Non-blocking IO Question

[Daniel Mikusa <dm...@gopivotal.com>]

I have a question on usage with non-blocking IO.  I'm setting up a ReadListener which implements onDataAvailable like this...

            @Override
            public void onDataAvailable() throws IOException
            {
                while (input.isReady())
                {
                    int read = input.read(buffer);
                    // do something with data...
                }
                // if we're done reading, close up
                if (input.isFinished())
                {
                    complete = true;
                    asyncContext.complete();
                }
            }

This seems to be working, but I'm getting the following NullPointerException.

SEVERE: Exception while processing an asynchronous request
java.lang.NullPointerException
	at org.apache.catalina.connector.CoyoteAdapter.asyncDispatch(CoyoteAdapter.java:389)
	at org.apache.coyote.http11.AbstractHttp11Processor.asyncDispatch(AbstractHttp11Processor.java:1618)
	at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:631)
	at org.apache.coyote.http11.Http11NioProtocol$Http11ConnectionHandler.process(Http11NioProtocol.java:223)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1597)
	at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.run(NioEndpoint.java:1555)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
	at java.lang.Thread.run(Thread.java:744)

After debugging a bit, here is what seems to be happening…

1.) Tomcat calls "onDataAvailable".
2.) The method above runs and reads all of the data.  Because all the data is processed, it comples the context.
3.) Tomcat now tries to call "onAllDataRead", but I think because I've closed the context it fails.

For reference, here's the section of code from CoyoteAdapter where the NPE is generated.

                        Thread.currentThread().setContextClassLoader(newCL);
                        req.getReadListener().onDataAvailable();
                        if (request.isFinished()) {
                            req.getReadListener().onAllDataRead();  // <-- NPE thrown here
                        }

My question here, is my code wrong to call asyncContext.complete() like this?  If I restructure it to wait for "onAllDataRead" and complete the context from there then everything works OK.

Thanks

Dan
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