ajax转递数组，springmvc后端接收

@RequestMapping(value="/exportExcel", method = RequestMethod.POST)
@ResponseBody
public String exportExcel(<span style="color:#FF0000;">@RequestParam(value = "titles[]")</span> String[] titles){
System.out.println(titles);
return null;
}

var param = {titles:['col1','col2','col3']};
$.ajax({url:url, type:"post", data:param, async:false, dataType:"json", cache:false, error:function (data) {
rtnObj = data.responseText;
}, beforeSend:function (XMLHttpRequest) {
//ajaxStart();
}, complete:function (XMLHttpRequest, textStatus) {
//ajaxComplete();
}, success:function (data) {
rtnObj = data;
}});