Category Archives: Java

Java, Performance

iJUG-Magazin Java aktuell – High Performance Java

Java Aktuell Cover Issue 2/2020
Java aktuell 2/2020

After our presentation at the JUG Saxony Day in 2019, we have been asked to turn the talk into an article for the iJUG-Magazin Java aktuell. The February 2020 issue just got published and features this article. So get yourself the latest Java Aktuell or, if you just want to check out the article, use this link to the PDF and enjoy. The article is in German.

The days where Java was considered a slow bytecode interpreter have ended a long time ago. JVM is using many tricks in order to execute a code efficiently and to transform and optimize a Java code on the used hardware. With some knowledge about these processes, you can avoid working against the JVM system, while achieving more speed. Even if you are not chasing every last microsecond, it is still interesting to see what methods and techniques JVM uses for a better understanding of the runtime environment.

Comments are very welcome.

Interesting Reading, Java, Software Development

Java Training Sessions

Today we are going to publish four of our Java training sessions so you can use the material and benefit from it.

Let’s get started with four direct links to extensive material that might help you to understand Java or code quality better or just help you to reflect on topics you already know.

  • The Java Memory Model: Why you have to know the JMM to understand Java and write stable, correct, and fast code.
  • Java Memory Management: Know more about the size of objects and how Java does garbage collection.
  • High Performance Java: All about the smart Java internals that turn your code into fast code and how you can leverage that knowledge.
  • High Quality Code: The anatomy of high quality code that supports longevity, cross-team usage, and correctness. This is not just about Java, this is about good code in general.

Show a little patience when loading the training, these are all large reveal.js based slide sets. Use the arrow keys or space to navigate. Because the slide sets are designed to be interactive sessions, in many cases, not the entire slide context is revealed at once but block by block.

We publish these training sessions because they are also based on openly shared material, it greatly helped us to advance and understand, as well of course advertise a little what Xceptance might be able to do for you.

We will release more of our material in the next weeks and month, so everybody can browse and learn. This won’t be limited to Java and also cover material about approaching load testing, how to come up with test cases, and more about the modern web and its quality and performance challenges. Of course there will be more Java material too. You can get a glimpse of it when you just follow this link and page through the slides: The Infinite Java Training. Please remember, not all material is complete yet.

If you like the material and you need an audio track aka a real presentation, please talk to us. If you see other training needs in the area of quality assurance, testing, and Java, please contact to us.

More to come.

Automation, Java, Open Source, Testing

Neodymium – An Open Source Framework for Web Testing

TL;DR: Neodymium is a Java-based test library for web automation that utilizes existing libraries (Selenide, WebDriver, Allure, JUnit, Maven) and concepts (localization, test multiplication, page objects) and adds missing components such as test data handling, starter templates, multi-device handling, and other small but useful everyday helpers.

Motivation

As a company focused on quality assurance and testing, Xceptance always needs test automation software, especially end-to-end automation software. Several years ago we built a Firefox add-on that was designed to create and run browser automation. The tool was primarily used by people who didn’t necessarily have a strong background in software development. Today, the landscape is a bit different: Mozilla cut the cord on the APIs we were using and standard programming languages have largely taken over test automation because they are more flexible and less proprietary. These changes convinced us it was time to implement an idea we had already hatched, namely our own Open Source test automation project: Neodymium. It is written in and utilizes the Java platform, it is MIT licensed, and of course you will find it on GitHub: https://github.com/Xceptance/neodymium-library

Basis

There are many libraries out there to aid web automation in Java, so developers are faced with the task of choosing ones they like and somehow making them work together. On top of that, there are tasks that require some custom code to work properly. We identified the overall tooling problem mostly as a hurdle in getting started and setting up a project. Finally, there are always things missing such as test data handling, concurrency, and common patterns which you don’t want to have to develop yourself. We chose JUnit, Selenide, WebDriver, Maven, and Allure for the base tooling.

Selenide provides an easy-to-use API to control Selenium WebDriver. Allure offers good mechanics to generate useful reports based on the assertions and actions you perform throughout your test cases. Maven is used to set up the build and execution environment for our framework and all the test projects. We decided to use JUnit as the test runner since it is the de facto standard in the Java world, but we enhanced the capabilities of JUnit to do even more. At its heart, Neodymium is a JUnit runner that wraps default JUnit behavior and adds significant useful functionality to it.

