json读取json文件,上传到后台

js代码：

$("#saveBtn").on("click",function(){
    var file=$("#secretKeyUpload")[0].files[0];
    var tableId=$("#tableId").val();
    if(tableId!=""){
        var formData=new FormData();
        var url="/site/site/key/add";
        var file=$("#secretKeyUpload")[0].files[0];
        if(operation=="update" || file!=undefined){
            if(file!=undefined){
                var filename=file.name;
                var suffix=filename.substring(filename.length-4,filename.length);
                if(suffix.toLowerCase()=="json"){
                    var path="";
                    if (window.createObjcectURL != undefined) {
                        path = window.createOjcectURL(file);
                    } else if (window.URL != undefined) {
                        path = window.URL.createObjectURL(file);
                    } else if (window.webkitURL != undefined) {
                        path = window.webkitURL.createObjectURL(file);
                    }
                    if(path!=""){
                        $.getJSON(path,function (data) {
                            $("#secretKey").val(JSON.stringify(data));
                        });
                        formData.append("file",file);
                    }

                }else{
                    alert("请选择正确的文件(json格式)！");
                }
            }

            if(operation=="update"){
                formData.append("id",id);
                url="/site/site/key/update/"+skId;
            }else{
                formData.append("siteId",$("#siteId").val());
            }
            formData.append("tableId",$("#tableId").val());
            //执行ajax
            var request = new XMLHttpRequest();
            request.open("POST", url,true);
            request.onreadystatechange = function(){
                if(request.readyState==4){
                    if(request.status==200){
                        var data=JSON.parse(request.responseText);
                        alert(data.basic.msg);
                        window.location.href="/site/site/key/update?siteId="+$("#siteId").val();
                    }else {
                        alert("上传失败，请重试！");
                    }
                }
            };
            request.send(formData);

        }else{
            alert("请选择需要上传的密钥文件！");
        }
    }else{
        alert("请输入资源视图ID！");
    }
});
上传文件html：

<input type='file' id="secretKeyUpload" name="file">

后台接收代码：

@ResponseBody
@RequestMapping(value = "/add")
public ResultBase siteKeyAdd(HttpServletRequest request, @RequestParam("file") MultipartFile file, String tableId, Integer siteId){

    //上传的json文件的临时存储路径
    String fileName=file.getOriginalFilename();
    String path=SiteKeyController.class.getResource("/").toString().substring(6);
    File targetFile=new File(path,fileName);

    try{
        file.transferTo(targetFile);
        FileInputStream fileInputStream=new FileInputStream(targetFile);
        String secretKey = IOUtils.toString(fileInputStream);
        try{
            Map map=(Map)JSON.parse(secretKey);
        }catch (Exception e){
            fileInputStream.close();
            targetFile.delete();
            resultBase.basic.setMsg("密钥不是标准json格式！").setStatus(0);
            return resultBase;
        }
        gaSecretKeyInfo.setSecretKey(secretKey);
        //删除文件前关闭流，否则无法删除
        fileInputStream.close();
        targetFile.delete();
    }catch (Exception e){
        targetFile.deleteOnExit();
        e.printStackTrace();
        resultBase.basic.setMsg("秘钥上传异常！").setStatus(0);
        return resultBase;
    }
 　　dao层代码。。、、、、、
}