public static String autoDetectPackageName(File file) {
try {
Set<String> packageNames = new HashSet<String>();
JarFile jarFile = new JarFile(file);
Enumeration<JarEntry> entries = jarFile.entries();
while (entries.hasMoreElements()) {
JarEntry entry = entries.nextElement();
String name = entry.getName();
if (name.endsWith(".class")) {
logger.debug("Considering package of entry '{}'", name);