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JAVA 大文件压缩极速下载
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JAVA 大文件压缩极速下载
前言
之前大/多文件压缩 900M下载需要7分钟左右，是因为没有优化代码，网上的代码直接复制粘贴能跑就OK，后来因为需求要求大文件1分钟左右下载完，于是各种百度，各种试验，最终产出了2种方案，一种是找迅雷接口，借助迅雷将多文件大文件下载，这种效率很高，而且不占JAVA JVM内耗，但老板觉得用这软件还得装一个插件，于是另想办法，这个方法于是横空出世，900M 压缩仅20秒左右，下载到本地是看网络流量大小。
这里感谢这位博主，大家可以看看这位博主的，我是直接在此博主的代码基础上改进了以迎合我的需求。
https://blog.csdn.net/ahau10/article/details/52550430/
以下直接代码
以下是controller代码(不重要) 代码片.
@ResponseBody //高速压缩下载 2019.6.20
@RequestMapping(value = "/downloadfileorfolderforzip")
public void downloadfileorfolderforzip(String urlsStr, HttpServletResponse response, HttpSession session, HttpServletRequest request) throws Exception {
Cookie[] cookies = request.getCookies();
if (null==cookies) {
System.out.println("没有cookie==============");
} else {
for(Cookie cookie : cookies){
if(cookie.getName().equals("downloadstatus")){
cookie.setValue(null);
cookie.setMaxAge(0);// 立即销毁cookie
cookie.setPath("/");
System.out.println("被删除的cookie名字为:"+cookie.getName());
response.addCookie(cookie);
break;
}
}
}
String[] urlss = urlsStr.split(",");
List<String> urls = new ArrayList<String>();
for(String str : urlss) {
urls.add(str);
}
String filename = new Date().getTime() + ".zip";
final File result = new File(this.finalDirPath + "linshi/" + filename);
new HighEffiCompressZipTest().createZipFile(urls, result);
BufferedInputStream bufferedInputStream = null;
OutputStream outputStream = null;
try {
response.setHeader("content-type", "application/octet-stream");
response.setContentType("application/octet-stream");
response.setCharacterEncoding("UTF-8");
response.setHeader("Content-Disposition", "attachment;filename=" + new String(filename.getBytes(), "iso-8859-1"));
byte[] buff = new byte[1024];
outputStream = response.getOutputStream();
FileInputStream fis = new FileInputStream(result);
bufferedInputStream = new BufferedInputStream(fis);
int num = bufferedInputStream.read(buff);
Cookie cookie = new Cookie("downloadstatus", String.valueOf(new Date().getTime()));
cookie.setMaxAge(5 * 60);// 设置为30min
cookie.setPath("/");
response.addCookie(cookie);
while (num != -1) {
outputStream.write(buff, 0, num);
outputStream.flush();
num = bufferedInputStream.read(buff);
}
System.out.println("==================complete========");
} catch (IOException e) {
logger.error(e.getMessage(), e);
e.printStackTrace();
throw e;
} finally {
System.out.println("==================complete========");
if (bufferedInputStream != null) {
bufferedInputStream.close();
}
}
}
以下是压缩代码(不重要) 代码片.
