问题:

I'm thinking about how limiting it is for AJAX apps to have to poll for updates, when what would be ideal is for javascript to be able to set up a real two way connection to the server. I'm wondering if there is some method of integrating javascript with a browser plugin that can make a tcp connection so that I could pass data into and out of the browser plugin.

回答1:

Here is an implementation with a similar approach:

socketjs

It uses a Java Applet and bridges its API to JavaScript, interesting...

And here another one:

jSocket

This one is a wrapper of the Actionscript 3 Socket API, bridged to JavaScript...

回答2:

WebSockets is designed to solve this problem.

回答3:

You can use node.js framework's socket.io package which can can be installed via npm (A node package manager).

More detailed usage.

回答4:

jSocket and Stream are two options that utilize Flash's built-in XML sockets, though neither appears to be production-ready. I'd lean towards using a Flash-based solution rather than Java, as browser penetration is higher and generally offers a better user experience (load times & stability).