Eötvös Loránd University



Abstracts and materials




L1. Tim Steenvoorden, Rinus Plasmeijer (Radboud University, NL): Visual Prototyping using Task Oriented Programming

In this course we will create applications using a visual assistant for Task Oriented Programming (TOP). TOP is a novel programming paradigm developers can use to quickly prototype multi-user web applications. The central way of modelling applications in TOP is by creating Tasks. Tasks represent pieces of real world work that can be performed by people or by systems. Using a handful of operations, they can be combined into bigger and more powerful Tasks.

We will explore the basic concepts of TOP by studying some example applications, while showing how to model them using Tasks in a visual development environment. The visual environment guides developers during the modelling process. The tool only presents sane ways to create and expand Tasks, and gives hints how to solve type and scoping errors. This results in correct and compilable program code.

Students are encouraged to extend the example applications in a hands on session. Our visual approach does only require basic knowledge on programming and data types. The introduction on TOP and its modelling principles are a prerequisite on the course on mTasks..

L2. Mart Lubbers, Pieter Koopman, Rinus Plasmeijer (Radboud University, NL): Task Oriented Programming for the Internet of Things

The Internet of Things (IoT) consists of devices that sense, act, and communicate with other systems on the internet. Typical requirements for IoT devices are that they must be cheap and consume little energy. This is achieved by driving the IoT devices by small microprocessors with tiny amounts of memory and processing power. Most of these systems have no proper operating system and just run a specific program to execute the intended task.

This makes programming of the IoT very challenging. The single program running on such a device must interleave all subtasks, like monitoring inputs, controlling the peripherals and communication. Various devices that cooperate have to agree on the protocol used and have to solve the notorious concurrent programming problems.

In this lecture we will give a hands-on introduction to Task Oriented Programming (TOP) for the IoT. In our TOP approach the communication between devices and their servers is handled transparently by the mTask system. The entire system is programmed in a single high-level functional program. For each subtask of the system we define a corresponding mTask. These subtasks can be composed by task combinators to more powerful tasks. These tasks can inspect intermediated values of other subtasks as well as communicate with any other task in the system via Shared Data Sources (SDS). Subtasks for an IoT device are dynamically shipped to the device and interpreted there. The strong type system prevents runtime type problems. This TOP approach greatly simplifies the development of software for the IoT.

L3.1 João Paulo Fernandes (Univerity of Coimba, PT), Rui Pereira (University of Minho & University of Beira Interior, PT): Paint your Programs Green - On the Energy Efficiency of Data Structure Implementations

In this lecture we analyse and compare the energy efficiency of different implementations for concrete data abstractions such as Sequences, Sets or Associative Collections. For each implementation, we inspect how operations such as adding, deleting or searching for elements handle different workloads. The subjects of our study are a functional programming language and an object-oriented one. Our goal is to provide developers actionable information that has already been integrated in supporting tools, and that can steer green software construction.

L3.2 João Saraiva (University of Minho, PT): Green Software in an Engineering Course

Sustainable development has become an increasingly important theme not only in the world politics, but also an increasingly central theme for the engineering professions around the world.  Software engineers are no exception as shown in various recent research studies. Despite the intensive research on green software, today’s undergraduate computing education often fails to address our environmental responsibility. We present a module on green software that we introduced as part of an advanced course on software engineering. We introduce a catalogue of energy smells and green refactorings, which our preliminary results show that do help students in reason and optimizing the energy consumption of software systems.

L3.3 Csaba Szabó (Technical University of Kosice, SK): Software Application Energy Profiling for Java Projects

This tutorial addresses the energy efficiency of software applications implemented in Java programming language. The first part describes the current state of the art in energy profiling as well as options for displaying energy consumption of segments of the source code. Next, a custom code analysis method for displaying information is presented addressing the processor, operating memory, and hard disk. After this analysis, a short introduction to the implemented Java application follows. In order to demonstrate the practical use of the application, several test solutions are created, where we measured the energy consumption. With each example, we put emphasis on solving one problem with at least two solutions to determine which implementation has lower energy intensity. The results of the examples are also part of this tutorial.

L4. Štefan Korečko (Technical University of Kosice, SK): Development of Correct Software with B-Method

One of the well-recognized approaches to the development of correct software systems is the utilization of formal methods (FM) for their specification and verification. FM are rigorous mathematically based techniques for the specification, analysis, development and verification of software and hardware. Rigorous means that a formal method provides a formal language with unambiguously defined syntax and semantics and mathematically based means that some mathematical apparatus (formal logic, set theory, etc.) is used to define the language.

