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Parallel Execution of Tests

The ParallelTest class provides an easy way to run tests in parallel locally, as well as remotely in a test grid.

To enable parallel execution of tests, usually during test development, you need to extend ParallelTest instead of TestBenchTestCase. ParallelTest will automatically:

  • Grab a screenshot if the test fails

  • Terminate the driver after the test ends (remove any calls to WebDriver.quit() you might have in your test)

  • Take any @RunLocally or @RunOnHub annotations on the test class, and the corresponding system properties, into account

For a parallel test, you must define the hub it should be run on (using @RunOnHub or -Dcom.vaadin.testbench.Parameters.hubHostname=[hubHost]) or that it should run locally on a given browser (using @RunLocally or -Dcom.vaadin.testbench.Parameters.runLocally=[browser]-[version]). The system property contains either a browserName, which should (case insensitively) match an enum in com.vaadin.testbench.parallel.Browser or a name-version combination. It can for example be edge or chrome-45.

Local Parallel Execution

When you add a @RunLocally annotation on the test class or define the -Dcom.vaadin.testbench.Parameters.runLocally=[browser]-[version] system property, the ParallelTest will be run using a local browser regardless of any @RunOnHub definition.

public class MyTest extends ParallelTest {
It’s usually better to use the system property to avoid accidentally committing a @RunLocally annotation to the repository.

When you run the tests, TestBench launches multiple browser windows to run each test in parallel.

The default browser to run locally on is Firefox. You can give another browser as a parameter for the annotation, e.g.


For Chrome and IE, you need to have the browser driver installed, as described in "Installing Browser Drivers".

Multi-Browser Execution in a Grid

To run tests in multiple different browsers or remotely, you first need to set up and launch a grid hub and one or more grid nodes, as described in "Running Tests in a Distributed Environment". This enables remote execution in a test grid, although you can run the hub and a test node also in your development workstation.

To run a test case class in a grid, you simply need to annotate the test case classes with the @RunOnHub annotation or using -Dcom.vaadin.testbench.Parameters.hubHostname=[hubHost]). Both the annotation and the system parameter takes the host address of the hub as a parameter. You need to define the browsers to run on in a method annotated with @BrowserConfiguration. It must return a list of DesiredCapabilities.

public class MyTest extends ParallelTest {

   public List<DesiredCapabilities> getBrowserConfiguration() {
       List<DesiredCapabilities> browsers =
           new ArrayList<DesiredCapabilities>();

       // Add all the browsers you want to test

       return browsers;

The actual browsers tested depends on the browser capabilities of the test node or nodes.

If you have more test classes, you can put the configuration in a common base class that extends ParallelTest.