...
Solr Indexing
The solr indexer uses Fedora's fcr:transform service the LDPath service to convert RDF documents to JSON. A default transformation program can be specified in the service configuration (e.g. default or myTransformation). It is also possible to override the default transformation program by assigning an RDF property to particular documents: <> indexing:hasIndexingTransformation "specialTransform". Furthermore, one can choose to index only certain documents from the repository. By identifying certain documents as <> a indexing:Indexable and enabling the indexable.predicate configuration value, only those resources will be indexed. (For Tomcat/Jetty-deployed applications, this can be enabled by setting JAVA_OPTS="-Dfcrepo.onlyIndexableObjects=true")
...