Well, you need to incorporate exec-maven-plugin, this plug-in performs the same thing that you do on command prompt when you type in java -cp .;jarpaths TestMain. You can pass argument and define which phase (test, package, integration, verify, or deploy), you want this plug-in to call your main class.
You need to add this plug-in under <build> tag and specify parameters. For example
<project>
...
...
<build>
<plugins>
<plugin>
<groupId>org.codehaus.mojo</groupId>
<artifactId>exec-maven-plugin</artifactId>
<version>1.1.1</version>
<executions>
<execution>
<phase>test</phase>
<goals>
<goal>java</goal>
</goals>
<configuration>
<mainClass>my.company.name.packageName.TestMain</mainClass>
<arguments>
<argument>myArg1</argument>
<argument>myArg2</argument>
</arguments>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>
...
...
</project>
Now, if you right-click on on the project folder and do Run As > Maven Test, or Run As > Maven Package or Run As > Maven Install, the test phase will execute and so your Main class.