Difference between reverse ajax and normal ajax
Reverse Ajax: Essentially a concept: the ability to send data from the server to the client. In a standard HTTP Ajax request, data is sent from the client to the server.
Other closely related terms are HTTP poll, long poll, comet, server push, websockets in HTML5.
Comet is a web application model where a request is sent to the server and persists for a long time until a timeout or server event occurs. When the request is complete, another long-lived Ajax request is sent to wait for other server events. With Comet, web servers can send data to a client without an explicit request.
Here is a sample demo I shared on github to show reverse ajax using async function for servlet 3.0 https://github.com/uravik21/ReverseAjax-JspTagJspFragment
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