He Zhang

Nanjing University | NJU · School of Software Engineering

Code review has become a common quality assurance process in modern software development. For large-scale, active software projects emphasizing continuous delivery and fast feedback, one of the main challenges with code review is prioritizing the many Code Review Requests (CRRs) these projects receive. Many heuristic rules and machine learning mode...

Enhancing the modular structure of existing systems has attracted substantial research interest, focusing on two main methods: (1) software modularization and (2) identifying design issues (e.g., smells) as refactoring opportunities. However, re-modularization solutions often require extensive modifications to the original modules, and the design i...

The various performances of a change in code reviews have received growing concerns from software organizations and researchers. Researchers have investigated these aspects in isolation from one another (e.g., predicting the merge approval of a change after review), but this approach provides limited value for decision-making (e.g., decomposing com...

Traceability plays a vital role in facilitating various software development activities by establishing the traces between different types of artifacts (e.g., issues and commits in software repositories). Among the explorations for automated traceability recovery, the IR (Information Retrieval)-based approaches leverage textual similarity to measur...

The electric submersible pump (ESP) is the primary artificial lift method for offshore oil wells. Due to the high operation and maintenance costs, it is crucial to avoid operations and conditions that negatively impact ESP wells' lifespan and seek ways to prolong their run life. However, the lifespan of ESP is affected by many factors, and it isn't...

As code review is a tedious and costly software quality practice, researchers have proposed several machine learning-based methods to automate the process. The primary focus has been on accuracy, that is, how accurately the algorithms are able to detect issues in the code under review. However, human intervention still remains inevitable since resu...

With the increasing application and complexity of Artificial Intelligence (AI) systems, the trustworthiness of AI has garnered widespread attention across various fields. An AI system is a specific type of software system with unique trustworthiness requirements due to its distinctive characteristics in data and algorithms. Our objective is to inve...

Software engineers play a centric role throughout the software development lifecycle. Their activities directly impact the quality, performance, and successful delivery of software products, in particular for enterprises with an emphasis on high levels of quality assurance and timely delivery. Proper incentives that motivate software engineers are...

Software products have many configurations to meet different environments and diverse needs. Building software with multiple software configurations typically incurs high costs in terms of build time and computing resources. Incremental builds could reuse intermediate artifacts if configuration settings affect only a portion of the build artifacts....

Software process simulation (SPS) has become an effective tool for software process management and improvement. However, its adoption in industry is less than what the research community expected due to the burden of measurement cost and the high demand for domain knowledge. The difficulty of extracting appropriate metrics with real data from proce...

Code review is an important practice in software development. One of its main objectives is for the assurance of code quality. For this purpose, the efficacy of code review is subject to the credibility of reviewers, i.e, reviewers who have demonstrated strong evidence of previously making quality-enhancing comments are more credible than those who...

MicroService Architecture (MSA), a predominant architectural style in recent years, still faces the arduous task of identifying the boundaries of microservices. Domain-Driven Design (DDD) is regarded as one of the major design methods for addressing this task in practice, which aims to iteratively build domain models using a series of patterns, pri...

Continuous Integration (CI) enables developers to detect defects early and thus reduce lead time. However, the high frequency and long duration of executing CI have a detrimental effect on this practice. Existing studies have focused on using CI outcome predictors to reduce frequency. Since there is no reported project using predictive CI, it is di...

Software process simulation models (SPSMs) that are based on descriptive process models offer the executability that can demonstrate dynamic changes of software processes over time. Verification and validation (V&V) is critical in SPSMs for guaranteeing the quality and reliability of models. V&V of dynamic software process models is more complex an...

As a predominant design method for microsservices architecture (MSA), domain‐driven design (DDD) utilizes a series of standard patterns in both models and implementations to effectively support the design of architectural elements. However, an implementation may deviate from its original domain model that uses certain patterns. The deviation betwee...

By adopting agile and lean practices, DevOps aims to achieve rapid value delivery by speeding up development and deployment cycles, which however lead to more security concerns that cannot be fully addressed by an isolated security role only in the final stage of development. DevSecOps promotes security as a shared responsibility integrated into th...

The microservice architecture has been commonly adopted by large scale software systems exemplified by a wide range of online services. Service monitoring through anomaly detection and root cause analysis (RCA) is crucial for these microservice systems to provide stable and continued services. However, compared with monolithic systems, software sys...

In software quality management, the selection strategy for proper metrics varies depending on the application scenarios and measurement objectives. MicroService Architecture (MSA), despite being commonly employed nowadays, still cannot be reliably measured and compared if the microservices in a system are independent. Software managers and architec...

