By Guest Blogger Andrew Binstock
JUnit 5 is about to be released and this special issue of Java Magazine tells you what's new and how to use the features added in this release. We start off with an overview of the new features, followed by an article showing how to include JUnit 5 in your build and how to run tests from v4 and v5 together.
For readers who want to know more about the capabilities and how to use more-obscure features, we do a deep dive into this release's architecture, which is substantially different from earlier versions.
We follow this with an interview with Kent Beck, who was the parent of JUnit through its first four releases. He also popularized test-driven development (TDD), and created extreme programming (XP), the set of techniques that evolved into Agile programming. In its original formulation, TDD and strongly promoted the idea that no code should be written without first having written a failing test. As this interview explains, Beck's view on what code requires failing tests or, in fact, any tests at all has evolved significantly.
We finish up our coverage of JUnit with a lengthy article on mutation testing, which is a little-known but highly effective technique. It validates unit tests on projects that require a high level of integrity (that is, truly mission-critical code). Mutation testing goes through the bytecodes of unit tests and runs the tests while making small changes to what they test. Did the changed test fail or throw an exception? If not, is the test exercising the code as you think it is? By assessing these failures, mutation testing reveals incomplete or slightly incorrect tests.
We round out this issue with an editorial on the future of NetBeans now that the IDE will be moving out of Oracle's sponsorship; a demonstration of how to implement the most common design patterns in Java; an explanation of using the cloud for development; and a guide to contributing to JSRs and other Java standards. And, of course, our famous Java quiz.
Remember that you can read the issue online. Or, if you prefer, you can download it in PDF format. For the download option, access the magazine from a laptop or desktop and you'll see the download icon on the right.
You'll also note that you can now access back issues of Java Magazine from this year and last year. We'll eventually make all our back issues available to subscribers. To go to the back issues, click on the topmost icon in the right panel, you'll see a table of contents for the current issue and a list of the back issues from 2015 and 2016. Highlight the one you want to read, then click on the View button at the top of the panel. You can download any of the back issues as a PDF file.