文件已存在

SAXReader saxReader = new SAXReader();//解析器
   OutputFormat outputFormat = OutputFormat.createPrettyPrint();// 设置编码方式
   outputFormat.setEncoding("UTF-8");// 设置编码方式GBK
   FileInputStream fileInputStream = new FileInputStream(file);//
   document = saxReader.read(fileInputStream, "UTF-8");//读入文件