIntegrityViolationException: could not execute query; SQL [select resource0_.id as id1_3_, resource0_.name as name2_3_, resource0_.resourceType as resource3_3_ from Resource resource0_]; nested exception is org.hibernate.exception.DataException: could not execute query] with root cause

com.mysql.cj.exceptions.DataConversionException: Cannot determine value type from string 'raw'
    at com.mysql.cj.result.StringConverter.createFromBytes(StringConverter.java:131) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.protocol.a.MysqlTextValueDecoder.decodeByteArray(MysqlTextValueDecoder.java:238) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.protocol.result.AbstractResultsetRow.decodeAndCreateReturnValue(AbstractResultsetRow.java:143) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.protocol.result.AbstractResultsetRow.getValueFromBytes(AbstractResultsetRow.java:250) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.protocol.a.result.ByteArrayRow.getValue(ByteArrayRow.java:91) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.result.ResultSetImpl.getNonStringValueFromRow(ResultSetImpl.java:656) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.result.ResultSetImpl.getInt(ResultSetImpl.java:896) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.mysql.cj.jdbc.result.ResultSetImpl.getInt(ResultSetImpl.java:916) ~[mysql-connector-java-8.0.14.jar:8.0.14]
    at com.zaxxer.hikari.pool.HikariProxyResultSet.getInt(HikariProxyResultSet.java) ~[HikariCP-3.4.5.jar:na]
    at org.hibernate.type.descriptor.sql.IntegerTypeDescriptor$2.doExtract(IntegerTypeDescriptor.java:62) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.type.descriptor.sql.BasicExtractor.extract(BasicExtractor.java:47) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.metamodel.model.convert.internal.OrdinalEnumValueConverter.readValue(OrdinalEnumValueConverter.java:66) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.type.EnumType.nullSafeGet(EnumType.java:250) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.type.CustomType.nullSafeGet(CustomType.java:119) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.type.AbstractType.hydrate(AbstractType.java:91) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.persister.entity.AbstractEntityPersister.hydrate(AbstractEntityPersister.java:3130) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.loadFromResultSet(Loader.java:1869) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.hydrateEntityState(Loader.java:1797) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.instanceNotYetLoaded(Loader.java:1770) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.getRow(Loader.java:1622) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.getRowFromResultSet(Loader.java:740) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.getRowsFromResultSet(Loader.java:1039) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.processResultSet(Loader.java:990) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.doQuery(Loader.java:959) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.doQueryAndInitializeNonLazyCollections(Loader.java:349) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.doList(Loader.java:2849) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.doList(Loader.java:2831) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.listIgnoreQueryCache(Loader.java:2663) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.Loader.list(Loader.java:2658) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.loader.hql.QueryLoader.list(QueryLoader.java:506) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.hql.internal.ast.QueryTranslatorImpl.list(QueryTranslatorImpl.java:400) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.engine.query.spi.HQLQueryPlan.performList(HQLQueryPlan.java:219) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.internal.SessionImpl.list(SessionImpl.java:1414) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.query.internal.AbstractProducedQuery.doList(AbstractProducedQuery.java:1625) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.query.internal.AbstractProducedQuery.list(AbstractProducedQuery.java:1593) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.query.Query.getResultList(Query.java:165) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.hibernate.query.criteria.internal.compile.CriteriaQueryTypeQueryAdapter.getResultList(CriteriaQueryTypeQueryAdapter.java:76) ~[hibernate-core-5.4.30.Final.jar:5.4.30.Final]
    at org.springframework.data.jpa.repository.support.SimpleJpaRepository.findAll(SimpleJpaRepository.java:356) ~[spring-data-jpa-2.4.8.jar:2.4.8]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na]
