code: public static boolean unpackEntry(File zip, String name, File file, Charset charset) {
      ZipFile zf = null;
      try {
        if (charset != null) {
          zf = new ZipFile(zip, charset);
        }
        else {
          zf = new ZipFile(zip);
        }
        return doUnpackEntry(zf, name, file);
      }
      catch (IOException e) {
        throw ZipExceptionUtil.rethrow(e);
      }
      finally {
        closeQuietly(zf);
      }
    }
docs: Unpacks a single file from a ZIP archive to a file.
  
  @param zip
  ZIP file.
  @param name
  entry name.
  @param file
  target file to be created or overwritten.
  @param charset
  charset to be used processing the zip
  
  @return <code>true</code> if the entry was found and unpacked,
  <code>false</code> if the entry was not found.