前端： 
$.ajax({ 
type:get, 
async: false,//是否异步 
url:http://ip:端口/servlet地址, 
datatype: jsonp, 
contenttype: application/x-www-form-urlencoded;charset=utf-8, 
jsonpcallback: callback, 
data: { }, //传递的参数 
success: function(e){ 
  var r = $.parsejson(e);//e：返回值 
}, 
error: function(xmlhttprequest, textstatus, errorthrown) {} 
}); 
后台：用servlet做的样例 
string callback = request.getparameter(callback);//回调函数 
request.setcharacterencoding(utf-8);//防止中文乱码 
response.setcharacterencoding(utf-8);//防止中文乱码 
//response.setheader(pragma, no-cache); 
//response.setheader(cache-control, no-cache); 
//list要返回的结果 
jsonarray jsonarray = jsonarray.fromobject(list); 
response.getwriter().print(callback+('+jsonarray+'));  
response.getwriter().flush();