Multiple Browsers

You want to be able to run the same tests for different resolutions and/or browsers to simulate the browsers most common among your users. Additionally, you need to be able to implement small differences within your test execution to address variants such as responsive designs or progressive web apps. So we added a way to run web browsers with different configurations and retrieve the current device type and resolution from within the test.

Neodymium provides a Java annotation that can be added to your test case, in order to run different browser setups. Neodymium is very flexible in configuring browsers, allowing you to fully leverage the Chrome device emulation offerings.

Test Data

Another common task is the execution of a test case with different data sets, such as testing address forms with all the relevant variations. The basic idea is to have test data and data sets in structured files next to your code, preferably as JSON, XML, property style, or simply CSV. Hence, we introduced an easy-to-use API to access the current data set and retrieve basic types from it. Furthermore, you can configure specific scenarios running only a subset or even no data set at all by adding proper annotations. To complete the picture, Neodymium supports test data on a global and package-level scope.

Localization

Another recurring topic in modern software projects is localization. Most of the web sites that are in need of test automation also support several locales. We decided to provide an out-of-the-box solution.

Neodymium’s localization feature makes use of a central translation file written in YAML format. YAML helps to structure the translations. Additionally, we implemented a simple way to override specific translations for different locales. The localized text can be easily retrieved using Neodymium API methods that are globally available.

Development Support

As it is essential to understand what your test is doing, we added a feature that enables you to slow down the test execution and highlight elements that match the current selector. Since you can chain selectors using Selenide, any chain of elements is also represented by the highlighting. With this feature activated, a developer can track down the cause of test failures much more easily. In addition, we provide information on how to set up logging in your project should you need that. Finally, we decided to use the Page Object pattern to organize the website-related code to reduce the maintenance effort and increase reusability.   

Reporting

Allure is a widely used framework to generate reports. When using Neodymium with Selenide, your automation code also contributes report information. Your test classes and methods are listed as well as detailed Selenide automation commands. In case of errors, additional details such as screenshots and source code of the page in question are available. Neodymium also provides means to structure code blocks for reporting purposes.

Continuous Integration

Implementing principles of continuous integration will deliver more reliable software by increasing efficiency, and automation is nothing without a continuous integration environment.  Yet in almost every development cycle you will eventually end up needing varied settings due to differences in your setup, which can get complicated. Neodymium provides support for extra configuration files during development to override the standard production settings as needed. Furthermore, the framework supports overriding properties that change the configuration of your test execution by setting environment variables or simply passing Java arguments.

Because automation is supposed to run quickly, Neodymium provides support for parallel test execution and also demonstrates that setup as part of the sample test suite.

Documentation and Templates

Does Neodymium address some of your test automation challenges? Does it sound like a good entry point for your test automation?

Neodymium is hosted on GitHub (https://github.com/Xceptance/neodymium-library), where the accompanying project wiki (https://github.com/Xceptance/neodymium-library/wiki) provides extensive documentation to help you get started and answer your questions.

You might also want to take a look at the comprehensive example projects using Neodymium with Cucumber (https://github.com/Xceptance/neodymium-cucumber-example) or plain Java (https://github.com/Xceptance/neodymium-example). We’ve even provided a template project (https://github.com/Xceptance/neodymium-template) to get you started automating in no time.

License

Neodymium is licensed under the MIT License.

Who Are We

We are Xceptance. A software testing company with strong commerce knowledge and projects with customers from all around the world. Besides Neodymium, we have developed Xceptance Load Test (XLT), a load and performance test tool that is available free of charge and features an extensive range of awesome features to make the tester’s and developer’s life easier.

If you are looking for test automation that also covers the performance side of life, take a look at XLT. You can write and run load tests with real browsers including access to data from the Web Performance Timing API. In case browsers are too heavy, XLT has other modes of load testing to offer as well.

We offer professional support for Neodymium as well as implementation and training services.

Automation, Java, Software Development, Testing, XLT

Use XLT with Sauce Labs and BrowserStack

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Sauce Labs and BrowserStack – What Are They and Why Use Them?

This approach still work fine, but we came up with a much better one. Head over to GitHub and see our Multi-Browser-TestSuite for XLT. It will make multi browser testing a breeze. By the way, all the code is licensed under the MIT license, so absolute flexibility for you.

