NPE on shutdown, regular thread pool

David,
Can you verify if this is the same issue you are seeing with graceful shutdown on windows?

thanks
Jan

Jan,

This is not the same issue with graceful shutdown on windows..

David

Chris,

I used your JettyInvokerNew.java and found out there were compilation errors. "org.mortbay.thread.concurrent.ThreadPool" does not exist.
Anyway so I edited it but still I could not replicate your error.

What webapps were deployed when you started the server?
Before you stopped the server, did you access the deployed webapps on your browser?

David

David,

org.mortbay.thread.concurrent.ThreadPool should only have been referenced in the import statement. I wonder if the fact that it was on the classpath makes any difference?

There were two webapps deployed: "root", which just contains a redirect to the "admin" webapp. There's nothing unusual in either. When the app starts, I open a browser to http://localhost:8080, which hits the root and then redirects. I then call stop() within a jsp page in the admin webapp.

Let me see if I can create a minimal test case in a minimal environment.

Chris

Waiting for the test case or the test webapp that u tested that against ... for it to be replicated.

Simple test case added. To duplicate the issue, create this directory:

/temp/test/webapps/test

Copy index.jsp into it (attached)

Then run main() in JettyInvokerX.java (attached). You should see:

2007-08-10 16:06:47.269::INFO: Logging to STDERR via org.mortbay.log.StdErrLog
2007-08-10 16:06:47.300::INFO: jetty-6.1.5
2007-08-10 16:06:48.675::INFO: Started SelectChannelConnector@0.0.0.0:8080

in the console.

Open up a browser. Navigate to http://localhost:8080/test. Click "stop the server". The stack trace above should get dumped to the console.

The error occurs with both Firefox 1.5 and the most recent version of IE, so it's probably not a browser issue.

Hi Chris,

Since you are also calling the server.stop from a thread coming from its own Threadpool, the call should be asynchronous.

First, configure your server to have a graceful shutdown:
server.setGracefulShutdown(3000); // 3 seconds

And on your stop() method, it should be called asynchronously so that the current running Thread(http request) will be returned to the ThreadPool before the server stops.

Take a look at the snippet below: (It has been tested)

static public void stop() throws Exception{
Thread thread = new Thread()
{
public void run()
{
try

catch(Exception e)

}
};
thread.setDaemon(true);
thread.start();

//if (server != null)

}

not a bug.
This is why Jetty has a graceful shutdown feature .

Thanks. This makes sense. The proposed solution is not ideal, though, because:

1) It sets up a potential race condition

2) It doesn't throw any exceptions to the calling process, where they can be logged

3) It makes stopping the server non-deterministic, so you can't just press a button and then get feedback that the server has stopped.

I think we'll need something a little more complicated. I'll work on it.