DRL compilation error on a generic type property ------------------------------------------------ Key: DROOLS-1724 URL: https://issues.jboss.org/browse/DROOLS-1724 Project: Drools Issue Type: Bug Affects Versions: 6.5.0.Final Environment: drools 6.5.0.Final / java 1.8.0_131 Reporter: Ryo Murai Assignee: Mario Fusco Fix For: 7.3.1.Final I got a DRL compilation error on accessing through a generic type property. Minimized object definition is below. {code:borderStyle=solid} public interface OrderLine<T extends Product> { T getProduct(); } public interface Product { String getId(); String getCategory(); } // and I have concrete classes, ex. Book, BookOrderLine<Book>, DVD, DVDOrderLine<DVD>, ... etc {code} DRL(snippet) is here {code:borderStyle=solid} when $orderLine: OrderLine() // compilation failed Product( id == $orderLine.product.id || category == $orderLine.product.category ) from discountProducts {code} This causes below exception. {panel} java.lang.RuntimeException: [Message [id=1, kieBase=defaultKieBase, level=ERROR, path=rules/checkorder-not-compiled.drl, line=15, column=0 text=Unable to Analyse Expression id == $orderLine.product.id || category == $orderLine.product.category: [Error: unable to resolve method using strict-mode: java.lang.Object.category()] [Near : {... Line.product.id || category == $orderLine.product.category ....}] ^ [Line: 15, Column: 2]]] {panel} This is weird because it won't occur when the restriction has single condition like below. Drools could analyze this expression. {code:borderStyle=solid} when $orderLine: OrderLine() // this is compiled, even if `Product(id == $orderLine.product.id)` Product( category == $orderLine.product.category ) from discountProducts {code}