解析xml乱码

dom4j针对xml乱码：
OutputFormat format = OutputFormat.createPrettyPrint();
format.setEncoding("UTF-8"/"gb2312");
XMLWriter writer = new XMLWriter(new FileOutputStream(url),format);----字节流处理最好

注意：XMLWriter writer = new XMLWriter（new FileWriter(url)）可能乱码。----字符流不查码表（默认gb312）