Software Evolution for Machine Learning
Machine Learning (ML), including Deep Learning (DL), systems are pervasive in today’s data-driven society. Such systems are complex; they are comprised of ML models and many subsystems that support learning processes. As with other complex systems, ML systems are prone to classic technical debt issues, especially when such systems are long-lived, but they also exhibit debt specific to these systems. In this project, we study refactorings performed in real-world, open-source software and the technical debt issues they alleviate. Continue reading
An Empirical Study on the Use and Misuse of Java 8 Streams
Introduction Streaming APIs allow for big data processing of native data structures by providing MapReduce-like operations over these structures. However, unlike traditional big data systems, these data structures typically reside in shared memory accessed by multiple cores. Although popular, this emerging hybrid paradigm opens the door to possibly detrimental behavior, such as thread contention and … Continue reading
Safe Automated Refactoring for Intelligent Parallelization of Java 8 Streams
Introduction The Java 8 Stream API sets forth a promising new programming model that incorporates functional-like, MapReduce-style features into a mainstream programming language. However, using streams efficiently may involve subtle considerations. For example, although streams enable developers to run their code in parallel with little alteration, it is often not obvious if such code runs … Continue reading
Automatic Migration of Legacy Java Method Implementations to Interfaces
Java 8 is one of the largest upgrades to the popular language and framework in over a decade. It offers several new, key features that can help make programs easier to read, write, and maintain, especially in regards to collections. These features include Lambda Expressions, the Stream API, and enhanced interfaces, many of which help … Continue reading
Automated Refactoring of Legacy Java Software to Enumerated Types
Introduction Modern Java languages introduce several new features that offer significant improvements over older Java technology. In this project, we consider the new enum construct, which provides language support for enumerated types. Prior to recent Java languages, programmers needed to employ various patterns (e.g., the weak enum pattern) to compensate for the absence of enumerated … Continue reading
Pointcut Change Prediction
Pointcut fragility is a well-documented problem in Aspect-Oriented Programming; changes to the base-code can lead to join points incorrectly falling in or out of the scope of pointcuts. Deciding which pointcuts have broken because of changes made to the base-code is a daunting task, especially in large and complex systems. This project represents an automated … Continue reading
Porting the NetBeans Lambda Expression Refactoring to Eclipse
Introduction Java 8 is one of the largest upgrades to the popular language and framework in over a decade. There are several new key features of Java 8 that can help make programs easier to read, write, and maintain. Java 8 comes with many features, especially related to collection libraries. These include such new features … Continue reading
Pointcut Rejuvenation: Recovering Pointcut Expressions in Evolving Aspect-Oriented Software
Introduction Pointcut fragility is a well-documented problem in Aspect-Oriented Programming; changes to the base-code can lead to join points incorrectly falling in or out of the scope of pointcuts. In this project, we use an automated approach that limits fragility problems by providing mechanical assistance in pointcut maintenance. The approach is based on harnessing arbitrarily … Continue reading
