code: private static ZipOutputStream getZipOutputStream(OutputStream out, Charset charset) {
  		charset = (null == charset) ? DEFAULT_CHARSET : charset;
  		return new ZipOutputStream(out, charset);
  	}
docs: 获得 {@link ZipOutputStream}
  
  @param zipFile 压缩文件
  @param charset 编码
  @return {@link ZipOutputStream}