GWT Atmosphere-comet implemantation getting AtmosphereMappingException: No AtmosphereHandler maps request
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I have to implement comet in GWT and for implementing comet i have use atmosphere library. i have go through all the steps that mention on their website but at the end i am getting AtmosphereMappingException does anyone know what is the problem or any other configuration required ?

i have search lot of about this exception but i didn't get any solution any one can help ? 