java多个文件压缩打包成zip下载
如果实现批量操作一些文件，使之压缩打包成zip下载？
具体实现步骤如下：
- 设置下载文件名编码
- 创建zip输出流ZipOutputStream
- 将需要下载的文件流循环写入ZipOutputStream
- 关闭各个流
话不多说，直接上代码
service层方法（关键）：
@Override
public void downloadAllFile(HttpServletResponse response, String processInstanceId) {
String downloadName = "xxx附件.zip";
try {
response.setContentType("multipart/form-data");
response.setHeader("Content-Disposition", "attachment;fileName=" + URLEncoder.encode(downloadName, "UTF-8"));
} catch (UnsupportedEncodingException e) {
throw new HrmsException("下载文件名编码时出现错误.", e);
}
OutputStream outputStream = null;
ZipOutputStream zos = null;
try {
outputStream = response.getOutputStream();
zos = new ZipOutputStream(outputStream);
// 将文件流写入zip中
downloadTolocal(zos,processInstanceId);
} catch (IOException e) {
logger.error("downloadAllFile-xxx下载全部附件失败，processInstanceId=[{}],错误信息=[{}]",processInstanceId,e);
}finally {
if(zos != null) {
try {
zos.close();
} catch (Exception e2) {
logger.info("关闭输入流时出现错误",e2);
}
}
if(outputStream != null) {
try {
outputStream.close();
} catch (Exception e2) {
logger.info("关闭输入流时出现错误",e2);
}
}
}
}
private void downloadTolocal(ZipOutputStream zos,String processInstanceId) throws IOException {
Map<String, String> pm = new HashMap<String, String>();
pm.put("processInstanceId", processInstanceId);
//获取文件信息（此处为业务代码，可根据自己的需要替换）
List<Map<String,String>> fileInfoList = this.findByStatement("getAllFileInfo",pm);
for (Map<String, String> map : fileInfoList) {
String fileId = map.get("fileId");
//文件名称（带后缀）
String fileName = map.get("fileName");
InputStream is = null;
BufferedInputStream in = null;
byte[] buffer = new byte[1024];
int len;
//创建zip实体（一个文件对应一个ZipEntry）
ZipEntry entry = new ZipEntry(fileName);
try {
//获取需要下载的文件流
is = ossFileManager.getFile(fileId);
in = new BufferedInputStream(is);
zos.putNextEntry(entry);
//文件流循环写入ZipOutputStream
while ((len = in.read(buffer)) != -1 ) {
zos.write(buffer, 0, len);
}
} catch (Exception e) {
logger.info("xxx--下载全部附件--压缩文件出错",e);
}finally {
if(entry != null) {
try {
zos.closeEntry();
} catch (Exception e2) {
logger.info("xxx下载全部附件--zip实体关闭失败",e2);
}
}
if(in != null) {
try {
in.close();
} catch (Exception e2) {
logger.info("xxx下载全部附件--文件输入流关闭失败",e2);
}
}
if(is != null) {
try {
is.close();
}catch (Exception e) {
logger.info("xxx下载全部附件--输入缓冲流关闭失败",e);
}
}
}
}
}
controller层接口：
/** * 下载全部附件 */
@RequestMapping(value = "/downloadAllFile/{processInstanceId}", method = RequestMethod.GET)
public void downloadAllFile(HttpServletResponse response,@PathVariable("processInstanceId") String processInstanceId) {
floCnbCompetitionLimitService.downloadAllFile(response,processInstanceId);
}
前端调用接口，便可在浏览器中直接下载zip文档下来