One of the FM used in industrial practice is B-Method, a state based, model-oriented formal method intended for software development. B-Method is primarily used in the railway sector, for the safety-critical software behind automated urban metro subway systems (including the one in Budapest). The strength of B-Method lies in a well-defined development process, which allows to specify a software system as a collection of components called B-machines and to refine such an abstract specification to a concrete one. The concrete specification can be automatically translated to ADA, C or another programming language. An internal consistency of the abstract specification and correctness of each refinement step are verified by proving a set of predicates called proof obligations (PObs). The whole development process, including proving, is supported by an industrial-strength software tool called Atelier B.

This tutorial serves as a gentle, practical, introduction to B-Method. During the tutorial, the participants will develop a simple software controller for a railway scenario. They will be able to run the scenario with the controller in a toolset containing corresponding simulation game.

L5. Nikola Domazet (Ericsson Nikola Tesla, HR), Tihana Galinac Grbac (University of Pula, HR): Programming of Advanced Management and Orchestration of Virtualized Network Resources - Selection of Case Studies

New management and orchestration (MANO) functions are standardized for use in distributed and virtualised network environments. Their main role is to provide safe and reliable operation of applications using network functions. Therefore, as continuation of our previous lecture where we provide basic concepts, here in this lecture we will provide a selection of case studies where these functions are implemented and explain the advanced mechanisms behind and simplicity of their application.

L6. Tibor Brunner, Máté Cserép, Anett Fekete, Mónika Mészáros, Zoltán Porkoláb (Eötvös Loránd University, HU): Code Comprehension with Advanced Tool Support

In this tutorial we will introduce the state of the art code comprehension tools to the students. We will give a theoretical foundation for code comprehension, navigation and code visualization methods and approaches to apply them in practical software development. In the practice session we will demonstrate how to set up a specific toolset: CodeCompass with incremental parsing, Visual Studio Code as front-end tool and the usage of the Language Server Protocol. We will parse an open source library and find and fix a specific bug in it using the toolset.

L7. Clemens Grelck (University of Amsterdam, NL): Functional Array Programming with Single Assignment C: Opportunities and Challenges

SAC (Single Assignment C) is in several aspects a functional programming language out of the ordinary. As the name suggests, SAC combines a C-like syntax (with lots of curly brackets) with a state-free, purely functional semantics. Originally motivated to ease adoption by programmers with an imperative background, the choice offers surprising insights into what constitutes a "typical" functional or a "typical" imperative programming language construct. Again on the exotic side for a functional language, SAC emphasises multi-dimensional arrays, instead of lists and trees. Array programming treats multi-dimensional arrays in a holistic way: functions map potentially huge argument arrays to result arrays with a call-by-value semantics, and new array operations are defined by composition of existing ones. SAC is a high-productivity language for application domains that deal with large collections of data in a computationally intensive way.

At the same time SAC also is a high performance language competing with low-level imperative languages through compilation technology. The abstract view on arrays combined with the functional semantics support far-reaching program transformations. A highly optimised runtime system takes care of automatic memory management with a focus on immediate memory reuse. Last not least, the SAC compiler exploits the state-free semantics of SAC and the data-parallel nature of SAC programs for fully compiler-directed acceleration on a large variety of contemporary machine architectures, from multi-core servers to GPGPU accelerators and clusters of workstations.

The lectures motivate the language design of SAC and provide a hands-on introduction to array programming as a paradigm. We look into all aspects from the underlying array calculus to the concrete language design with imperative-looking functional code, discuss a multitude of examples, explore compilation challenges and eventually see some performance results on various parallel computing architectures.

L8. Viktória Zsók, Li Jianhao, Yuri Kim (Eötvös Loránd University, HU): Balanced Distributed Computation Patterns

The state-of-the-art concurrent software development made extensive usage of various methodologies and approaches to obtain high speed up. However, parallelism remains one of the most difficult domains especially in the case of pattern based programming approaches. The main purpose is to explore parallel computation schemes in a new environment, to illustrate the appropriateness and applicability in novel distributed computation setups. The amount of parallelism is explored based on many factors such as: applied computation pattern refined granularity, semantics of distributed nodes, data streaming, and especially load balancing.

L9. JongWon Kim (Gwangju Institute of Science and Technology, KR): Computer Systems for AI-inspired Cloud: Theory & Lab

In this lecture, an overview-style introduction of modern computer systems will be made around the definition, operating system virtualization & containers, cloud-native computing, HPC/HPDA clustering, and cloud data centres. This step-by-step introduction will help the audience to better understand the recent development of computer systems for AI-inspired cloud. Also, co-designed SmartX-mini Labs are introduced to guide how to make hands-on-experience for selected computer system issues.