FlexUnit + Ant

I have been planning this blog for some time, but was spurred on by a recent blog on Continous Integration in Flex. This blog concentrates on integration between Ant and FlexUnit, I will post a follow-up entry with details on how to setup a CruiseControl server for Continuous Integration.

This blog entry was written against Flex 2.0 Beta 3.

I have seen various postings about integration between FlexUnit with Ant, however most solutions seem to require a Flex server. My motivation here was to create an Ant task that has no dependency on a server. That would allow unit tests to be run in autonomously.

Very early on I decided if I was running the tests from Ant I wanted to re-use the JUnit tasks that already ship with Ant. In particular I wanted to use the JUnitReport task, which merges the XML files generated by the JUnit task to produce an HTML report. Therefore I wanted FlexUnit to print the results in the same XML format as the XML formatter used by the JUnit task.

The question was then how to make the XML test results available to the Ant tasks, my answer was to use XML sockets.

Technical Design

My solution is comprised of a controlling Ant task, flexunit, and a FlexUnit test runner, JUnitTestRunner, which is shown in the diagram below. The flexunit task starts a socket server running inside of a thread and launches the Flash Player, which runs the tests using the JUnitTestRunner. When JUnitTestRunner has finished running the test it formats the results as per the JUnit XML format and sends them to the flexunit task over an XML Socket, the flexunit task then saves them to disk. We can then use the JUnitReport task to create a report or use CruiseControl to create a report.


  • Download the Ant distribution.
  • Download the example project (FlexUnitExample).

Software Installation

  • Extract the Ant distribution.
  • Add <your_ant_directory>\bin to your path.
  • Extract the FlexUnitExample project to your Eclipse/FB workspace (you only need to extract it into your workspace if you want to load the project into Eclipse/FB – select File > Import and follow the Existing Projects into Workspace wizard).
  • Edit <your_FlexUnitExample_directory>\build.properties and change the value of the flex.sdk.home property to the location of your Flex2 SDK installation (remember to use forward slashes).
  • The SWF containing your tests must run in the local trusted sandbox, copy FlexUnitExample.cfg from <your_FlexUnitExample_directory> to C:\Documents and Settings\<your_username>\Application Data\Macromedia\Flash Player\#Security\FlashPlayerTrust.
  • Edit FlexUnitExample.cfg so it has the path to <your_FlexUnitExample_directory>\bin.


To run the build script open a command prompt and change directory to <your_FlexUnitExample_directory>. To run the build script execute the following command: ant.

This will execute the Ant build script, which will run the SWF containing the tests and generate a JUnitReport report. The reports directory under <your_FlexUnitExample_directory> will contain the XML files created by JUnitTestRunner, you can view the report by opening <your_FlexUnitExample_directory>\reports\html\index.html. You should see two tests, one that passed and the other that failed.


You can download the source code for flexunit and JUnitTestRunner below, they are provided as an Eclipse Java Project and an Eclipse Flex Library project respectively.

  • Download the source for the flexunit Ant task (FlexAntTasks).
  • Download the source for the JUnitTestRunner (FlexUnitOptional).

You can import these projects into your workspace – extract the files into your workspace and in Eclipse select File > Import and follow the Existing Projects into Workspace wizard.