    at org.springframework.data.repository.core.support.RepositoryMethodInvoker$RepositoryFragmentMethodInvoker.lambda$new$0(RepositoryMethodInvoker.java:289) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.data.repository.core.support.RepositoryMethodInvoker.doInvoke(RepositoryMethodInvoker.java:137) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.data.repository.core.support.RepositoryMethodInvoker.invoke(RepositoryMethodInvoker.java:121) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.data.repository.core.support.RepositoryComposition$RepositoryFragments.invoke(RepositoryComposition.java:524) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.data.repository.core.support.RepositoryComposition.invoke(RepositoryComposition.java:285) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.data.repository.core.support.RepositoryFactorySupport$ImplementationMethodExecutionInterceptor.invoke(RepositoryFactorySupport.java:531) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.doInvoke(QueryExecutorMethodInterceptor.java:156) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.data.repository.core.support.QueryExecutorMethodInterceptor.invoke(QueryExecutorMethodInterceptor.java:131) ~[spring-data-commons-2.4.8.jar:2.4.8]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.transaction.interceptor.TransactionInterceptor$1.proceedWithInvocation(TransactionInterceptor.java:123) ~[spring-tx-5.3.6.jar:5.3.6]
    at org.springframework.transaction.interceptor.TransactionAspectSupport.invokeWithinTransaction(TransactionAspectSupport.java:388) ~[spring-tx-5.3.6.jar:5.3.6]
    at org.springframework.transaction.interceptor.TransactionInterceptor.invoke(TransactionInterceptor.java:119) ~[spring-tx-5.3.6.jar:5.3.6]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.dao.support.PersistenceExceptionTranslationInterceptor.invoke(PersistenceExceptionTranslationInterceptor.java:137) ~[spring-tx-5.3.6.jar:5.3.6]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.data.jpa.repository.support.CrudMethodMetadataPostProcessor$CrudMethodMetadataPopulatingMethodInterceptor.invoke(CrudMethodMetadataPostProcessor.java:174) ~[spring-data-jpa-2.4.8.jar:2.4.8]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.aop.interceptor.ExposeInvocationInterceptor.invoke(ExposeInvocationInterceptor.java:97) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.aop.framework.ReflectiveMethodInvocation.proceed(ReflectiveMethodInvocation.java:186) ~[spring-aop-5.3.6.jar:5.3.6]
    at org.springframework.aop.framework.JdkDynamicAopProxy.invoke(JdkDynamicAopProxy.java:215) ~[spring-aop-5.3.6.jar:5.3.6]
    at com.sun.proxy.$Proxy94.findAll(Unknown Source) ~[na:na]
    at com.astrominer.screepsmarketanalyser.service.ResourcesService.getAll(ResourcesService.java:17) ~[classes/:na]
    at com.astrominer.screepsmarketanalyser.controller.ResourceController.all(ResourceController.java:25) ~[classes/:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:na]
    at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:64) ~[na:na]
    at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:na]
    at java.base/java.lang.reflect.Method.invoke(Method.java:564) ~[na:na]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:197) ~[spring-web-5.3.6.jar:5.3.6]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:141) ~[spring-web-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:894) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:808) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1060) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:962) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:626) ~[tomcat-embed-core-9.0.45.jar:4.0.FR]
    at org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883) ~[spring-webmvc-5.3.6.jar:5.3.6]
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:733) ~[tomcat-embed-core-9.0.45.jar:4.0.FR]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:227) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53) ~[tomcat-embed-websocket-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.3.6.jar:5.3.6]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.3.6.jar:5.3.6]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.3.6.jar:5.3.6]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.3.6.jar:5.3.6]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.3.6.jar:5.3.6]
    at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.3.6.jar:5.3.6]
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:189) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:162) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:143) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:357) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:374) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:893) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1707) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1130) ~[na:na]
    at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:630) ~[na:na]
    at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.45.jar:9.0.45]
    at java.base/java.lang.Thread.run(Thread.java:832) ~[na:na]
1
@Enumerated可能会有所帮助。 - dan1st
1
^---会帮助并解决这个问题。原因是数据库返回一个字符串，而JPA不知道该怎么处理它。@Enumerated告诉JPA“找到枚举并将此字符串转换为该类型”。 - Randy Casburn
1
请注意，Spring与您的问题完全无关；您需要一个JPA的答案，特别是Hibernate（因为这种支持有所不同）。Spring的唯一作用是自动为您启动Hibernate。 - chrylis -cautiouslyoptimistic-
我还不能点赞评论，所以谢谢大家的回答。 - Gathris
1个回答
16

你需要在枚举字段上添加@Enumerated注解。

@Enumerated(EnumType.STRING)
@Column(name="resourceType")
private ResourceType type;

还需要注意以下几点：

1. 在名称字段上添加@Column注释。

@Column(name="name")
private String name;
  1. 对 ResourceType 类进行了改进:
public enum ResourceType {
    FINANCIAL,RAW,FACTORY,LAB
}
3
请注意，枚举常量应该是 UPPER_CASE，但我不确定在数据库中是否能正常工作。 - dan1st
我是否还需要将 ResourceType 中的字符串更改为大写字母？ - Gathris
1
是的，它们需要被更改。 - aang13
1
@dan1st 大写字母是要求还是惯例？好奇想要提高。 - Gathris
2
这是一个命名约定（枚举常量终究是常量）。 - dan1st
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