How to get coverage on code which is in a different module than tests? - maven

Question

I have a project with three modules api, impl and report. Report module is just for coverage report aggregation. Impl module contains tests for both api and impl modules. I managed to get coverage working correctly, when I have tests in their respective modules, but this is not possible in my project, since the tests are not module specific. Is it possible to get combined code coverage even in this case with proper configuration or is it just impossible?
|- pom.xml (root)
|
|-- api-module
|--- src
|---- main
|
|-- impl-module
|--- src
|---- main
|---- test
|--- pom.xml
|
|-- report-module
|---pom.xml
pom.xml (root)
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>${jacoco.version}</version>
<executions>
<execution>
<id>initialize-coverage-before-unit-test-execution</id>
<goals>
<goal>prepare-agent</goal>
</goals>
<configuration>
<exclClassLoaders>*QuarkusClassLoader</exclClassLoaders>
<destFile>${project.build.directory}/jacoco-quarkus.exec</destFile>
<append>true</append>
</configuration>
</execution>
</executions>
<configuration>
<excludes>
<exclude>**/model/*DTO.*</exclude>
</excludes>
</configuration>
</plugin>
<plugin>
<artifactId>maven-surefire-plugin</artifactId>
<version>${surefire-plugin.version}</version>
<configuration>
<systemPropertyVariables>
<java.util.logging.manager>org.jboss.logmanager.LogManager</java.util.logging.manager>
<maven.home>${maven.home}</maven.home>
</systemPropertyVariables>
</configuration>
</plugin>
pom.xml (api-module)
<build>
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>${jacoco.plugin.version}</version>
<executions>
<execution>
<id>generate-code-coverage-report</id>
<phase>test</phase>
<goals>
<goal>report</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
pom.xml (impl-module)
<build>
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>${jacoco.plugin.version}</version>
<executions>
<execution>
<id>generate-code-coverage-report</id>
<phase>test</phase>
<goals>
<goal>report</goal>
</goals>
</execution>
</executions>
</plugin>
</plugins>
</build>
pom.xml (report-module)
<dependencies>
<dependency>
<groupId>com.example</groupId>
<artifactId>module-api</artifactId>
<version>${project.version}</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>com.example</groupId>
<artifactId>module-impl</artifactId>
<version>${project.version}</version>
<scope>compile</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.jacoco</groupId>
<artifactId>jacoco-maven-plugin</artifactId>
<version>${jacoco.plugin.version}</version>
<executions>
<execution>
<id>report-aggregate</id>
<phase>verify</phase>
<goals>
<goal>report-aggregate</goal>
</goals>
</execution>
<execution>
<id>merge-results-data</id>
<phase>verify</phase>
<goals>
<goal>merge</goal>
</goals>
<configuration>
<fileSets>
<fileSet>
<directory>${project.build.directory}</directory>
<includes>
<include>jacoco-quarkus.exec</include>
</includes>
</fileSet>
</fileSets>
</configuration>
</execution>
</executions>
</plugin>
</plugins>
</build>