Jooq fetchInto class java.util.LinkedHashMap cannot be cast to class - kotlin

Question

Giving the last example given in this SO thread.
I get this error:
java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class com.example.dtos.UserElement (java.util.LinkedHashMap is in module java.base of loader 'bootstrap'; com.example.dtos.UserElement is in unnamed module of loader 'app')
Am I supposed to use a special mapper that jooq will be happy with?
Any help is welcome
Edit:
Jooq version: 3.14.3
Postgres: 11
ctx.select(
USERS.ID.`as`("id"),
USERS.USERNAME.`as`("name"),
field(select(jsonArrayAgg(
jsonObject(
jsonEntry("id", USER_ELEMENT.ID),
jsonEntry("name", USER_ELEMENT.ELEMENTS)
)
)
).from(USER_ELEMENT).where(USER_ELEMENT.ID
.`in`(
select(USER_ELEMENT_ACTION.USER_ELEMENT_ID)
.from(USER_ELEMENT_ACTION)
.where(USER_ELEMENT_ACTION.USER_ID.eq(USERS.ID))
)
)).`as`("elements")
).from(USERS)
.apply { if (condition != null) where(condition) }
.fetchInto(UserRoles::class.java)
dto
data class UserRoles(val id: Int, val name: String, val elements: List<UserElement>?)
data class UserElement(val id: Int, val name: String)
I've also tried to use SimpleFlatMapper
ctx.configuration().set(JooqMapperFactory.newInstance().newRecordMapperProvider())
but get
MapperBuildingException: Could not find Getter for JooqFieldKey{field="elements", index=2} returning type
I'm using spring boot and here are my jackson dependencies:
implementation("com.fasterxml.jackson.module:jackson-module-kotlin:2.10.5")
implementation("com.fasterxml.jackson.core:jackson-databind:2.10.0")
Stacktrace:
java.lang.ClassCastException: class java.util.LinkedHashMap cannot be cast to class com.example.dtos.UserElement (java.util.LinkedHashMap is in module java.base of loader 'bootstrap'; com.example.common.dtos.UserElement is in unnamed module of loader 'app')
at com.example.dao.UserDao.findUserAuthorities(UserDao.kt:103) ~[main/:na]
at com.example.service.auth.AuthService.getUserDetailByUsername(AuthService.kt:34) ~[main/:na]
at com.example.security.AuthUserDetailService.loadUserByUsername(WebSecurityConfigurer.kt:58) ~[main/:na]
at com.example.security.jwt.JwtRequestFilter.passAuthToTheSecurityContext(JwtRequestFilter.kt:48) ~[main/:na]
at com.example.security.jwt.JwtRequestFilter.doFilterInternal(JwtRequestFilter.kt:35) ~[main/:na]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.authentication.logout.LogoutFilter.doFilter(LogoutFilter.java:116) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.header.HeaderWriterFilter.doHeadersAfter(HeaderWriterFilter.java:92) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.header.HeaderWriterFilter.doFilterInternal(HeaderWriterFilter.java:77) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.context.SecurityContextPersistenceFilter.doFilter(SecurityContextPersistenceFilter.java:105) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.context.request.async.WebAsyncManagerIntegrationFilter.doFilterInternal(WebAsyncManagerIntegrationFilter.java:56) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.security.web.FilterChainProxy$VirtualFilterChain.doFilter(FilterChainProxy.java:334) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilterInternal(FilterChainProxy.java:215) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.security.web.FilterChainProxy.doFilter(FilterChainProxy.java:178) ~[spring-security-web-5.3.5.RELEASE.jar:5.3.5.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.invokeDelegate(DelegatingFilterProxy.java:358) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.web.filter.DelegatingFilterProxy.doFilter(DelegatingFilterProxy.java:271) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.springframework.web.filter.RequestContextFilter.doFilterInternal(RequestContextFilter.java:100) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.springframework.web.filter.FormContentFilter.doFilterInternal(FormContentFilter.java:93) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.springframework.boot.actuate.metrics.web.servlet.WebMvcMetricsFilter.doFilterInternal(WebMvcMetricsFilter.java:93) ~[spring-boot-actuator-2.3.5.RELEASE.jar:2.3.5.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.springframework.web.filter.CharacterEncodingFilter.doFilterInternal(CharacterEncodingFilter.java:201) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.springframework.web.filter.OncePerRequestFilter.doFilter(OncePerRequestFilter.java:119) ~[spring-web-5.2.10.RELEASE.jar:5.2.10.RELEASE]
at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:202) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:97) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:542) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:143) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:92) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:78) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:343) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:374) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:65) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1590) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128) ~[na:na]
at java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628) ~[na:na]
at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61) ~[tomcat-embed-core-9.0.39.jar:9.0.39]
at java.base/java.lang.Thread.run(Thread.java:834) ~[na:na]

Answer 1

jOOQ 3.14 added support for mapping JSON to arbitrary classes via gson or Jackson out of the box. This is documented here:
https://www.jooq.org/doc/latest/manual/sql-execution/fetching/converter-provider
Notice this is a per-column data type conversion feature, which is invoked by jOOQ's DefaultConverterProvider, not a RecordMapper feature. After more discussions, this appears to be a bug in the RecordMapper, which doesn't provide Jackson with as much generic type information as would be possible in your case:
https://github.com/jOOQ/jOOQ/issues/11008
https://github.com/jOOQ/jOOQ/issues/11213
The bug has been fixed in jOOQ 3.15.0 and 3.14.10