有没有一种方法可以执行即发即弃的AJAX请求？

Question

I'm working on a web app. When the program switches channel, it sends a "close" AJAX request to the server with the old channel. As the server responses, the app just sends an "open" request to the server to open a new channel. Most of times, this close-wait-done-open-wait-done round runs fast enough, but in case of a special channel, close takes longer than 5 secs, which is unacceptable.

I've set a short timeout for these channels' "close" requests, and it returns, but the new "open" request hangs until the server responses the old "close" request, so timeout just pushed the problem away.

I've set up a setTimeout() for the long close, so as my program calls the "close", it will be delayed, and the new "open" performs before it, but it's also just tossing the problem, when setTimeout() hits in, there will be a long request "in the background", which eats up the browser's ajax request pool, and with some luck, causes pseudo-ajax-hanging at a random AJAX request.

The app has no interest in the result of the "close" request, so it can be dropped, even if it fails.

What's the best practice to perform such fire-and-forget AJAX requests?

(I'm using Chromium browser on Linux, but the app should run on Firefox, too.)

Answer 1

You can use servlet 3.0 Async feature. You can commit the response immediately for your close request and start new thread to do further server processing. You can refer below link for more information on the same. http://www.javaworld.com/article/2077995/java-concurrency/asynchronous-processing-support-in-servlet-3-0.html