code: private void extractApkClassesJar( Artifact artifact ) throws MojoExecutionException
      {
          final File apkClassesJar = getUnpackedLibHelper().getJarFileForApk( artifact );
          final File unpackedClassesJar = getUnpackedLibHelper().getUnpackedClassesJar( artifact );
          try
          {
              FileUtils.copyFile( apkClassesJar, unpackedClassesJar );
          }
          catch ( IOException e )
          {
              throw new MojoExecutionException(
                      "Could not copy APK classes jar " + apkClassesJar + " to " + unpackedClassesJar, e );
          }
          getLog().debug( "Copied APK classes jar into compile classpath : " + unpackedClassesJar );
  
      }
docs: Copies a dependent APK jar over the top of the placeholder created for it in AarMavenLifeCycleParticipant.
  <p>
  This is necessary because we need the classes of the APK added to the compile classpath.
  NB APK dependencies are uncommon as they should really only be used in a project that tests an apk.
  
  @param artifact APK dependency for this project whose classes will be copied over.