Scala Map considered a PersistentEntity causing NullPointerException in UriToEntityConverter [DATAREST-857]

Abhijit Sarkar opened DATAREST-857 and commented

I'm converting a pet project from Java to Scala. It uses the following frameworks:

• Spring Boot
• Spring HATEOAS
• Spring Data Rest
• Spring Data MongoDB
• Embedded MongoDB

I hit a wall with that at startup. org.springframework.data.rest.core.UriToEntityConverter constructor tries to look up an entry previous stored in field persistentEntities of class org.springframework.data.mapping.context.AbstractMappingContext with key as follows:

org.springframework.data.util.ParameterizedTypeInformation
--- resolvedType: scala.collection.immutable.Map
--- typeArguments: java.lang.String,java.lang.String

UriToEntityConverter loses the type info and just looks up by raw type scala.collection.immutable.Map, thus not finding the entry. It then, without checking for null, does a hasIdProperty and blows up in pieces.

The code is available here on branch feign-scala-boot. The integration test FeignSpecP1 is the one that fails.

Stacktrace:

Caused by: org.springframework.beans.BeanInstantiationException: Failed to instantiate [org.springframework.format.support.DefaultFormattingConversionService]: Factory method 'defaultConversionService' threw exception; nested exception is java.lang.NullPointerException
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:189)
	at org.springframework.beans.factory.support.ConstructorResolver.instantiateUsingFactoryMethod(ConstructorResolver.java:588)
	... 107 more
Caused by: java.lang.NullPointerException
	at org.springframework.data.rest.core.UriToEntityConverter.<init>(UriToEntityConverter.java:68)
	at org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration.uriToEntityConverter(RepositoryRestMvcConfiguration.java:593)
	at org.springframework.data.rest.webmvc.config.RepositoryRestMvcConfiguration.defaultConversionService(RepositoryRestMvcConfiguration.java:209)
	at org.springframework.boot.autoconfigure.data.rest.SpringBootRepositoryRestMvcConfiguration$$EnhancerBySpringCGLIB$$c2974a83.CGLIB$defaultConversionService$51(<generated>)
	at org.springframework.boot.autoconfigure.data.rest.SpringBootRepositoryRestMvcConfiguration$$EnhancerBySpringCGLIB$$c2974a83$$FastClassBySpringCGLIB$$334e15b3.invoke(<generated>)
	at org.springframework.cglib.proxy.MethodProxy.invokeSuper(MethodProxy.java:228)
	at org.springframework.context.annotation.ConfigurationClassEnhancer$BeanMethodInterceptor.intercept(ConfigurationClassEnhancer.java:356)
	at org.springframework.boot.autoconfigure.data.rest.SpringBootRepositoryRestMvcConfiguration$$EnhancerBySpringCGLIB$$c2974a83.defaultConversionService(<generated>)
	at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
	at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
	at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
	at java.lang.reflect.Method.invoke(Method.java:497)
	at org.springframework.beans.factory.support.SimpleInstantiationStrategy.instantiate(SimpleInstantiationStrategy.java:162)
	... 108 more

Affects: 2.4.4 (Gosling SR4)