SpringBoot实现本地(网络)文件下载和zip压缩包批量下载
一、前置条件
demo中，将多个文件通过zip的形式进行下载，所以需要引入以下maven坐标：
<dependency> <groupId>org.apache.commons</groupId> <artifactId>commons-compress</artifactId> <version>1.20</version> </dependency>
为了更好的代码可读性，将针对本地、网络文件下载、zip压缩包批量下载封装一个工具类，代码如下：
下载实现的核心就是下面的工具类代码，可以在任意的项目中进行使用；
import org.apache.commons.compress.archivers.ArchiveEntry; import org.apache.commons.compress.archivers.zip.Zip64Mode; import org.apache.commons.compress.archivers.zip.ZipArchiveEntry; import org.apache.commons.compress.archivers.zip.ZipArchiveOutputStream; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import javax.activation.MimetypesFileTypeMap; import javax.servlet.ServletOutputStream; import javax.servlet.http.HttpServletRequest; import javax.servlet.http.HttpServletResponse; import java.io.*; import java.net.HttpURLConnection; import java.net.MalformedURLException; import java.net.URL; import java.net.URLEncoder; import java.text.SimpleDateFormat; import java.util.Date; import java.util.List; import java.util.Map; public class FileUtil { private static final Logger logger = LoggerFactory.getLogger(FileUtil.class); private static MimetypesFileTypeMap mimetypesFileTypeMap; /** * 下载http文件流 * * @param urlStr * @param request * @param response * @param fileName * @return */ public static void downloadHttpFile(String urlStr, HttpServletRequest request, HttpServletResponse response, String fileName) { ServletOutputStream out = null; InputStream inputStream = null; try { URL url = new URL(urlStr); HttpURLConnection conn = (HttpURLConnection) url.openConnection(); //得到输入流 inputStream = conn.getInputStream(); //获取自己数组 byte[] getData = FileUtil.inputStreamToByte(inputStream); // 下载 out = response.getOutputStream(); long contentLength = getData.length; FileUtil.setResponse(fileName, contentLength, request, response); out.write(getData); out.flush(); } catch (Exception e) { throw new RuntimeException("下载失败!"); } finally { try { if (out != null) { out.close(); } if (inputStream != null) { inputStream.close(); } } catch (IOException e) { e.printStackTrace(); } } } //File、FileInputStream 转换为byte数组 public static byte[] inputStreamToByte(InputStream inputStream) { try { byte[] buffer = new byte[1024]; int len = 0; ByteArrayOutputStream bos = new ByteArrayOutputStream(); while ((len = inputStream.read(buffer)) != -1) { bos.write(buffer, 0, len); } bos.close(); return bos.toByteArray(); } catch (Exception e) { throw new RuntimeException("文件转换失败!"); } } /** * 下载文件流 * * @param file * @param request * @param response * @param fileName * @return */ public static void downloadFile(File file, HttpServletRequest request, HttpServletResponse response, String fileName) { if (file != null && file.exists() && file.length() > 0L) { try { RandomAccessFile randomFile = new RandomAccessFile(file, "r"); Throwable var5 = null; Object var54; try { ServletOutputStream out = response.getOutputStream(); Throwable var7 = null; try { long contentLength = randomFile.length(); String range = request.getHeader("Range"); long start = 0L; long end = 0L; if (range != null && range.startsWith("bytes=")) { String[] values = range.split("=")[1].split("-"); start = Long.parseLong(values[0]); if (values.length > 1) { end = Long.parseLong(values[1]); } } int requestSize; if (end != 0L && end > start) { requestSize = Long.valueOf(end - start + 1L).intValue(); } else { requestSize = 2147483647; } FileUtil.setResponse(fileName, contentLength, request, response); randomFile.seek(start); byte[] buffer; for (int needSize = requestSize; needSize > 0; needSize -= buffer.length) { buffer = new byte[1024]; int len = randomFile.read(buffer); if (needSize < buffer.length) { out.write(buffer, 0, needSize); } else { out.write(buffer, 0, len); if (len < buffer.length) { break; } } } out.flush(); var54 = null; } catch (Throwable var47) { var7 = var47; throw var47; } finally { if (out != null) { if (var7 != null) { try { out.close(); } catch (Throwable var46) { var7.addSuppressed(var46); } } else { out.close(); } } } } catch (Throwable var49) { var5 = var49; throw var49; } finally { if (randomFile != null) { if (var5 != null) { try { randomFile.close(); } catch (Throwable var45) { var5.addSuppressed(var45); } } else { randomFile.close(); } } } } catch (IOException var51) { logger.debug(var51.getMessage(), var51); throw new RuntimeException(var51.getMessage()); } } else { throw new RuntimeException("文件为空或不存在！"); } } /** * @param fileName * @param contentLength * @param request * @param response * @return */ public static void setResponse(String fileName, long contentLength, HttpServletRequest request, HttpServletResponse response) { try { response.setContentType(FileUtil.getContentType("0.jpg")); boolean isPreview = "preview".equalsIgnoreCase(request.getParameter("source")); response.addHeader("Content-Disposition", (!isPreview ? "attachment; " : "") + "filename*=utf-8'zh_cn'" + URLEncoder.encode(fileName, "UTF-8")); response.setHeader("Accept-Ranges", "bytes"); String range = request.getHeader("Range"); if (range == null) { response.setHeader("Content-Length", String.valueOf(contentLength)); } else { response.setStatus(206); long requestStart = 0L; long requestEnd = 0L; String[] ranges = range.split("="); if (ranges.length > 1) { String[] rangeDatas = ranges[1].split("-"); requestStart = Long.parseLong(rangeDatas[0]); if (rangeDatas.length > 1) { requestEnd = Long.parseLong(rangeDatas[1]); } } long length = 0L; if (requestEnd > 0L) { length = requestEnd - requestStart + 1L; response.setHeader("Content-Length", String.valueOf(length)); response.setHeader("Content-Range", "bytes " + requestStart + "-" + requestEnd + "/" + contentLength); } else { length = contentLength - requestStart; response.setHeader("Content-Length", String.valueOf(length)); response.setHeader("Content-Range", "bytes " + requestStart + "-" + (contentLength - 1L) + "/" + contentLength); } } } catch (Exception e) { throw new RuntimeException("response响应失败!"); } } public static String getContentType(String fileName) { if (mimetypesFileTypeMap == null) { mimetypesFileTypeMap = new MimetypesFileTypeMap(); } return mimetypesFileTypeMap.getContentType(fileName); } /** * 将磁盘的多个文件打包成压缩包并输出流下载 * * @param pathList * @param request * @param response */ public static void zipDirFileToFile(List<Map<String, String>> pathList, HttpServletRequest request, HttpServletResponse response) { try { // 设置response参数并且获取ServletOutputStream ZipArchiveOutputStream zous = getServletOutputStream(response); for (Map<String, String> map : pathList) { String fileName = map.get("name"); File file = new File(map.get("path")); InputStream inputStream = new FileInputStream(file); setByteArrayOutputStream(fileName, inputStream, zous); } zous.close(); } catch (Exception e) { e.printStackTrace(); } } /** * 将网络url资源文件的多个文件打包成压缩包并输出流下载 * * @param pathList * @param request * @param response */ public static void zipUrlToFile(List<Map<String, String>> pathList, HttpServletRequest request, HttpServletResponse response) { try { // 设置response参数并且获取ServletOutputStream ZipArchiveOutputStream zous = getServletOutputStream(response); for (Map<String, String> map : pathList) { String fileName = map.get("name"); InputStream inputStream = getInputStreamFromUrl(map.get("path")); setByteArrayOutputStream(fileName, inputStream, zous); } zous.close(); } catch (Exception e) { e.printStackTrace(); } } private static ZipArchiveOutputStream getServletOutputStream(HttpServletResponse response) throws Exception { String outputFileName = "文件" + new SimpleDateFormat("yyyyMMddHHmmss").format(new