public class HighEffiCompressZipTest {
public static void main(String[] arg) throws Exception {
long begin = System.currentTimeMillis();
System.out.println(new Date());
final File result = new File("E:/myFile/test.zip");
List<String> urls = new ArrayList<String>();
urls.add("C:\\Users\\Administrator\\Desktop\\test\\000001 (1).exe");
urls.add("C:\\Users\\Administrator\\Desktop\\test\\000001 (1) - 副本.exe");
urls.add("C:\\Users\\Administrator\\Desktop\\test\\000001 (2) - 副本.exe");
urls.add("C:\\Users\\Administrator\\Desktop\\test\\000001 (3) - 副本.exe");
new HighEffiCompressZipTest().createZipFile(urls, result);
long end = System.currentTimeMillis();
System.out.println("用时：" + (end - begin) + " ms");
System.out.println(new Date());
}
class CustomInputStreamSupplier implements InputStreamSupplier {
private File currentFile;
public CustomInputStreamSupplier(File currentFile) {
this.currentFile = currentFile;
}
@Override
public InputStream get() {
try {
// InputStreamSupplier api says:
// 返回值：输入流。永远不能为Null,但可以是一个空的流
return currentFile.isDirectory() ? new NullInputStream(0) : new FileInputStream(currentFile);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
return null;
}
}
private void addEntry(String entryName, File currentFile, HighEffiCompressZip scatterSample) throws IOException {
ZipArchiveEntry archiveEntry = new ZipArchiveEntry(entryName);
archiveEntry.setMethod(ZipEntry.DEFLATED);
final InputStreamSupplier supp = new CustomInputStreamSupplier(currentFile);
scatterSample.addEntry(archiveEntry, supp);
}
private void compressCurrentDirectory(List<String> dir, HighEffiCompressZip scatterSample) throws IOException {
if (dir == null) {
throw new IOException("源路径不能为空！");
}
String relativePath = "";
// // if (dir.isFile()) {
// // relativePath = dir.getName();
// addEntry("download", null, scatterSample);
// return;
// }
// // 空文件夹
// if (dir.listFiles().length == 0) {
// relativePath = dir.getAbsolutePath().replace(scatterSample.getRootPath(), "");
// addEntry(relativePath + File.separator, dir, scatterSample);
// return;
// }
for (String file : dir) {
File f = new File(file);
if (!f.isDirectory()){
relativePath = f.getParent().replace(scatterSample.getRootPaths(), "");
addEntry(relativePath + File.separator + f.getName(), f, scatterSample);
}
}
}
public void createZipFile(final List<String> rootPaths, final File result) throws Exception {
File dstFolder = new File(result.getParent());
if (!dstFolder.isDirectory()) {
dstFolder.mkdirs();
}
final HighEffiCompressZip scatterSample = new HighEffiCompressZip("zip");
compressCurrentDirectory(rootPaths, scatterSample);
final ZipArchiveOutputStream zipArchiveOutputStream = new ZipArchiveOutputStream(result);
scatterSample.writeTo(zipArchiveOutputStream);
zipArchiveOutputStream.close();
}
}
public class HighEffiCompressZip {
private String rootPaths;
ParallelScatterZipCreator scatterZipCreator = new ParallelScatterZipCreator();
// ParallelScatterZipCreator api says:
// 注意这个类不保证写入到输出文件的顺序。需要保持特定顺序的（manifests，文件夹）必须使用这个类的客户类进行处理
// 通常的做法是 在调用这个类的writeTo方法前把这些东西写入到ZipArchiveOutputStream
ScatterZipOutputStream dirs = ScatterZipOutputStream
.fileBased(File.createTempFile("whatever-preffix", ".whatever"));
public HighEffiCompressZip(String rootPaths) throws IOException {
this.rootPaths = rootPaths;
}
public HighEffiCompressZip() throws IOException {
}
public void addEntry(final ZipArchiveEntry zipArchiveEntry, final InputStreamSupplier streamSupplier)
throws IOException {
if (zipArchiveEntry.isDirectory() && !zipArchiveEntry.isUnixSymlink()) {
dirs.addArchiveEntry(ZipArchiveEntryRequest.createZipArchiveEntryRequest(zipArchiveEntry, streamSupplier));
} else {
scatterZipCreator.addArchiveEntry(zipArchiveEntry, streamSupplier);
}
}
public void writeTo(final ZipArchiveOutputStream zipArchiveOutputStream)
throws IOException, ExecutionException, InterruptedException {
dirs.writeTo(zipArchiveOutputStream);
dirs.close();
scatterZipCreator.writeTo(zipArchiveOutputStream);
}
public String getRootPaths() {
return rootPaths;
}
public void setRootPaths(String rootPath) {
this.rootPaths = rootPaths;
}
}
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