in src/main/java/org/apache/sling/testing/email/impl/SmtpServerWrapper.java [76:84]
private int reflectiveGetEffectiveBindPort(SMTPServer server) throws ReflectiveOperationException {
// we control the version of Wiser used so there is no risk of an exception here
Field field = SMTPServer.class.getDeclaredField("serverSocket");
field.setAccessible(true);
ServerSocket socket = (ServerSocket) field.get(server);
return socket.getLocalPort();
}