Traceability systems are important for solving problems due to the increasing scale of the global supply chain, such as food safety crises and market disorder. Blockchain, as an immutable and decentralized ledger, is able to optimize the traditional traceability system by ensuring the transparency and reliability of the system data. However, the us...

Background: Software Process Simulation (SPS) has become an effective tool for software process management and improvement. However, its adoption in industry is less than what the research community expected due to the burden of measurement cost and the high demand for domain knowledge. The difficulty of extracting appropriate metrics with real dat...

Background Seeking an appropriate architecture for the design of software is always a challenge. Although microservices are claimed to be a lightweight architecture style that can improve current practices with several characteristics, many practices are based on different circumstances and reflect variant effects. Empirical inquiry gives us a syst...

Traceability approves trace links among software artifacts based on whether two artifacts are related by system functionalities. The traces are valuable for software development, but are difficult to obtain manually. To cope with the costly and fallible manual recovery, automated approaches are proposed to recover traces through textual similaritie...

As a recently predominant architecture style, MicroService Architecture (MSA) is likely to suffer the issues of poor maintainability due to inappropriate microservice boundaries. Architectural Smell (AS), as a metaphor for potential architectural issues that may have negative impacts on software maintenance, can be used to pinpoint refactoring oppo...

Context: DevOps and microservices are acknowledged to be important new paradigms to tackle contemporary software demands and provide capabilities for rapid and reliable software development. Industrial reports show that they are quickly adopted together in massive software companies. However, because of the technical and organizational requirements...

Context: DevOps and microservices are acknowledged to be important new paradigms to tackle contemporary software demands and provide capabilities for rapid and reliable software development. Industrial reports show that they are quickly adopted together in massive software companies. However, because of the technical and organizational requirements...

To reinforce the quality of code delivery, especially to improve future coding quality, one global Information and Communication Technology (ICT) enterprise has institutionalized a retrospective style inspection (namely retro-inspection), which is similar to Fagan inspection but differs in terms of stage, participants, etc. This paper reports an in...

Modern code review is a critical and indispensable practice in a pull-request development paradigm that prevails in Open Source Software (OSS) development. Finding a suitable reviewer in projects with massive participants thus becomes an increasingly challenging task. Many reviewer recommendation approaches (recommenders) have been developed to sup...

Background: Logging practices provide the ability to record valuable runtime information of software systems to support operations tasks e.g., service monitoring and troubleshooting. However, current logging practices face common challenges. On the one hand, although the importance of logging practices has been broadly recognized, most of them are...

Continuity and steadiness are vital for services with massive users, which requires the anomalies of services should be detected and resolved in a timely manner. Our previous work proposed a tool, namely ImpAPTr (Impact Analysis based on Pruning Tree) , to identify the combination of multiple dimensional attributes as the clues leading to the roo...

Context Systematic Literature Review (SLR), as a tool of Evidence-Based Software Engineering (EBSE), has been widely used in Software Engineering (SE). However, for certain topics in SE, especially those that are trendy or industry driven, academic literature is generally scarce and consequently Grey Literature (GL) becomes a major source of eviden...

Sentiment analysis on software engineering (SE) texts has been widely used in the SE research, such as evaluating app reviews or analyzing developers sentiments in commit messages. To better support the use of automated sentiment analysis for SE tasks, researchers built an SE-domain-specified sentiment dictionary to further improve the accuracy of...

We are organizing 2nd edition of the international workshop on DevOps Quality Management (Trondheim, Norway, 21-23 June 2021). The workshop proceedings will be integrated in the 24th International Conference on Evaluation and Assessment in Software Engineering (EASE 2021) companion proceedings. EASE is ranked as A software engineering conference....

Nowadays, unloading gas wells with coiled tubing is a common application to the field. However, it still lacks of adequate understanding of dynamic behavior of the unloading process. This paper investigates the process of liquid unloading by gas lift with coiled tubing under transient conditions. This unloading process can be divided into three sta...

Context: Emerging from the agile culture, DevOps particularly emphasizes development and deployment speed to achieve rapid value delivery, which however brings some security risks to the software development process. DevSecOps is an extension of DevOps, which is considered as a means to intertwine development, operation and security. Some companies...

Software development is a collective undertaking, and the team’s efficiency is critical in development. In order to reduce project management overheads and improve productivity, a global information and communication technology enterprise institutionalizes an organization wide small-team practice, called fireteams, to tackle the problems arising fr...

Context: As a rapidly adopted architectural style in software engineering, Microservices Architecture (MSA) advocates implementing small-scale and independently distributed services, rather than binding all functions into one monolith. Although many initiatives have contributed to the quality improvement of microservices-based systems, there is sti...

