リポジトリーから関係タイプ・オブジェクトを取得するには、RAMSession.getAllRelationshipTypes() または RAMSession.getRelationshipType(String name) を使用します。
//Fetch all relationship types
RAMRelationshipType[] relationshipTypes = session.getAllRelationshipTypes();
//Fetch a relationship type by name
RAMRelationshipType relationshipType = session.getRelationshipType("myRelType");
//Fetch a relationship type by Display Name
relationshipType = session.getRelationshipType("My Relationship Type");