src/main/java/com/simpligility/maven/plugins/android/phase09package/AarMojo.java
protected File createAarClassesJar() throws MojoExecutionException
    {
        final File obfuscatedJarFile = new File( obfuscatedJar );
        if ( obfuscatedJarFile.exists() )
        {
            attachJar( obfuscatedJarFile );
            return obfuscatedJarFile;
        }

        final File classesJar = new File( targetDirectory, finalName + ".aar.classes.jar" );
        try
        {
            JarArchiver jarArchiver = new JarArchiver();
            jarArchiver.setDestFile( classesJar );
            jarArchiver.addDirectory( projectOutputDirectory,
                    classesJarIncludes,
                    classesJarExcludes );
            jarArchiver.createArchive();
            attachJar( classesJar );
            return classesJar;
        }
        catch ( ArchiverException e )
        {
            throw new MojoExecutionException( "ArchiverException while creating ." + classesJar + " file.", e );
        }
        catch ( IOException e )
        {
            throw new MojoExecutionException( "IOException while creating ." + classesJar + " file.", e );
        }

    }
protected File createAarClassesJar() throws MojoExecutionException
    {
        final File obfuscatedJarFile = new File( obfuscatedJar );
        if ( obfuscatedJarFile.exists() )
        {
            attachJar( obfuscatedJarFile );
            return obfuscatedJarFile;
        }

        final File classesJar = new File( targetDirectory, finalName + ".aar.classes.jar" );
        try
        {
            JarArchiver jarArchiver = new JarArchiver();
            jarArchiver.setDestFile( classesJar );
            jarArchiver.addDirectory( projectOutputDirectory,
                    classesJarIncludes,
                    classesJarExcludes );
            jarArchiver.createArchive();
            attachJar( classesJar );
            return classesJar;
        }
        catch ( ArchiverException e )
        {
            throw new MojoExecutionException( "ArchiverException while creating ." + classesJar + " file.", e );
        }
        catch ( IOException e )
        {
            throw new MojoExecutionException( "IOException while creating ." + classesJar + " file.", e );
        }

    }
Creates an appropriate aar/classes.jar that does not include R

@return File which is the AAR classes jar.
@throws MojoExecutionException