Context: Quality Assessment (QA) of reviewed literature is paramount to a Systematic Literature Review (SLR) as the quality of conclusions completely depends on the quality of selected literature. A number of researchers in Software Engineering (SE) have developed a variety of QA instruments and also reported their challenges. We previously conduct...

Context: Following on other scientific disciplines, such as health sciences, the use of Grey Literature (GL) has become widespread in Software Engineering (SE) research. Whilst the number of papers incorporating GL in SE is increasing, there is little empirically known about different aspects of the use of GL in SE research. Method: We used a mixe...

The proliferation of DevOps enables significant acceleration and automation of the delivery and deployment of massive software products. Unfortunately, the development of supporting documents that is vital for large‐scale software systems in many cases does not keep pace with the rhythm of feature delivery using DevOps in practice, which becomes th...

Logs are the execution results of logging statements in software systems after being triggered by various events, which is able to capture the dynamic behavior of software systems during runtime and provide important information for software analysis, e.g., issue tracking, performance monitoring, etc. Obviously, to meet this purpose, the quality of...

Software Engineering (SE) community has recently been investing significant amount of effort in qualitative research to study the human and social aspects of SE processes, practices, and technologies. Ethnography is one of the major qualitative research methods, which is based on constructivist paradigm that is different from the hypothetic-deducti...

Microservices architecture emphasizes employing multiple small-scale and independently deployable microservices, rather than encapsulating all function capabilities into one monolith. Correspondingly, microservice-oriented decomposition, which has been identified to be an extremely challenging task, plays a crucial and prerequisite role in developi...

Context: Data synthesis is one of the most significant tasks in Systematic Literature Review (SLR). Software Engineering (SE) researchers have adopted a variety of methods of synthesizing data that originated in other disciplines. One of the qualitative data synthesis methods is meta-ethnography, which is being used in SE SLRs. Objective: We aim at...

Background Handover is common in open source software (OSS) development, which could have a negative impact on software quality and progress. Objective We aim to identify factors associated with the handover process for future improvements. Method We first propose a metric, i.e. Active Days Coverage (abbr. ADC) together with an algorithm, i.e., H...

Nowadays, unloading gas wells with coiled tubing is a common application to the field. However, it still lacks of adequate understanding of dynamic behavior of the unloading process. This paper investigates the process of liquid unloading by gas lift with coiled tubing under transient condition. This unloading process can be divided into three stag...

Synthesizing data extracted from primary studies is an integral component of the methodologies in support of Evidence Based Software Engineering (EBSE) such as System Literature Review (SLR). Since a large and increasing number of studies in Software Engineering (SE) incorporate qualitative data, it is important to systematically review and underst...

Cloud computing has become a compelling paradigm built on compute and storage virtualization technologies. The current virtualization solution in the Cloud widely relies on hypervisor-based technologies. Given the recent booming of the container ecosystem, the container-based virtualization starts receiving more attention for being a promising alte...

Systematic Literature Review (SLR) is becoming a vital part of present day research in software process improvement (SPI). Nevertheless, there is no available study that provides detail review of the published software process improvement SLRs. Objective: The aim of this article is to classify the SLRs of SPI in order to identify the main research...

Background: Cloud Computing is increasingly booming in industry with many competing providers and services. Accordingly, evaluation of commercial Cloud services is necessary. However, the existing evaluation studies are relatively chaotic. There exists tremendous confusion and gap between practices and theory about Cloud services evaluation. Aim: T...

Benchmark suites are significant for evaluating various aspects of Cloud services from a holistic view. However, there is still a gap between using benchmark suites and achieving holistic impression of the evaluated Cloud services. Most Cloud service evaluation work intended to report individual benchmarking results without delivering summary measu...

Background: Spot pricing is considered as a significant supplement for building a full-fledged market economy for the Cloud ecosystem. However, it seems that both providers and consumers are still hesitating to enter the Cloud spot market. The relevant academic community also has conflicting opinions about Cloud spot pricing in terms of revenue gen...

Background: Handling large-sized classes is one of the major challenges in Personal Software Process (PSP) education in a tertiary education environment. We applied a pairing approach in PSP education and managed to mitigate the size challenge without sacrificing education effectiveness, which has been verified in an experiment in 2010 (PSP2010). H...

Verification and Validation (V&V) is a critical step in software process modelling to secure the model's quality and credibility. Software Process Simulation Models (SPSMs) that are based on descriptive process models offer the executability that is able to demonstrate the dynamic changes of software process over time. The V&V of process simulation...

Background: Capture-ReCapture (CRC), as a technique for post-inspection defect estimation, has been studied in Software Engineering (SE) community since 1990s. While most studies focused on the performance evaluation of various CRC models and estimators, few have been done on the assessment of the credibility of estimation results, rendering the di...