dom4j对文件的读写 生成xml文件用于 记录 同步时间

public class DataOutputTimeXml {
//文件保存到xml文件
public  void saveExportDateToXml(String loginname)
{
    try {
            XMLWriter writer = null;// 声明写XML的对象
            SAXReader reader = new SAXReader();
            OutputFormat format = OutputFormat.createPrettyPrint();
            format.setEncoding("utf-8");// 设置XML文件的编码格式
            String path= System.getProperty("user.dir");//???E:\neweclipsewprkspace\toponymcensus
            String filePath = path+"//app"+"//datefile"+"//"+"date.xml";
            //String filePath ="E://lxh.xml";
            File file = new File(filePath);
            if (file.exists()) {
                Document document = reader.read(file);// 读取XML文件
                Element root = document.getRootElement();// 得到根节点
                boolean bl = true;
                for (Iterator i = root.elementIterator("info"); i.hasNext();) {
                    Element info = (Element) i.next();
                    if (info.element("name").getTextTrim()!=null && loginname.equals(info.element("name").getTextTrim())) {
                        // 修改导出时间
                    info.element("date").setText(DateUtil.dateToString(new Date(), "yy-MM-dd HH:mm:ss"));
                        writer = new XMLWriter(new FileWriter(filePath), format);
                        writer.write(document);
                        writer.close();
                        bl = false;
                        break;
                    }
                 
                }
                if (bl) {
                    // 添加一个信息
                    Element info = root.addElement("info");
                    Element name = info.addElement("name");
                    name.setText(loginname);
                    Element date = info.addElement("date");
                    date.setText(DateUtil.dateToString(new Date(), "yy-MM-dd HH:mm:ss"));
                    writer = new XMLWriter(new FileWriter(filePath), format);
                    writer.write(document);
                    writer.close();
                }
            } else {
                // 新建.xml文件并新增内容
                Document _document = DocumentHelper.createDocument();
                Element _root = _document.addElement("Doucument");
                Element _info = _root.addElement("info");
                Element _username = _info.addElement("name");
                _username.setText(loginname);
                Element _date = _info.addElement("date");
                _date.setText(DateUtil.dateToString(new Date(), "yy-MM-dd HH:mm:ss"));
                writer = new XMLWriter(new FileWriter(file), format);
                writer.write(_document);
                writer.close();
            }
            System.out.println("操作结束! ");
        } catch (Exception e) {
            e.printStackTrace();
        }

    }
/**
* 根据用户名得到上次时间
* @param loginname
* @return
*/
//解析.xml文件
public String getDateByLoginName(String loginname)
{
String returnDate ="";
try{

           SAXReader reader = new SAXReader();
   String path= System.getProperty("user.dir");//???E:\neweclipsewprkspace\toponymcensus
           String filePath = path+"//app"+"//datefile"+"//"+"date.xml";
           //String filePath ="E://lxh.xml";
           File file = new File(filePath);
           if (file.exists()) {
               Document document = reader.read(file);// 读取XML文件
               Element root = document.getRootElement();// 得到根节点
               boolean bl = true;
               for (Iterator i = root.elementIterator("info"); i.hasNext();) {
                   Element info = (Element) i.next();
                   if (info.element("name").getTextTrim()!=null && loginname.equals(info.element("name").getTextTrim())) {
                   returnDate = info.element("date").getTextTrim();
                   }
                
               }
           }
           return returnDate;
}catch(Exception e)
{
e.printStackTrace();
return null;

}


}

}