zip/compress a folder full of files on android

Question

I need to zip up a \"project\" folder to allow users to share projects via email. I found a class for zipping up multiple files into one zip, but I need to keep the folder s

Answer 1

I have reworked the code from HailZeon to work properly under windows. Zip Entries must be closed before new ones are started and a starting "/" at entry names like "/file.txt" makes also problems

/**
 * Zips a Folder to "[Folder].zip"
 * @param toZipFolder Folder to be zipped
 * @return the resulting ZipFile
 */
public static File zipFolder(File toZipFolder) {
    File ZipFile = new File(toZipFolder.getParent(), format("%s.zip", toZipFolder.getName()));
    try {
        ZipOutputStream out = new ZipOutputStream(new FileOutputStream(ZipFile));
        zipSubFolder(out, toZipFolder, toZipFolder.getPath().length());
        out.close();
        return ZipFile;
    } catch (Exception ex) {
        ex.printStackTrace();
        return null;
    }
}

/**
 * Main zip Function
 * @param out Target ZipStream
 * @param folder Folder to be zipped
 * @param basePathLength Length of original Folder Path (for recursion)
 */
private static void zipSubFolder(ZipOutputStream out, File folder, int basePathLength) throws IOException {

    final int BUFFER = 2048;

    File[] fileList = folder.listFiles();
    BufferedInputStream origin = null;
    for (File file : fileList) {
        if (file.isDirectory()) {
            zipSubFolder(out, file, basePathLength);
        } else {
            byte data[] = new byte[BUFFER];

            String unmodifiedFilePath = file.getPath();
            String relativePath = unmodifiedFilePath.substring(basePathLength + 1);

            FileInputStream fi = new FileInputStream(unmodifiedFilePath);
            origin = new BufferedInputStream(fi, BUFFER);

            ZipEntry entry = new ZipEntry(relativePath);
            entry.setTime(file.lastModified()); // to keep modification time after unzipping
            out.putNextEntry(entry);

            int count;
            while ((count = origin.read(data, 0, BUFFER)) != -1) {
                out.write(data, 0, count);
            }
            origin.close();
            out.closeEntry();
        }
    }
}