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AJAX is a client-side, user-interface technology that depends on a server-side component to provide business and data-access logic. Struts 2 makes an excellent backend to AJAX applications, especially when an application uses both AJAX and conventional requests. The elegant and extensible Struts 2 architecture makes it easy to tailor how different types of requests are processed. http://cwiki.apache.org/confluence/pages/createpage.action?spaceKey=WW&fromPageId=13945#
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There are at least three ways to use AJAX with Struts 2.
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The X in AJAX stands for XML, but, in practice, many other formats are used to transfer data between the AJAX frontend and server backend. Aside from XML, other popular formats are JSON (JavaScript Object Notation), plain text, and HTML snippets.
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