This week I was working a lot on our new PLDI submission, which we just submitted (more about that later). During this work I came around an interesting subtlety with respect to delegates and Design By Contract (DBC) . We wanted to validate the fulfillment of a contract for the Iterator interface: When using an iterator i you are only allowed to call i.next() if before that you have checked whether i.hasNext() holds. For PLDI we developed a static analysis approach (using tracematches) that allows you to flag potential violations of this contract. Here is one that we found in Jython, a Python implementation for the Java Virtual Machine and part of the DaCapo benchmark suite:
Prof. Dr. Eric Bodden
Professor for Secure Software Engineering at Heinz Nixdorf Institute, Paderborn University and
Director for Software Engineering and IT Security at Fraunhofer IEM
Director for Software Engineering and IT Security at Fraunhofer IEM
