public static void createFile(File file) throws IOException {
    if (file.exists()) {
      return;
    }
    File parentFile = file.getParentFile();
    if (!parentFile.exists())
      parentFile.mkdirs();
    file.createNewFile();
  }

  public static void unzip(File archive, File output) throws IOException {
    byte[] buffer = new byte[1500];
    if (!output.exists()) {
      output.mkdir();
    }
    ZipInputStream zis = new ZipInputStream(new BufferedInputStream(new FileInputStream(archive)));
    ZipEntry ze;
    while ((ze = zis.getNextEntry()) != null) {
      File newFile = new File(output, ze.getName());
      if (!ze.isDirectory()) {
        createFile(newFile);
        BufferedOutputStream fos = new BufferedOutputStream(new FileOutputStream(newFile));
        int len;
        while ((len = zis.read(buffer)) > 0)
          fos.write(buffer, 0, len);
        fos.close();
      }
    }
    zis.close();
  }