a web service is created in java ,which will accept Json(f.. k) who the hell created it,request,

i want to send a parameter, and get the resonse from the same,how to send a request to json and get the response from through javascript,

please help me ,i'm facing so many pressure due to this json,

please help
pls tell me any link that help in json java ,j2ee tutorial ,that a beginer can under statand..