code: public static BOMInputStream getBOMInputStream(File file) throws IORuntimeException {
  		try {
  			return new BOMInputStream(new FileInputStream(file));
  		} catch (IOException e) {
  			throw new IORuntimeException(e);
  		}
  	}
docs: 获得BOM输入流，用于处理带BOM头的文件
  
  @param file 文件
  @return 输入流
  @throws IORuntimeException 文件未找到