Running junit tests in parallel in a Maven build?

Question

I'm using JUnit 4.4 and Maven and I have a large number of long-running integration tests.

When it comes to parallelizing test suites there are a few solutions that allow me to run each test method in a single test-class in parallel. But all of these require that I change the tests in one way or another.

I really think it would be a much cleaner solution to run X different test classes in X threads in parallel. I have hundreds of tests so I don't really care about threading individual test-classes.

Is there any way to do this?

Answer 1

Use maven plugin:

<build>     <plugins>     <plugin>         <groupId>org.apache.maven.plugins</groupId>         <artifactId>maven-surefire-plugin</artifactId>         <version>2.7.1</version>         <configuration>             <parallel>classes</parallel>             <threadCount>5</threadCount>         </configuration>     </plugin>     </plugins> </build> 

Answer 2

From junit 4.7 it's now possible to run tests in parallel without using TestNG. Actually it has been possible since 4.6, but there are a number of fixes being made in 4.7 that will make it a viable option. You may also run parallel tests with spring, which you can read about here