Map<String, String> data = new HashMap<String, String>();

                   /***银联全渠道系统，产品参数，除了encoding自行选择外其他不需修改***/

                   //版本号 全渠道默认值

                   data.put("version", DemoBase.version);              

                   //字符集编码 可以使用UTF-8,GBK两种方式

                   data.put("encoding", DemoBase.encoding_UTF8);        

                   //签名方法

                   data.put("signMethod", SDKConfig.getConfig().getSignMethod());

                   //交易类型 76-对账文件下载

                   data.put("txnType", "76");                          

                   //交易子类型 01-对账文件下载

                   data.put("txnSubType", "01");                       

                   //业务类型，固定

                   data.put("bizType", "000000");                     

                   /***商户接入参数***/

                   //接入类型，商户接入填0，不需修改

                   data.put("accessType", "0"); 

                   //商户代码，请替换正式商户号测试，如使用的是自助化平台注册的777开头的商户号，该商户号没有权限测文件下载接口的，

                   //请使用测试参数里写的文件下载的商户号和日期测。如需777商户号的真实交易的对账文件，请使用自助化平台下载文件。

                   data.put("merId", merId);

                   //清算日期，如果使用正式商户号测试则要修改成自己想要获取对账文件的日期， 测试环境如果使用700000000000001商户号则固定填写0119

                   data.put("settleDate", settleDate);

                   //订单发送时间，取系统时间，格式为YYYYMMDDhhmmss，必须取当前时间，否则会报txnTime无效

                   data.put("txnTime",DemoBase.getCurrentTime());

                   //文件类型，一般商户填写00即可

                   data.put("fileType", "00");                         

                   /**请求参数设置完毕，以下对请求参数进行签名并发送http post请求，接收同步应答报文------------->**/

                   Map<String, String> reqData = AcpService.sign(data,DemoBase.encoding_UTF8);              

                   //报文中certId,signature的值是在signData方法中获取并自动赋值的，只要证书配置正确即可。

                   String url = SDKConfig.getConfig().getFileTransUrl();     

                   //获取请求银联的前台地址：对应属性文件acp_sdk.properties文件中的acpsdk.fileTransUrl

                   Map<String, String> rspData = AcpService.post(reqData, url,DemoBase.encoding_UTF8);

if(!rspData.isEmpty()){

                            if(AcpService.validate(rspData, DemoBase.encoding_UTF8)){

                                     LogUtil.writeLog("验证签名成功");

                                     String respCode = rspData.get("respCode");

                                     if("00".equals(respCode)){

                                               //交易成功，解析返回报文中的fileContent并落地

                                               String zipFilePath = AcpService.deCodeFileContent(rspData,"d:\",DemoBase.encoding_UTF8);

                                               //对落地的zip文件解压缩并解析

                                               String outPutDirectory ="d:\";

                                               List<String> fileList = DemoBase.unzip(zipFilePath, outPutDirectory);

                                               //解析ZM，ZME文件

                                              for(String file : fileList){

                                                        if(file.indexOf("ZM_")!=-1){

                                                                 List<Map> ZmDataList = DemoBase.parseZMFile(file);

                                                                 fileContentDispaly = DemoBase.getFileContentTable(ZmDataList,file);

                                                        }else if(file.indexOf("ZME_")!=-1){

                                                                 DemoBase.parseZMEFile(file);

                                                        }

                                               }

                                               //TODO

                                     }else{

                                               //其他应答码为失败请排查原因

                                               //TODO

                                     }

                            }else{

                                     LogUtil.writeErrorLog("验证签名失败");

                                     //TODO 检查验证签名失败的原因

                            }

                   }else{

                            //未返回正确的http状态

                            LogUtil.writeErrorLog("未获取到返回报文或返回http状态码非200");

                   }

LogUtil.writeLog("BackRcvResponse接收后台通知开始");

String encoding = req.getParameter(SDKConstants.param_encoding);

// 获取银联通知服务器发送的后台通知参数

Map<String, String> reqParam = getAllRequestParam(req);

LogUtil.printRequestLog(reqParam);

Map<String, String> valideData = null;

if (null != reqParam && !reqParam.isEmpty()) {

Iterator<Entry<String, String>> it = reqParam.entrySet().iterator();

valideData = new HashMap<String, String>(reqParam.size());

 while (it.hasNext()) {

 Entry<String, String> e = it.next();

 String key = (String) e.getKey();

 String value = (String) e.getValue();

 valideData.put(key, value);

  }

  }

 //重要！验证签名前不要修改reqParam中的键值对的内容，否则会验签不过

 if (!AcpService.validate(valideData, encoding)) {

 LogUtil.writeLog("验证签名结果[失败].");

 //验签失败，需解决验签问题

 } else {

 LogUtil.writeLog("验证签名结果[成功].");

 //【注：为了安全验签成功才应该写商户的成功处理逻辑】交易成功，更新商户订单状态

 String orderId =valideData.get("orderId"); //获取后台通知的数据，其他字段也可用类似方式获取

 String respCode = valideData.get("respCode");

 }

 LogUtil.writeLog("BackRcvResponse接收后台通知结束");

 //返回给银联服务器http 200  状态码

resp.getWriter().print("ok");