需求:Java根据Url把多个文件下载到指定的文件夹目录，然后再将文件夹目录打包成zip导出.
@Slf4j
@Controller("test")
@Api(value = "zip文件上传API", tags = {"zip文件上传"})
public class Download {
@Autowired
private RecordFileMapper recordFileMapper;
@Autowired
private AttachmentRepository attachmentRepository;
/**
* 文件下载
* @param
* @param response
* @throws Exception
*/
@GetMapping("checkDownloadFile")
@ResponseBody
public void checkDownloadFile(@ApiParam("id") @RequestParam("id") String id,
HttpServletResponse response) throws Exception {
//根据id获取到你的文件url
QueryWrapper<RecordFile> recordFileQueryWrapper = new QueryWrapper<>();
recordFileQueryWrapper.eq("recordid", id);
List<RecordFile> recordFileList = recordFileMapper.selectList(recordFileQueryWrapper);
List<Attachment> attachmentList = new ArrayList<>();
for (int k = 0; k < recordFileList.size(); k++) {
//获取id
if (recordFileList != null) {
RecordFile recordFile = recordFileList.get(k);
//根据文件id查询neo4j里面的文件信息
Attachment attachment = attachmentRepository.queryByid(Long.valueOf(recordFile.getFileid()));
attachmentList.add(attachment);
}
}
//判断你的集合是否为=1,如果是1 是单个文件直接执行下面的代码
if(attachmentList.size()==1){
String url=attachmentList.get(0).getPath();
HttpURLConnection conn = null;
InputStream fis = null;
try {
File file = new File(url);
// 取得文件的后缀名。
String ext = file.getName().substring(file.getName().lastIndexOf(".") + 1).toLowerCase();
StringBuffer buffername = new StringBuffer(url.substring(url.lastIndexOf("/")+1));
// 取的文件名
String filename = buffername.toString();
URL path = new URL(url);
conn = (HttpURLConnection) path.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5 * 1000);
// 通过输入流获取数据
fis = conn.getInputStream();
byte[] buffer = readInputStream(fis);
if (null != buffer && buffer.length > 0) {
// 清空response
response.reset();
// 设置response的Header
String [] name=filename.split("\\?");
response.addHeader("Content-Disposition", "attachment;filename=" + new String(name[0].getBytes(),"ISO8859-1"));
response.addHeader("Content-Length", "" + buffer.length);
OutputStream toClient = response.getOutputStream();
//response.setContentType("application/x-msdownload");
response.setContentType("application/octet-stream");
toClient.write(buffer);
toClient.flush();
toClient.close();
}
} catch (IOException ex) {
log.error("下载文件异常:", ex);
throw new Exception("下载异常，请稍后再试。");
} finally {
if (conn != null) {
conn.disconnect();
}
if (fis != null) {
try {
fis.close();
} catch (IOException ioe) {
log.error("下载文件->关闭流异常:", ioe);
}
}
}
}else{
//多个的需要先打包再下载
//定义压缩地址
String fileStr = "D:\\image\\";
String zipFileStr = "D:\\imageZip\\项目统计进展报告.zip";
//构建map,执行压缩
List<Map<String, String>> imageUrls = new ArrayList<>();
Map<String, String> imageUrl = new HashMap<>();
//循环构建map
for(int i=0;i<attachmentList.size();i++){
imageUrl.put(attachmentList.get(i).getName(), attachmentList.get(i).getPath());
imageUrls.add(imageUrl);
}
FileZipUtils.FileMain(imageUrls,fileStr,zipFileStr);
//下载文件
String url=zipFileStr;
try {
// path是指欲下载的文件的路径。
File file = new File(url);
// 取得文件名。
String filename = file.getName();
// 取得文件的后缀名。
String ext = filename.substring(filename.lastIndexOf(".") + 1).toUpperCase();
// 以流的形式下载文件。
InputStream fis = new BufferedInputStream(new FileInputStream(url));
byte[] buffer = new byte[fis.available()];
fis.read(buffer);
fis.close();
// 清空response
response.reset();
// 设置response的Header
response.addHeader("Content-Disposition", "attachment;filename=" + java.net.URLEncoder.encode(filename, "utf-8"));
response.setContentType("text/html;charset=utf-8");
response.addHeader("Content-Length", "" + file.length());
OutputStream toClient = new BufferedOutputStream(response.getOutputStream());
response.setContentType("application/octet-stream");
toClient.write(buffer);
toClient.flush();
toClient.close();
} catch (IOException ex) {
log.error("下载文件异常:", ex);
throw new Exception("下载异常，请稍后再试。");
} finally {
try {
//删除压缩包
File zfile = new File(url);
zfile.delete();
}catch (Exception e){
e.printStackTrace();
}
}
}
}
@GetMapping("checkDownload")
@ResponseBody
public void checkDownload(@ApiParam("文件地址") @RequestParam("url") String url,
HttpServletResponse response) throws Exception {
HttpURLConnection conn = null;
InputStream fis = null;
try {
File file = new File(url);
// 取得文件的后缀名。
String ext = file.getName().substring(file.getName().lastIndexOf(".") + 1).toLowerCase();
StringBuffer buffername = new StringBuffer(url.substring(url.lastIndexOf("/")+1));
// 取的文件名
String filename = buffername.toString();
URL path = new URL(url);
conn = (HttpURLConnection) path.openConnection();
conn.setRequestMethod("GET");
conn.setConnectTimeout(5 * 1000);
// 通过输入流获取数据
fis = conn.getInputStream();
byte[] buffer = readInputStream(fis);
if (null != buffer && buffer.length > 0) {
// 清空response
response.reset();
// 设置response的Header
String [] name=filename.split("\\?");
response.addHeader("Content-Disposition", "attachment;filename=" + new String(name[0].getBytes(),"ISO8859-1"));
response.addHeader("Content-Length", "" + buffer.length);
OutputStream toClient = response.getOutputStream();
//response.setContentType("application/x-msdownload");
response.setContentType("application/octet-stream");
toClient.write(buffer);
toClient.flush();
toClient.close();
}
} catch (IOException ex) {
log.error("下载文件异常:", ex);
throw new Exception("下载异常，请稍后再试。");
} finally {
if (conn != null) {
conn.disconnect();
}
if (fis != null) {
try {
fis.close();
} catch (IOException ioe) {
log.error("下载文件->关闭流异常:", ioe);
}
}
}
}
/**
* 从输入流中获取数据
*
* @param fis : InputStream
* @return byte[]
* @author chenp
* @date 2023/3/28 11:31
*/
private byte[] readInputStream(InputStream fis) throws IOException {
ByteArrayOutputStream outStream = new ByteArrayOutputStream();
byte[] buffer = new byte[1024];
int len = 0;
while ((len = fis.read(buffer)) != -1) {
outStream.write(buffer, 0, len);
}
fis.close();
return outStream.toByteArray();
}
}