android编程之xml文件读取和写入方法

<?xml version="1.0" encoding="UTF-8" standalone="true"?> -<config> <title>远程视频会见系统</title> <local_port>12600</local_port> <schedule_service_ip>10.58.1.59</schedule_service_ip><schedule_service_port>12601</schedule_service_port> </config>

package com.example.helloanychat; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.StringWriter; import java.net.Inet6Address; import java.net.InetAddress; import java.net.NetworkInterface; import java.net.SocketException; import java.util.Enumeration; import javax.xml.parsers.DocumentBuilder; import javax.xml.parsers.DocumentBuilderFactory; import android.os.Environment; import android.util.Log; import org.w3c.dom.Document; import org.w3c.dom.Element; import org.w3c.dom.NodeList; import org.xmlpull.v1.XmlPullParserFactory; import org.xmlpull.v1.XmlSerializer; /**  * 配置信息类  * 新建日期:2014/12/8 by jdh  */ public class Config implements IF_Config {  //配置信息  private Config_Info config_info = new Config_Info();  /**   * 构造函数   */  public Config() {   boolean ok;   File sd_path;   File file_cfg_dir;   File file_cfg;   FileOutputStream out;   String str;   FileInputStream in;   //得到本机ip地址   config_info.local_ip = getLocalIpAddress();   System.out.printf("本机ip:%s/n", config_info.local_ip);   //获取SD卡目录   sd_path = Environment.getExternalStorageDirectory();   //判断文件夹是否存在   file_cfg_dir = new File(sd_path.getPath() + "//Remote_Meeting");  if (!file_cfg_dir.exists() && !file_cfg_dir.isDirectory()) {    System.out.println("配置文件夹Remote_Meeting不存在!");    ok = file_cfg_dir.mkdirs();    if (ok) {     System.out.println("创建文件夹成功!");    } else {     System.out.println("创建文件夹失败!");         }   }   //判断配置文件是否存在   file_cfg = new File(file_cfg_dir.getPath(),"cfg.xml");  if (!file_cfg.exists())   {    System.out.println("配置文件cfg.xml不存在!");   try {     file_cfg.createNewFile();     System.out.println("创建文件cfg.xml成功!");    //生成初始化的配置数据     try {      out = new FileOutputStream(file_cfg);     //保存默认配置      config_info.title = "远程视频会见系统";     config_info.local_port = 12600;      config_info.schedule_server_ip = "10.58.1.59";     config_info.schedule_server_port = 12601;     str = produce_xml_string(config_info);     out.write(str.getBytes());      out.close();     } catch (IOException e) {      // TODO Auto-generated catch block     e.printStackTrace();     }    } catch (IOException e) {     // TODO Auto-generated catch block    e.printStackTrace();    }   }   config_info.title = "远程";   config_info.local_port = 126;   config_info.schedule_server_ip = "10.5";  config_info.schedule_server_port = 12;  System.out.printf("----222222222%s,%d,%s,%d/n",config_info.title,config_info.local_port,  config_info.schedule_server_ip,config_info.schedule_server_port);  //解析xml文件  try {   in = new FileInputStream(file_cfg);   DocumentBuilderFactory factory = DocumentBuilderFactory.newInstance();    DocumentBuilder builder = factory.newDocumentBuilder();   Document document = builder.parse(in);   // 获取根节点    Element root = document.getDocumentElement();   NodeList node = root.getChildNodes();    //获得第1子节点:标题    config_info.title = node.item(0).getFirstChild().getNodeValue();    //获得第2子节点:本机端口    config_info.local_port = Integer.parseInt(node.item(1).getFirstChild().getNodeValue());   //获得第3子节点:调度服务器ip    config_info.schedule_server_ip = node.item(2).getFirstChild().getNodeValue();    //获得第4子节点:调度服务器端口    config_info.schedule_server_port = Integer.parseInt(node.item(3).getFirstChild().getNodeValue());     System.out.printf("----222222222%s,%d,%s,%d/n",config_info.title,config_info.local_port,      config_info.schedule_server_ip,config_info.schedule_server_port);   } catch (Exception e) {    e.printStackTrace();   }  }  @Override  public Config_Info get_config_info() {   return config_info;  }  /**   * 得到本机ip地址   * @return 本机ip地址   */  private String getLocalIpAddress() {   try {    for (Enumeration<NetworkInterface> en = NetworkInterface      .getNetworkInterfaces(); en.hasMoreElements();) {     NetworkInterface intf = en.nextElement();     for (Enumeration<InetAddress> enumIpAddr = intf       .getInetAddresses(); enumIpAddr.hasMoreElements();) {      InetAddress inetAddress = enumIpAddr.nextElement();      //if (!inetAddress.isLoopbackAddress()) {       if (!inetAddress.isLoopbackAddress() && !(inetAddress instanceof Inet6Address)) {       return inetAddress.getHostAddress().toString();      }     }    }   } catch (SocketException ex) {    Log.e("WifiPreference IpAddress", ex.toString());   }   return null;  }  /**   * 生成xml配置文件的String数据流   * Config_Info的本机ip信息不会保存   * @param info:配置信息   * @return xml的String数据流   */  private String produce_xml_string(Config_Info info) {   StringWriter stringWriter = new StringWriter();   try {    // 获取XmlSerializer对象    XmlPullParserFactory factory = XmlPullParserFactory.newInstance();    XmlSerializer xmlSerializer = factory.newSerializer();    // 设置输出流对象    xmlSerializer.setOutput(stringWriter);    //开始标签    xmlSerializer.startDocument("utf-8", true);    xmlSerializer.startTag(null, "config");    //标题    xmlSerializer.startTag(null, "title");    xmlSerializer.text(info.title);    xmlSerializer.endTag(null, "title");    //本机端口    xmlSerializer.startTag(null, "local_port");    xmlSerializer.text(Integer.toString(info.local_port));    xmlSerializer.endTag(null, "local_port");    //调度服务器ip    xmlSerializer.startTag(null, "schedule_service_ip");    xmlSerializer.text(info.schedule_server_ip);    xmlSerializer.endTag(null, "schedule_service_ip");    //调度服务器端口    xmlSerializer.startTag(null, "schedule_service_port");    xmlSerializer.text(Integer.toString(info.schedule_server_port));    xmlSerializer.endTag(null, "schedule_service_port");    xmlSerializer.endTag(null, "config");    xmlSerializer.endDocument();   } catch (Exception e) {    e.printStackTrace();   }   return stringWriter.toString();  } }