[hibernate-issues] [Hibernate-JIRA] Commented: (HSEARCH-1106) Compile error on MappingModelMetadataProvider on some JVMs only

Compile error on MappingModelMetadataProvider on some JVMs only --------------------------------------------------------------- Key: HSEARCH-1106 URL: https://hibernate.onjira.com/browse/HSEARCH-1106 Project: Hibernate Search Issue Type: Bug Reporter: Sanne Grinovero Assignee: Gail Badner Priority: Critical On some JVMs compiling Search results in a compile error: {quote} Compilation failure: [ERROR] \hibernate-search\hibernate-search-engine\src\main\java\org\hibernate\search\impl\MappingModelMetadataProvider.java:[251,34] type parameters of <T>T cannot be determined; no unique maximal instance exists for type variable T with upper bounds T,java.lang.annotation.Annotation [ERROR] \hibernate-search\hibernate-search-engine\src\main\java\org\hibernate\search\impl\MappingModelMetadataProvider.java:[257,84] type parameters of <T>T cannot be determined; no unique maximal instance exists for type variable T with upper bounds T,java.lang.annotation.Annotation {quote} See also thread on mailing list: http://lists.jboss.org/pipermail/hibernate-dev/2012-April/008195.html specifically Nicolas: {quote} After a goo bisect it seems 31b485c1aaabd9b0ff178505067147e5628e3010 is the first bad commit. It is HSEARCH-1084 Annotation proxies created by Programmatic Mapping I m still on windows 7 x64 with 1.6.0_24 jvm {quote} and Emmanuel: {quote} It seems that we are a bit optimistic with out generic Russian dolls http://stackoverflow.com/questions/2431334/java-generics-what-is-the-comp... /** * Creates the proxy for an annotation using Hibernate Commons Annotations * @param annotation the AnnotationDescriptor * @return the proxy */ private static <T extends Annotation> T createAnnotation(AnnotationDescriptor annotation) { //This is a filthy workaround for the Annotations proxy generation, //which is using the ContextClassLoader to define the proxy classes //(not working fine in modular environments when Search is used by //other services such as CapeDwarf). //See HSEARCH-1084 //use annotation's own classloader try { return AnnotationFactory.create( annotation, annotation.type().getClassLoader() ); } catch ( Exception e ) { //first try, but we have another trick } //Use TCCL return org.hibernate.annotations.common.annotationfactory.AnnotationFactory.create( annotation ); } Basically the compiler cannot guarantee that T in the outer method is the same as T in the AnnotationFactory.create methods. Unfortunately it yells in some strange language. It looks like the compiler is a bit more stupid on Windows for some obscure reason. Could you try 1.6.0_31 (the latest)? {quote} Assigning to Gail as she was able to reproduce locally and seems to have a solution already.