java下载多个文件_Java实现zip多个文件分组下载

Myth丶恋晨 2022-11-05 09:59 234阅读 0赞

最近写了个批量导出文件的功能， 客户要求根据业务系统为条件分组导出系统附件

业务场景： 月度、季度、年度统计

条件： 根据不同的条件查出系统相关的附件，每个系统的文件要单独放在一个文件夹

根据系统分组

![5387fdab1452edd5ec2126e545089468.png][]

每个分组的附件

![93222505a232cf0899d6bcbd1c860cea.png][]

/\*\*

\* @param start\_time 开始时间

\* @param end\_time 结束时间

\* @param ids 选择数据的id

\* @param type 类型

\*/

@ApiOperation("分组下载")

@GetMapping("/generateFileGroupDownZip")

public BaseRetBean generateFileGroupDownZip(

@ApiParam(value = "开始时间",required = false) @RequestParam(value = "start\_time",required = false)String start\_time,

@ApiParam(value = "结束时间",required = false) @RequestParam(value = "end\_time",required = false) String end\_time,

@ApiParam(value = "主键编号",required = false) @RequestParam(value = "ids",required = false) List ids,

@ApiParam(value = "类型",required = false) @RequestParam(value = "type",required = false) Integer type,

HttpServletRequest req, HttpServletResponse response) throws Exception \{

BaseRetBean baseRetBean = new BaseRetBean();

// 获取session数据

GmAppSessionConfig sessionConfig=getSession(req);

// 查询语句

List gmFileBeans = workOrderService.generateFileGroupDownZip(start\_time, end\_time, ids, type, sessionConfig.getDeptid());

// 判断是否为空， 如果为空注解结束

if (gmFileBeans.size()==0) \{

baseRetBean.setRet(1);

baseRetBean.setMsg("没有文件");

return baseRetBean;

//设置最终输出zip文件的目录+文件名

SimpleDateFormat formatter = new SimpleDateFormat("yyyyMMddHHmmss");

String zipFileName = formatter.format(new Date())+".zip";

// 定义zip输出流

ZipOutputStream zipStream = null;

BufferedInputStream bufferStream = null;

File zipFile = new File(zipFileName);

try\{

//构造最终压缩包的输出流

zipStream = new ZipOutputStream(new FileOutputStream(zipFile));

// 通过lambda表达式分组

Map> collect = gmFileBeans.stream().collect(Collectors.groupingBy(GmFileQueryBean::getSys\_name));

// 遍历分组

for (Map.Entry> entryUser : collect.entrySet()) \{

// 获取分组键

String key = entryUser.getKey();

// 获取分组值

List entryUserList = entryUser.getValue();

// 如果分组值不为空则遍历数组

if (entryUserList.size()>0) \{

// 遍历分组值列表

for (GmFileQueryBean gmFileQueryBean : entryUserList) \{

// 获取base64存储的数据

String base64Str = gmFileQueryBean.getData();

// 获取后缀

String suffix = gmFileQueryBean.getType();

// 数据为空

if (base64Str == null) \{

baseRetBean.setRet(0);

baseRetBean.setMsg("文件为空");

return baseRetBean;

BASE64Decoder decoder = new BASE64Decoder();

// Base64解码,对字节数组字符串进行Base64解码并生成文件

byte\[\] byt = decoder.decodeBuffer(base64Str);

for (int a = 0, len = byt.length; a < len; ++a) \{

// 调整异常数据

if (byt\[a\] < 0) \{

byt\[a\] += 256;

InputStream input = new ByteArrayInputStream(byt);

/\*\*

\* 文件和文件夹命名

\* 文件：名称 + 后缀 (系统名-公单类型-文件类型-随机号-后缀)

\* 文件夹："\\\\" + 文件名 + "\\\\"

\* 组合使用： 文件夹 + 文件

\*/

ZipEntry zipEntry = new ZipEntry( "\\\\" + key + "\\\\" + gmFileQueryBean.getSys\_name() + "-" +

gmFileQueryBean.getWork\_type\_name() + "-" + gmFileQueryBean.getFile\_type\_name() + "-" + StringUtil.getRandomStr(true, 4) + gmFileQueryBean.getType());

zipStream.putNextEntry(zipEntry);

bufferStream = new BufferedInputStream(input, 1024 \* 10);

int read = 0;

byte\[\] buf = new byte\[1024 \* 10\];

while ((read = bufferStream.read(buf, 0, 1024 \* 10)) != -1) \{

zipStream.write(buf, 0, read);

\} catch (Exception e) \{

e.printStackTrace();

\} finally \{

//关闭流

try \{

if(null != bufferStream) \{

bufferStream.close();

if(null != zipStream)\{

zipStream.flush();

zipStream.close();

\} catch (IOException e) \{

e.printStackTrace();

//判断系统压缩文件是否存在：true-把该压缩文件通过流输出给客户端后删除该压缩文件 false-未处理

if(zipFile.exists())\{

// 调用下载方法

groupDownZip(response,zipFileName);

zipFile.delete();

baseRetBean.setRet(1);

baseRetBean.setMsg("查询成功");

return baseRetBean;

/\*\*

\* @param response http相应

\* @param filename 文件名

\*/

private void groupDownZip(HttpServletResponse response, String filename)\{

if (filename != null) \{

FileInputStream inputStream = null;

BufferedInputStream bufferedInputStream = null;

OutputStream outputStream = null;

try \{

File file = new File(filename);

if (file.exists()) \{

//设置Headers

response.setHeader("Content-Type","application/octet-stream");

//设置下载的文件的名称-该方式已解决中文乱码问题

response.setHeader("Content-Disposition","attachment;filename=" + new String(filename.getBytes(), "utf-8"));

inputStream = new FileInputStream(file);

bufferedInputStream =new BufferedInputStream(inputStream);

outputStream = response.getOutputStream();

byte\[\] buffer = new byte\[1024\];

int lenth = 0;

while((lenth = bufferedInputStream.read(buffer)) != -1)\{

outputStream.write(buffer,0,lenth);

\}else\{

String error = Base64Util.encode("文件内容为空");

\}catch(IOException ex)\{

ex.printStackTrace();

\}finally \{

try\{

if(inputStream != null)\{

inputStream.close();

if( bufferedInputStream != null )\{

bufferedInputStream.close();

if( outputStream != null)\{

outputStream.flush();

outputStream.close();

\}catch (IOException e)\{

e.printStackTrace();

[5387fdab1452edd5ec2126e545089468.png]: /images/20221023/7e960e75ae5d4fee917995e431f05ed4.png
[93222505a232cf0899d6bcbd1c860cea.png]: /images/20221023/a2aecfe1c6844f1fb87da67025c847d2.png