Date()) + ".zip"; response.reset(); response.setHeader("Content-Type", "application/octet-stream"); response.setHeader("Content-Disposition", "attachment;filename=" + URLEncoder.encode(outputFileName, "UTF-8")); response.setHeader("Pragma", "no-cache"); response.setHeader("Cache-Control", "no-cache"); ServletOutputStream out = response.getOutputStream(); ZipArchiveOutputStream zous = new ZipArchiveOutputStream(out); zous.setUseZip64(Zip64Mode.AsNeeded); return zous; } private static void setByteArrayOutputStream(String fileName, InputStream inputStream, ZipArchiveOutputStream zous) throws Exception { ByteArrayOutputStream baos = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len; while ((len = inputStream.read(buffer)) != -1) { baos.write(buffer, 0, len); } baos.flush(); byte[] bytes = baos.toByteArray(); //设置文件名 ArchiveEntry entry = new ZipArchiveEntry(fileName); zous.putArchiveEntry(entry); zous.write(bytes); zous.closeArchiveEntry(); baos.close(); } /** * 通过网络地址获取文件InputStream * * @param path 地址 * @return */ private static InputStream getInputStreamFromUrl(String path) { URL url = null; InputStream is = null; try { url = new URL(path); } catch (MalformedURLException e) { e.printStackTrace(); } try { HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setDoInput(true); conn.connect(); is = conn.getInputStream(); } catch (IOException e) { e.printStackTrace(); } return is; } }
二、单一文件下载
2.1、本地文件下载
Controller：
@RestController @RequestMapping("/test") public class TestController { @Resource private HttpServletResponse response; @Resource private HttpServletRequest request; @GetMapping(value = "/down/file") public void downloadFileStream() { // 文件本地位置 String filePath = "C:\\Users\\LiGezZ\\Desktop\\测试文件.txt"; // 文件名称 String fileName = "测试文件.txt"; File file = new File(filePath); FileUtil.downloadFile(file, request, response, fileName); // 浏览器访问：http://x.x.x.x/test/down/file } }
2.2、网络文件下载
注意： 通过网络请求下载时，设置的fileName一定要与http资源的后缀一致；
Controller：
@RestController @RequestMapping("/test") public class TestController { @Resource private HttpServletResponse response; @Resource private HttpServletRequest request; @GetMapping(value = "/down/file/http") public void downloadFileHttpStream() { // 文件网络地址 String urlStr = "https://code.jquery.com/jquery-3.6.0.js"; // 文件名称 String fileName = "测试文件.js"; FileUtil.downloadHttpFile(urlStr, request, response, fileName); // 浏览器访问：http://x.x.x.x/test/down/file/http } }
三、zip压缩包批量下载
3.1、本地文件批量下载
@RestController @RequestMapping("/test") public class TestController { @Resource private HttpServletResponse response; @Resource private HttpServletRequest request; @GetMapping(value = "/down/zip") public void downloadZipStream() { List<Map<String, String>> mapList = new ArrayList<>(); String basePath = "C:\\Users\\LiGezZ\\Desktop\\测试文件_"; // 模拟下载本地的5个文件，分别为测试文件1~5 for (int i = 1; i <= 5; i++) { Map<String, String> map = new HashMap<>(); map.put("path", basePath + i + ".txt"); map.put("name", "测试文件_" + i + ".txt"); mapList.add(map); } FileUtil.zipDirFileToFile(mapList, request, response); // 浏览器访问：http://x.x.x.x/test/down/zip } }
效果：
3.2、网络文件批量下载
注意： 通过网络请求下载时，设置的fileName一定要与http资源的后缀一致；
@RestController @RequestMapping("/test") public class TestController { @Resource private HttpServletResponse response; @Resource private HttpServletRequest request; @GetMapping(value = "/down/zip/http") public void downloadZipHttpByDataStream() { List<Map<String, String>> mapList = new ArrayList<>(); String urlStr = "https://code.jquery.com/jquery-3.6.0.js"; // 模拟下载本地的5个文件，分别为测试文件1~5 for (int i = 1; i <= 5; i++) { Map<String, String> map = new HashMap<>(); map.put("path", urlStr); map.put("name", "测试文件_" + i + ".js"); mapList.add(map); } FileUtil.zipUrlToFile(mapList, request, response); // 浏览器访问：http://x.x.x.x/test/down/zip/http } }
效果：
