code: public File writeFromStream(InputStream in) throws IORuntimeException {
  		FileOutputStream out = null;
  		try {
  			out = new FileOutputStream(FileUtil.touch(file));
  			IoUtil.copy(in, out);
  		}catch (IOException e) {
  			throw new IORuntimeException(e);
  		} finally {
  			IoUtil.close(out);
  		}
  		return file;
  	}
docs: 将流的内容写入文件<br>
  此方法不会关闭输入流
  
  @param in 输入流，不关闭
  @return dest
  @throws IORuntimeException IO异常