Unable to specifically catch server startup failures

[io7m]

Hello.

Currently, the listen() method runs asynchronously and if any errors are raised, they're dumped into whatever is the current uncaught exception handler. Unless I'm mistaken, there doesn't seem to be a simple and reliable way to catch "the server failed to start up" errors. I can install an uncaught exception handler, but that'll catch every possible type of exception and I won't be able to tell which of those came from the server.

Case in point:

AsyncHttpServer s = new AsyncHttpServer();
s.listen(99999);  // Will obviously fail

The server will throw an IllegalArgumentException when executed in a Runnable in the background somewhere, which will be treated as an uncaught exception by the Android runtime and the entire program will crash.

What I would really like is to be able to supply a simple callback such as:

interface StartupListener
{
  void onServerStartupSucceeded(AsyncHttpServer s);
  void onServerStartupFailed(Throwable x);
}

... so that I can reliably detect failed startups and notify the user of exactly what went wrong.

Would you accept patches that implemented this? It doesn't seem like it'd be difficult to add.

[rancpine]

I find listen() returns null, then client can't connect to my server until I restart the whole process.