Http请求传json数据中文乱码问题

业务场景：调easyui的dialog打开一个弹窗，传参是用json封装的，而且有中文，然后在极速模式是正常的，在ie11测试发现中文出现乱码了

var params = JSON.stringify(writParamList);
top.dialog({
             id: 'noticeList',
             title:'列表',
             width:900,
            height:500,
            url:'${root}/notice/multiNoticeList.do?params='+params,
            onclose:function(){
                        //location.reload();
             }
}).showModal();      

String params = request.getParameter("params");
        logger.info("文书参数转换前:》》"+params);
        params=StringEscapeUtils.unescapeJava(params);
        logger.info("文书参数转换后:》》"+params);
        ObjectMapper mapper = new ObjectMapper();
        JavaType javaType = mapper.getTypeFactory().constructParametricType(List.class, FormModel.class);
        /*List<FormModel> writUnionFormList = 
                JSON.parseArray(params, FormModel.class);*/
        List<FormModel> writUnionFormList=new ArrayList<FormModel>();
        try {
            writUnionFormList = (List<FormModel>)mapper.readValue(params, javaType);
        } catch (JsonParseException e) {
            e.printStackTrace();
        } catch (JsonMappingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }      

var params = JSON.stringify(writParamList);
top.dialog({
             id: 'noticeList',
             title:'列表',
             width:900,
            height:500,
            url:'${root}/notice/multiNoticeList.do?params='+encodeURI(encodeURI(params)),
            onclose:function(){
                        //location.reload();
             }
}).showModal();      

String params = request.getParameter("params");
        logger.info("文书参数转换前:》》"+params);
        //params=StringEscapeUtils.unescapeJava(params);
//      byte[] buffer=Base64Utils.decodeFromString(params);
//      params = new String(buffer);
         try {
             params=URLDecoder.decode(params,"utf-8");
        } catch (UnsupportedEncodingException e1) {
            e1.printStackTrace();
        }
        logger.info("文书参数转换后:》》"+params);
        ObjectMapper mapper = new ObjectMapper();
        JavaType javaType = mapper.getTypeFactory().constructParametricType(List.class, ApprWritUnionFormModel.class);
        /*List<FormModel> writUnionFormList = 
                JSON.parseArray(params, FormModel.class);*/
        List<FormModel> writUnionFormList=new ArrayList<FormModel>();
        try {
            writUnionFormList = (List<FormModel>)mapper.readValue(params, javaType);
        } catch (JsonParseException e) {
            e.printStackTrace();
        } catch (JsonMappingException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }