主要是加了个@RequestParam(value = "titles[]")

红色部分为重点

Controller

    @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;  
        }  

jsp页面

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;  
    }});