Aspect] is a simple and practical aspect-oriented extension to Java With just a few new constructs, AspectJ provides support for modular implementation of a range of crosscutting concerns. In AspectJ's dynamic join point model, join points are well-defined points in the execution of the program; pointcuts are collections of join points; advice are special method-like constructs that can be attached to pointcuts; and aspects are modular units of crosscutting implementation, comprising pointcuts, advice, and ordinary Java member declarations. AspectJ code is compiled into standard Java bytecode. Simple extensions to existing Java development environments make it possible to browse the crosscutting structure of aspects in the same kind of way as one browses the inheritance structure of classes. Several examples show that AspectJ is powerful, and that programs written using it are easy to understand.

An overview of AspectJ

The Environmental Protection Agency (EPA) provides access to information on a variety of topics related to the environment and strives to inform citizens of health risks. The EPA also has an extensive library network that consists of 26 libraries throughout the United States, which provide access to a plethora of information to EPA employees, scientists, and researchers. The EPA implemented a reorganization project to digitize their materials so they would be more accessible to a wider range of users, but this plan was drastically accelerated when the EPA was threatened with a budget cut. It chose to close and reduce the hours and services of some of their libraries. As a result, the agency was accused of denying users the “right to know” by making information unavailable, not providing an adequate strategic plan, and discarding vital materials. This case study explores the background of the digitization project, the practices implemented, and the critiques of the project.

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The Environmental Protection Agency

In the past five years there has been a dramatic increase in work on Search-Based Software Engineering (SBSE), an approach to Software Engineering (SE) in which Search-Based Optimization (SBO) algorithms are used to address problems in SE. SBSE has been applied to problems throughout the SE lifecycle, from requirements and project planning to maintenance and reengineering. The approach is attractive because it offers a suite of adaptive automated and semiautomated solutions in situations typified by large complex problem spaces with multiple competing and conflicting objectives.This article1 provides a review and classification of literature on SBSE. The work identifies research trends and relationships between the techniques applied and the applications to which they have been applied and highlights gaps in the literature and avenues for further research.

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Search-based software engineering: Trends, techniques and applications

In accordance with embodiments, there are provided mechanisms and methods for allowing access to developed applications via a multi-tenant on-demand database service, in a controlled environment. These mechanisms and methods for providing such access can enable embodiments to provide additional control over the development process as well as the access of such developed applications. The ability of embodiments to provide such additional control may lead to an improved application development framework, etc.

Method and system for allowing access to developed applications via a multi-tenant on-demand database service

Regression testing is a crucial part of software development. It checks that software changes do not break existing functionality. An important assumption of regression testing is that test outcomes are deterministic: an unmodified test is expected to either always pass or always fail for the same code under test. Unfortunately, in practice, some tests often called flaky tests—have non-deterministic outcomes. Such tests undermine the regression testing as they make it difficult to rely on test results. We present the first extensive study of flaky tests. We study in detail a total of 201 commits that likely fix flaky tests in 51 open-source projects. We classify the most common root causes of flaky tests, identify approaches that could manifest flaky behavior, and describe common strategies that developers use to fix flaky tests. We believe that our insights and implications can help guide future research on the important topic of (avoiding) flaky tests.

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An empirical analysis of flaky tests

In this paper, we present a verification methodology that integrates formal verification techniques with verification by simulation, thereby providing means for generating simulation test suites that ensure coverage. We derive the test suites by means of BDD-based symbolic techniques for describing and traversing the implementation state space. In our approach, we provide a high-level of control over the generated test suites; a powerful abstraction mechanism directs the generation procedure to specific areas, that are the focus for verification, thereby withstanding the state explosion problem. The abstraction is achieved by partitioning the implementation state variables into categories of interest. We also depart from the traditional graph-algorithmic model for conformance testing; instead, using temporal logic assertions, we can generate a test suite where the set of state sequences (paths) satisfies some temporal properties as well as guaranteeing transition coverage. Our methodology has been successfully applied to the generation of test suites for IBM PowerPC and AS/400 systems.

Coverage-Directed Test Generation Using Symbolic Techniques

In this paper we demonstrate a method for generation of assembler test programs that systematically probe the architecture of a PowerPC superscalar processor. We show innovations such as ways to make small models for large designs, predict, with cycle accuracy the movement of instructions through the pipes (taking into account stalls and dependencies) and generation of test programs such that each reaches a new architectural state. We compare our method to the established practice of massive random generation and show that the quality of our tests, as measured by transition coverage, is much higher. The main contribution of this paper is not in theory as the theory has been discussed in previous papers, but in describing how to translate this theory into practice in a practical way a task that was far from trivial.

Micro architecture coverage directed generation of test programs

A method for race detection in parallel software, including performing an execution of software under test (SUT), the SUT having an expected outcome. The method further includes detecting a race condition in the SUT responsive to a first interleaving generated during the execution, replaying the first interleaving to a start-point of the race condition, and imposing a second interleaving at the start-point of the race condition. The method also includes determining a second-execution outcome of the SUT responsive to the second interleaving, and comparing the expected outcome with the second-execution outcome.

Race detection for parallel software

A computer-implemented method and system for graphically displaying at least two edges extending between common points in a graphical structure. A particular implementation relates to the display of execution paths of a computer program component having multiple execution paths so as to allow proper differentiation between the execution paths. The computer program component is processed so as to derive a data structure containing nodes representing all basic blocks thereof, edges representing lines connecting the nodes, and execution paths traversed during operation of the computer program, component. The resulting data structure is displayed graphically in 3-D. In order to allow the execution paths to be distinguished when they pass along the same edge of the graph, different sections of the edge are color coded. This can be done by spatially separating the edges and coloring each edge uniquely; or by dividing each edge into different colored sections in respect of each execution path. Alternatively, there can be superimposed on each edge one or markers each corresponding to a different execution path and each having a unique color.

Method and system for presenting data structures graphically

A test coverage tool provides output that identifies differences between the actual coverage provided by a test suite run on a program under test and the coverage criteria (e.g., the coverage criteria required by the test/development team management). The output from the test coverage tool is generated in the same language that was used to write the coverage criteria that are input to an automated test generator to create the test cases which form the test suite. As a result, the output from the coverage tool can be input back into the automated test generator to cause the generator to revise the test cases to correct the inadequacies. This allows iterative refinement of the test suite automatically, enabling automated test generation to be more effectively and efficiently used with more complex software and more complex test generation inputs. In preferred embodiments, test coverage analysis results of several different test suites, some manually generated and others automatically generated, are used to produce a streamlined automatically-generated test suite and/or to add missing elements to an automatically generated test-suite.

Shmuel Ur

Papers

Coverage-Directed Test Generation Using Symbolic Techniques

Micro architecture coverage directed generation of test programs

Race detection for parallel software

Method and system for presenting data structures graphically

Method and system for integrating test coverage measurements with model based test generation