Using different testing providers

Tests in your tes source directory can be any combination of the following:

• TestNG
• JUnit
• POJO

Which providers are available is controlled simply by the inclusion of the appropriate dependencies (ie, junit:junit for JUnit, org.testng:testng 4.7+ for TestNG). Since this is required to compile the test classes anyway, no additional configuration is required.

Note that any normal Surefire integration works identically no matter which providers are in use - so you can still produce a Cobertura report and a Surefire results report on your project web site for your TestNG tests, for example.

The POJO provider above allows you to write tests that do not depend on JUnit. They behave in the same way, running all test* methods that are public in the class, but the API dependency is not required. To perform assertions, the JDK 1.4 assert keyword can be used, or you can use org.apache.maven.surefire.assertion.Assert.

All of the providers support the following configuration. However, there are additional options available if you are running TestNG tests (including if you are using TestNG to execute your JUnit tests, which occurs by default if both are present in Surefire).

See TestNG Configuration for more information.

Skipping Tests

To skip running the tests for a particular project, you configure the skip parameter:

<project>
  ...
  <build>
    ...
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-surefire-plugin</artifactId>
      <configuration>
        <skip>true</skip>
      </configuration>
    </plugin>
    ...
  </build>
  ...
</project>

Alternatively, you can execute the following on the command line to skip tests:

mvn -Dmaven.test.skip=true install

Using System Properties

To add a System property, use the following configuration:

<project>
  ...
  <build>
    ...
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-surefire-plugin</artifactId>
      <configuration>
        <systemProperties>
          <property>
            <name>propertyName</name>
            <value>propertyValue</value>
          </property>
        </systemProperties>
      </configuration>
    </plugin>
    ...
  </build>
  ...
</project>

Forking

If you need to run your tests in a new JVM process you can use the forkMode option to start a new JVM process once for all your tests, or start a new JVM process for each of your tests. You can also set any arbitrary options like -enableassertions or any other JVM options. Here's an example of what this might look like:

<project>
  ...
  <build>
    ...
    <plugin>
      <groupId>org.apache.maven.plugins</groupId>
      <artifactId>maven-surefire-plugin</artifactId>
      <configuration>
        <forkMode>pertest</forkMode>
        <argLine>-enableassertions</argLine>
      </configuration>
    </plugin>
    ...
  </build>
  ...
</project>

Note: You do not need to manually enable assertions if you are using them in your unit tests - Surefire enables them on your test classes automatically under JDK 1.4+.

The default setting is once. It can also be set to never to run in process for a small performance improvement.

Class Loading Issues

By default, Surefire loads classes using the default Java mechanism. However, it can be set to use "child first" classloading, like a web application - meaning your dependencies take precedence over those in the JDK. If you find this is necessary, you can do so by setting the childDelegation flag to true:

<project>
  ...
  <build>
    ...

    <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <configuration>
          <childDelegation>true</childDelegation>
        </configuration>       

      </plugin>
  ...
  </build>
  ...
</project>

Tests Inclusion and Exclusion

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <configuration>
          <includes>
            <include>Sample.java</include>
          </includes>
        </configuration>
      </plugin>
    </plugins>
  </build>
  ...
</project>

<project>
  ...
  <build>
    <plugins>
      <plugin>
        <groupId>org.apache.maven.plugins</groupId>
        <artifactId>maven-surefire-plugin</artifactId>
        <configuration>
          <excludes>
            <exclude>**/TestCircle.java</exclude>
            <exclude>**/TestSquare.java</exclude>
          </excludes>
        </configuration>
      </plugin>
    </plugins>
  </build>
  ...
</project>

Running a single test

During development, you may run a single test class repeatedly. To run this through Maven, you must use the test parameter. For example:

mvn -Dtest=TestCircle test

There are other parameters that you can configure like testFailureIgnore, reportsDirectory, and so on. For full documentation, click here.