Comment créer un fichier zip en Java

Question

J'ai un fichier texte dynamique qui extrait le contenu d'une base de données en fonction de la requête de l'utilisateur. Je dois écrire ce contenu dans un fichier texte et le zipper dans un dossier dans une servlet. Comment dois-je m'y prendre ?

Answer 1

Comme il m'a fallu un certain temps pour trouver la solution, j'ai pensé qu'il serait utile de publier ma solution en utilisant Java 7+ ZipFileSystem.

 openZip(runFile);

 addToZip(filepath); //loop construct;  

 zipfs.close();

 private void openZip(File runFile) throws IOException {
    Map<String, String> env = new HashMap<>();
    env.put("create", "true");
    env.put("encoding", "UTF-8");
    Files.deleteIfExists(runFile.toPath());
    zipfs = FileSystems.newFileSystem(URI.create("jar:" + runFile.toURI().toString()), env);    
 }

 private void addToZip(String filename) throws IOException {
    Path externalTxtFile = Paths.get(filename).toAbsolutePath();
    Path pathInZipfile = zipfs.getPath(filename.substring(filename.lastIndexOf("results"))); //all files to be stored have a common base folder, results/ in my case
    if (Files.isDirectory(externalTxtFile)) {
        Files.createDirectories(pathInZipfile);
        try (DirectoryStream<Path> ds = Files.newDirectoryStream(externalTxtFile)) {
            for (Path child : ds) {
                addToZip(child.normalize().toString()); //recursive call
            }
        }
    } else {
        // copy file to zip file
        Files.copy(externalTxtFile, pathInZipfile, StandardCopyOption.REPLACE_EXISTING);            
    }
 }

Answer 2

public static void zipFromTxt(String zipFilePath, String txtFilePath) {
    Assert.notNull(zipFilePath, "Zip file path is required");
    Assert.notNull(txtFilePath, "Txt file path is required");
    zipFromTxt(new File(zipFilePath), new File(txtFilePath));
}

public static void zipFromTxt(File zipFile, File txtFile) {
    ZipOutputStream out = null;
    FileInputStream in = null;
    try {
        Assert.notNull(zipFile, "Zip file is required");
        Assert.notNull(txtFile, "Txt file is required");
        out = new ZipOutputStream(new FileOutputStream(zipFile));
        in = new FileInputStream(txtFile);
        out.putNextEntry(new ZipEntry(txtFile.getName()));
        int len;
        byte[] buffer = new byte[1024];
        while ((len = in.read(buffer)) > 0) {
            out.write(buffer, 0, len);
            out.flush();
        }
    } catch (Exception e) {
        log.info("Zip from txt occur error,Detail message:{}", e.toString());
    } finally {
        try {
            if (in != null) in.close();
            if (out != null) {
                out.closeEntry();
                out.close();
            }
        } catch (Exception e) {
            log.info("Zip from txt close error,Detail message:{}", e.toString());
        }
    }
}

Answer 3

Utilisation de Jeka https://jeka.dev JkPathTree, c'est assez simple.

Path wholeDirToZip = Paths.get("dir/to/zip");
Path zipFile = Paths.get("file.zip");
JkPathTree.of(wholeDirToZip).zipTo(zipFile);