How does Maven handle JNI? Is it also a build system for C/C++, or do packages with native bindings require manual build steps?

I googled a bit and found this snippet:

            <plugin>
                <artifactId>exec-maven-plugin</artifactId>
                <version>3.5.1</version>
                <groupId>org.codehaus.mojo</groupId>
                <executions>
                    <execution>
                        <id>Generate-shared-lib</id>
                        <phase>package</phase>
                        <goals>
                            <goal>exec</goal>
                        </goals>
                        <configuration>
                            <executable>bash</executable>
                            <arguments>
                                <argument>generate-lib.sh</argument>
                            </arguments>
                            <environmentVariables>
                                <JAVA_HOME>${env.JAVA_HOME}</JAVA_HOME>
                            </environmentVariables>
                        </configuration>
                    </execution>
                </executions>
            </plugin>