Returning a list of projection from a custom JpaRepository method with Spring Data Rest [DATAREST-1237]

Mahsum Demir opened DATAREST-1237 and commented

Hi,

When Spring Data Rest exposes a custom JpaRepository method with the return type of List<Projection>, GET requests to that method fails with the exception of 

java.lang.IllegalArgumentException: Couldn't find PersistentEntity for type class com.sun.proxy.$Proxy117!
    at org.springframework.data.mapping.context.PersistentEntities.lambda$getRequiredPersistentEntity$2(PersistentEntities.java:78) ~[spring-data-commons-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at java.util.Optional.orElseThrow(Optional.java:290) ~[na:1.8.0_161]
    at org.springframework.data.mapping.context.PersistentEntities.getRequiredPersistentEntity(PersistentEntities.java:77) ~[spring-data-commons-2.0.6.RELEASE.jar:2.0.6.RELEASE]
    at org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler.wrap(PersistentEntityResourceAssembler.java:72) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at org.springframework.data.rest.webmvc.PersistentEntityResourceAssembler.toResource(PersistentEntityResourceAssembler.java:55) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at org.springframework.data.rest.webmvc.AbstractRepositoryRestController.entitiesToResources(AbstractRepositoryRestController.java:110) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at org.springframework.data.rest.webmvc.AbstractRepositoryRestController.toResources(AbstractRepositoryRestController.java:80) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at org.springframework.data.rest.webmvc.RepositorySearchController.lambda$toResource$1(RepositorySearchController.java:209) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at java.util.Optional.map(Optional.java:215) ~[na:1.8.0_161]
    at org.springframework.data.rest.webmvc.RepositorySearchController.toResource(RepositorySearchController.java:206) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at org.springframework.data.rest.webmvc.RepositorySearchController.executeSearch(RepositorySearchController.java:190) ~[spring-data-rest-webmvc-3.0.6.RELEASE.jar:3.0.6.RELEASE]
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_161]
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_161]
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_161]
    at java.lang.reflect.Method.invoke(Method.java:498) ~[na:1.8.0_161]
    at org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:209) ~[spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:136) ~[spring-web-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:102) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:877) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]
    at org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:783) ~[spring-webmvc-5.0.5.RELEASE.jar:5.0.5.RELEASE]

I have created an example project at https://github.com/mahsumdemir/projection-demo.

How to reproduce error?

1. mvn spring-boot:run
2. Go to http://localhost:8080/persons/search/findByNameContains?name=i

Best Regards

10 votes, 10 watchers