Mehdi Bagherzadeh

• Professor (Assistant) at Oakland University

Efficiency is essential to support responsiveness w.r.t. ever-growing datasets, especially for Deep Learning (DL) systems. DL frameworks have traditionally embraced deferred execution-style DL code -- supporting symbolic, graph-based Deep Neural Network (DNN) computation. While scalable, such development tends to produce code that is error-prone, n...

Efficiency is essential to support responsiveness w.r.t. ever-growing datasets, especially for Deep Learning (DL) systems. DL frameworks have traditionally embraced deferred execution-style DL code that supports symbolic, graph-based Deep Neural Network (DNN) computation. While scalable, such development tends to produce DL code that is error-prone...

Logging is a significant programming practice. Due to the highly transactional nature of modern software applications, massive amount of logs are generated every day, which may overwhelm developers. Logging information overload can be dangerous to software applications. Using log levels, developers can print the useful information while hiding the...

Logging—used for system events and security breaches to describe more informational yet essential aspects of software features—is pervasive. Given the high transactionality of today's software, logging effectiveness can be reduced by information overload. Log levels help alleviate this problem by correlating a priority to logs that can be later fil...

Context: Software developers are increasingly facing the challenges of writing code that is not only concurrent but also correct. Objective: To help these developers, it is necessary to understand concurrency topics they are interested in, their difficulty in finding answers for questions in these topics, their sentiment for these topics, and how t...

Logging -- used for system events and security breaches to more informational yet essential aspects of software features -- is pervasive. Given the high transactionality of today's software, logging effectiveness can be reduced by information overload. Log levels help alleviate this problem by correlating a priority to logs that can be later filter...

Actor concurrency is becoming increasingly important in the development of real-world software systems. Although actor concurrency may be less susceptible to some multithreaded concurrency bugs, such as low-level data races and deadlocks, it comes with its own bugs that may be different. However, the fundamental characteristics of actor concurrency...

Streaming APIs are becoming more pervasive in mainstream Object-Oriented programming languages and platforms. For example, the Stream API introduced in Java 8 allows for functional-like, MapReduce-style operations in processing both finite, e.g., collections, and infinite data structures. However, using this API efficiently involves subtle consider...

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...

Software developers are increasingly required to write big data code. However, they find big data software development challenging. To help these developers it is necessary to understand big data topics that they are interested in and the difficulty of finding answers for questions in these topics. In this work, we conduct a large-scale study on St...

Background Software developers are increasingly required to write concurrent code. However, most developers find concurrent programming difficult. To better help developers, it is imperative to understand their interest and difficulties in terms of concurrency topics they encounter often when writing concurrent code. Aims In this work, we conduct a...

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 correctly and efficiently may involve subtle considerations. In this poster, we present our ongoing work and preliminary results towards an automated refactorin...

Asynchronous message passing concurrency with higher level concurrency constructs including activities, asynchronous method invocations and future return values is gaining increased popularity, as an alternative to shared memory concurrency with lower level threads and locks. However, similar to data races in shared memory concurrency, message race...

Separating crosscutting concerns while preserving modular reasoning is challenging. Type-based interfaces (event types) separate modularized crosscutting concerns (observers) and traditional object-oriented concerns (subjects). Event types paired with event specifications were shown to be effective in enabling modular reasoning about subjects and o...

The need for concurrency in modern software is increasingly fulfilled by utilizing the message passing paradigm because of its modularity and scalability. In the message passing paradigm, concurrently running processes communicate by sending and receiving messages. Asynchronous messaging introduces the possibility of message ordering problems: two...

Pervasive and oblivious interference makes modular reasoning about concurrent programs difficult. This work presents Panini, a concurrent programming model with sparse and cognizant interference that enables modular reasoning.

Modular reasoning about concurrent programs is complicated by the possibility of interferences happening between any two instructions of a task (pervasive interference), and these interferences not giving out any information about the behaviors of potentially interfering concurrent tasks (oblivious interference). Reasoning about a concurrent progra...

Separating crosscutting concerns while preserving modular reasoning is challenging. Type-based interfaces (event types) separate modularized crosscutting concerns (observers) and traditional object-oriented concerns (subjects). Event types paired with event specifications were shown to be effective in enabling modular reasoning about subjects and o...

It is claimed in the literature that the contracts of a system present crosscutting structure during its realization. In this context, there has been attempts to improve separation of crosscutting contracts, e.g. by aspect-oriented programming and design by contract languages, but none give programmers textual separation of contracts/specifications...

Aspect-oriented programming (AOP) is a popular technique for modularizing crosscutting concerns. In this context, researchers have found that the realization of design by contract (DbC) is crosscutting and fares better when modularized by AOP. However, previous efforts aimed at supporting crosscutting contract modularity might actually compromise t...

Aspect-oriented programming (AOP) is a popular technique for modularizing crosscutting concerns. In this context, researchers have found that the realization of design by contract (DbC) is crosscutting and fares better when modularized by AOP. However, previous efforts aimed at supporting crosscutting contract modularity might actually compromise t...

Modular understanding of behaviors and flows of exceptions may help in their better use and handling. Such reasoning tasks about exceptions face unique challenges in event-based implicit invocation (II) languages that allow subjects to implicitly invoke observers, and run the observers in a chain. In this work, we illustrate these challenge in Ptol...

As aspect-oriented (AO) programming techniques become more widely used, their use in critical systems such as aircraft and telephone networks, will become more widespread. However, careful reasoning about AO code seems difficult because: (1) advice may apply in too many places, and (2) standard specification techniques do not limit the control effe...

The Implicit Invocation (II) architectural style improves modularity and is promoted by aspect-oriented (AO) languages and design pat-terns like Observer. However, it makes modular reasoning difficult, especially when reasoning about control effects of the advised code (subject). Our language Ptolemy, which was inspired by II lan-guages, uses trans...

This tutorial will provide an introduction to Ptolemy. Ptolemy is a programming language whose goals are to improve a software engineer's ability to separate conceptual concerns, while preserving encapsulation of object-oriented code and the ability of programmers to modularly reason about their code. In particular, Ptolemy's features are useful to...

Making assertions about the program's control flow is important for reasoning purposes, e.g. ensuring that an advice proceeds to the original join point. Obliviousness of the base modules to the aspects in aspect oriented languages, like AspectJ, makes it difficult to make such assertions in a modular manner. Base-aspect interfaces like crosscuttin...

Several proposals have advocated notion of aspect-oriented (AO) interfaces to solve modular reasoning problems, but have not shown how to specify these interfaces to facilitate modular reasoning. Our work on translucid contracts shows how to specify AO interfaces which allow modular understanding and enforcement of control flow interactions.

In previous work, Rajan and Leavens presented the design of Ptolemy, a language which incorporates the notion of quan-tified, typed events for improved separation of concerns. In this work, we present an empirical study to evaluate the ef-fectiveness of Ptolemy's design by applying it to a series of architectural releases of a software product line...