问题描述

用Ajax请求道action中执行了方法但没有显示结果怎么回事

Ajax中
//导出方法
function exportGo(url,params,grid) {

     $.messager.confirm('提示','您正要导出此项 !<br />请确定继续?',function(r){
         if(r){
             doAjax3("", url, grid, params, "");
         }
    });
}

function doAjax3(form,url,grid,param,msg){
    $.ajax({
        url: url,
        type: 'POST',
        cache: false,
        async: false,
        contentType:"application/json",
    //  dataType : 'json',
        data:  param,
        success: function(data, textStatus, jqXHR) {
            alert(data);
            if (!isNull(grid)) {
                grid.load({page:1});
            }
            if(!isNull(form)){
                form.resetForm();
            }

        },
        error:function(msg,textStatus, errorThrown) {
            alert(errorThrown);
            alert("网络错误或者处理异常，请重试或者联系管理员处理！错误信息：" + msg.responseText);
        }
   });
}

action中
/**
* 导出model的xml文件
*/
@RequestMapping(value = "export/{modelId}")
@OperatingLog(function="导出文件")
public void export(@PathVariable("modelId") String modelId,
HttpServletResponse response) {
try {
Model modelData = repositoryService.getModel(modelId);
BpmnJsonConverter jsonConverter = new BpmnJsonConverter();
JsonNode editorNode = new ObjectMapper().readTree(repositoryService
.getModelEditorSource(modelData.getId()));
BpmnModel bpmnModel = jsonConverter.convertToBpmnModel(editorNode);
BpmnXMLConverter xmlConverter = new BpmnXMLConverter();
byte[] bpmnBytes = xmlConverter.convertToXML(bpmnModel);

        ByteArrayInputStream in = new ByteArrayInputStream(bpmnBytes);
        IOUtils.copy(in, response.getOutputStream());
        String filename = bpmnModel.getMainProcess().getId()
                + ".bpmn20.xml";
        response.setHeader("Content-Disposition", "attachment; filename="
                + filename);
        response.flushBuffer();
    } catch (Exception e) {
        log.error("导出model的xml文件失败：modelId={}", modelId, e);
    }
}