Sauce Labs and BrowserStack allow you to run automated test cases on different browsers and operating systems. Both provide more than 200 mobile and desktop browsers on different operating systems. The benefit? You can focus on coding instead of having to maintain different devices. You can easily run your test cases written on iOS on an Internet Explorer without actually buying a Windows device; and last not least, you don’t need to worry about drivers or maintenance.

By the way, Internet Explorer even seems to run faster at Sauce Labs than on a desktop machine. Also note that Sauce Labs supports Maven builds.
Continue reading Use XLT with Sauce Labs and BrowserStack →

Automation, Java, Testing

Simplify Your Life With a Little UI Automation

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Are you familiar with someone asking you to do things such as putting all of your clients into the new CRM or inserting 80 new users in a software product x? If so and if your software has no import feature, you probably found yourself copying and pasting all day long. A simple way to save you from this torture is using a UI automation tool like Sikuli Script.

What is Sikuli?

Sikuli automates UI functionalities like mouse, keyboard, and clipboard actions. It works with UI recognition to identify UI components such as buttons, input fields, or menus. To use this kind of recognition, Sikuli compares the actual screen with screenshots from the user.
Continue reading Simplify Your Life With a Little UI Automation →

Automation, Java, Testing, XLT

Web Drivers in XLT: Basic Access Authentication

Today’s article of our WebDrivers series deals with HTTP authentication – a topic that, at first sight, seems to be very specific and of minor relevance. However, in the world of software testing it’s way more important than you’d think.

HTTP Authentification IE
HTTP Authentication IE
Often you will have an additional testing instance of a website to be tested. These instances are protected from abuse which is why they require credentials before you can access them. See below for an example in Internet Explorer:

This browser dialog appears just once. If you’ve entered the right credentials, you can access the related website as often as you like without further authentication – as long as you don’t reopen the browser. The latter is a critical issue for automated WebDriver testing.
Continue reading Web Drivers in XLT: Basic Access Authentication →

Automation, Java, Testing, XLT

Handle authentication during WebDriver testing

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Sometimes authentication is necessary before a test case can be executed. While HtmlUnit based tests can easily enter and confirm authentication requests, most browser based tests, cannot workaround the dialog. This is a browser security measure to prevent automated data capture and/or data entering. WebDriver for Firefox delivers a solution for that problem, but IE and Chrome rely on a manual interaction with the browser before the test automation can run.

The following steps describe a solution for the authentication problem and how to run a script test case as WebDriver based test. The key to this solution is the usage of Sikuli, an image based testing tool that directly interacts with the screen to find the right elements by using the screen.
Continue reading Handle authentication during WebDriver testing →

Java, Testing, XLT

Review Of Cross-Browser Testing Tools

Smashing Magazine lists a couple of free and commercial tools to cover cross-browser testing:

Good news: very powerful free testing tools are available for Web designers today. Some are more user-friendly than others, and some have significantly better user interfaces. Don’t expect much (if any) support with these tools. But if you’d rather not spend extra money on testing, some great options are here as well.

Read the full article…

By the way, our own tool Xceptance LoadTest (XLT) offers a way to run cross-browser functional tests. XLT leverages WebDriver, a multi-browser API for automation. WebDriver does not support all browser and does not equally support all browser well, but we tried to iron out as much as possible. On top of it, you can use the XLT Script Developer to easily create automation scripts and run them either using our own scripting language or export them to Java to directly run them on the WebDriver-API.

You can download Xceptance LoadTest for free with no strings attached from our web site: www.xceptance-loadtest.com.

Java, Software Development

Spurious wakeup – the rare event

After hunting for quite some time for a strange application behavior, I finally found the reason.

The Problem

The Java application was behaving strangely in 4 out of 10 runs. It did not process all data available and assumed that the data input already ended. The application features several producer-consumer patterns, where one thread offers preprocessed data to the next one, passing it into a buffer where the next thread reads it from.

The consumer or producer fall into a wait state in case no data is available or the buffer is full. In case of a state change, the active threads notifies all waiting threads about the new data or the fact that all data is consumed.

On 2-core and 8-core machines, the application was running fine but when we moved it to 24-cores, it suddenly started to act in an unpredictable manner.
Continue reading Spurious wakeup – the rare event →