import java.util.Enumeration;
import java.util.zip.ZipEntry;
import java.util.zip.ZipFile;

import static org.gradle.internal.FileUtils.hasExtension;

public class JarFilePackageLister {
    public void listJarPackages(File jarFile, JarFilePackageListener listener) {
        if (jarFile == null) {
            throw new IllegalArgumentException("jarFile is null!");
        }

            it.putNextEntry(new ZipEntry("com/D.class"))
            it.putNextEntry(new ZipEntry("E.class"))
        }
    }

    def testListenerReceiving() {
        when:
        lister.listJarPackages(zipFile, listener)

        then:
        3 * listener.receivePackage("com/a/b/c/")
        2 * listener.receivePackage("com/a/b/")
        2 * listener.receivePackage("com/")
        1 * listener.receivePackage("")

     *
     * @param libraryJar Jar file to add to the index.
     */
    public void addLibraryJar(final File libraryJar) {
        new JarFilePackageLister().listJarPackages(libraryJar, new JarFilePackageListener() {
            @Override
            public void receivePackage(String packageName) {
                Set<File> jarFiles = packageJarFilesMappings.get(packageName);