In this article, which was originally published on InfoQ Japan, Daisuke Maki describes some of the challenges of developing responsive AJAX applications, and presents Concurrent.Thread as a solution to easing the complexity involved in asynchronous communcation in AJAX.
From the article:
While increasingly more websites are fully or partially based on AJAX, it is still difficult to develop complicated AJAX applications. What is the main issue which causes this difficulty in developing AJAX applications? Is it asynchronous communication with the server, or is it GUI programming? Both are routinely performed by desktop window applications -- so why is development of AJAX applications which do the same things particularly difficult?
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Let me talk about Concurrent.Thread, a library that allows JavaScript to use multiple threads, since this greatly eases the difficulty associated with asynchronous communication in the AJAX development mentioned above. This is a free-software library implemented in JavaScript, available under the Mozilla Public License / GNU General Public License. You can download the source code from the website.
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With Concurrent.Thread, it is possible to switch execution context from one thread to another as needed even if you write a long and continuous program. Let me briefly talk about how this behavior is achieved. In short, code conversion is used. Very roughly speaking, the function passed to the create() method is first converted to a character string, which is then rewritten so that it can be executed on a piecemeal basis. Then, the rewritten function is executed little by little on the scheduler. The scheduler is responsible for coordinating multiple threads. In other words, it makes adjustments so that each of the rewritten functions will be evenly executed. Concurrent.Thread actually does not create new threads but simply simulates a multi-threaded environment on the original single thread.
Read the full article here.