用SAX读写XML文件

今天的项目里做了一个缓存文件 利用的就是xml
读都好说 其实写也很简单 机械化了一点 不过都是必要的

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.OutputStream;
import java.io.StringReader;
import java.io.StringWriter;
import java.util.ArrayList;

import javax.xml.parsers.ParserConfigurationException;
import javax.xml.parsers.SAXParser;
import javax.xml.parsers.SAXParserFactory;

import org.xml.sax.Attributes;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
import org.xml.sax.XMLReader;
import org.xml.sax.helpers.DefaultHandler;
import org.xmlpull.v1.XmlSerializer;



import android.util.Xml;

import com.yolove.player.entity.AudioInfo;

public class PlaylistSyncUtil {
	public static ArrayList<AudioInfo> list;
	
	public PlaylistSyncUtil(){
		
	}
	public static void savetoLocal(ArrayList<AudioInfo> audiolist,String path){
		//取得文件名
		String name=path.substring(path.lastIndexOf("/")+1, path.lastIndexOf("."));
		//得到xml序列化工具
		XmlSerializer serializer=Xml.newSerializer();
		//生成Stringwriter对象
		StringWriter writer=new StringWriter();
		if(audiolist.size()>0){
			try {
				serializer.setOutput(writer);
				//XML文件头
				serializer.startDocument("UTF-8", true);
				/*
				 * 开始xml文件主体的构建
				 * xml的根root为playlist
				 * 次级根为audioInfo 标识每一个单独的audioinfo对象
				 * 对象中的属性以<></>的格式进行存储
				 */
				//<playlist>
				serializer.startTag("", "playlist");
				for(int i=0;i<audiolist.size();i++){
					AudioInfo info=audiolist.get(i);
					serializer.startTag("", "AudioInfo");
					
					serializer.startTag("", "id");
					serializer.text(info.getId()+"");
					serializer.endTag("", "id");
					
					serializer.startTag("", "data");
					serializer.text(info.getData()+"");
					serializer.endTag("", "data");
					
					serializer.startTag("", "displayname");
					serializer.text(info.getDisplayName()+"");
					serializer.endTag("", "displayname");
					
					serializer.startTag("", "size");
					serializer.text(info.getSize()+"");
					serializer.endTag("", "size");
					
					serializer.startTag("", "dateAdded");
					serializer.text(info.getDateAdded()+"");
					serializer.endTag("", "dateAdded");
					
					serializer.startTag("", "dateModified");
					serializer.text(info.getDateModified()+"");
					serializer.endTag("", "dateModified");
					
					serializer.startTag("", "title");
					serializer.text(info.getTitle()+"");
					serializer.endTag("", "title");
					
					serializer.startTag("", "duration");
					serializer.text(info.getDuration()+"");
					serializer.endTag("", "duration");
					
					serializer.startTag("", "artistId");
					serializer.text(info.getArtistId()+"");
					serializer.endTag("", "artistId");
					
					serializer.startTag("", "albumId");
					serializer.text(info.getAlbumId()+"");
					serializer.endTag("", "albumId");
					
					serializer.startTag("", "year");
					serializer.text(info.getYear()+"");
					serializer.endTag("", "year");
					
					serializer.startTag("", "bookmark");
					serializer.text(info.getBookMark()+"");
					serializer.endTag("", "bookmark");
					
					serializer.startTag("", "lrcData");
					serializer.text(info.getLrcData()+"");
					serializer.endTag("", "lrcData");
					
					serializer.startTag("", "picData");
					serializer.text(info.getPicData()+"");
					serializer.endTag("", "picData");
					
					serializer.startTag("", "album");
					serializer.text(info.getAlbum()+"");
					serializer.endTag("", "album");
					
					serializer.startTag("", "artist");
					serializer.text(info.getArtist()+"");
					serializer.endTag("", "artist");
					
					serializer.startTag("", "lpDownOnce");
					serializer.text(info.isLpDownOnce()+"");
					serializer.endTag("", "lpDownOnce");
					
					serializer.startTag("", "uuid");
					serializer.text(info.getUuid()+"");
					serializer.endTag("", "uuid");
					
					serializer.startTag("", "type");
					serializer.text(info.getType()+"");
					serializer.endTag("", "type");
					
					serializer.startTag("", "smallpicurl");
					serializer.text(info.getSmallpicurl()+"");
					serializer.endTag("", "smallpicurl");
					
					serializer.startTag("", "bigpicurl");
					serializer.text(info.getBigpicurl()+"");
					serializer.endTag("", "bigpicurl");
					
					serializer.startTag("", "description");
					serializer.text(info.getDescription()+"");
					serializer.endTag("", "description");
					
					serializer.startTag("", "isplaying");
					serializer.text(info.isPlaying()+"");
					serializer.endTag("", "isplaying");
					
					serializer.startTag("", "isselected");
					serializer.text(info.isSelected()+"");
					serializer.endTag("", "isselected");
					
					serializer.endTag("", "AudioInfo");
				}
				serializer.endTag("", "playlist");
				serializer.endDocument();
		}catch (IllegalArgumentException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IllegalStateException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		
		
			//结果字符串
//			writer.toString();
		 boolean flag = true; 
         BufferedReader bufferedReader = null; 
         BufferedWriter bufferedWriter = null; 
         try { 
                 File distFile = new File(path);
                 if(distFile.exists()){
                	 distFile.delete();
                 }
                 bufferedReader = new BufferedReader(new StringReader(writer.toString())); 
                 bufferedWriter = new BufferedWriter(new FileWriter(distFile)); 
                 char buf[] = new char[1024];         //字符缓冲区 
                 int len; 
                 while ((len = bufferedReader.read(buf)) != -1) { 
                         bufferedWriter.write(buf, 0, len); 
                 } 
                 bufferedWriter.flush(); 
                 bufferedReader.close(); 
                 bufferedWriter.close(); 
         } catch (IOException e) { 
                 e.printStackTrace(); 
                 flag = false; 
         } finally { 
                 if (bufferedReader != null) { 
                         try { 
                                 bufferedReader.close(); 
                         } catch (IOException e) { 
                                 e.printStackTrace(); 
                         } 
                 } 
         } 
		} 
	}
	public static ArrayList<AudioInfo> getAudioListFromLocal(String path){
		SAXParserFactory sax=SAXParserFactory.newInstance();
		PlaylistXMLHandler playlistHandler=new PlaylistXMLHandler();
		try {
			SAXParser parser=sax.newSAXParser();
			XMLReader reader=parser.getXMLReader();
			reader.setContentHandler(playlistHandler);
			reader.parse(new InputSource(new FileInputStream(new File(path))));
		} catch (ParserConfigurationException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (SAXException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (FileNotFoundException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		} catch (IOException e) {
			// TODO Auto-generated catch block
			e.printStackTrace();
		}
		return list;
	}
	
	static class PlaylistXMLHandler extends DefaultHandler {
		String tag;
		AudioInfo info;
		StringBuilder builder=new StringBuilder();
		@Override
		public void characters(char[] ch, int start, int length)
				throws SAXException {
			// TODO Auto-generated method stub
			if(!(tag.equals(""))){
				builder.append(ch,start,length);
			}
			super.characters(ch, start, length);
		}

		@Override
		public void endElement(String uri, String localName, String qName)
				throws SAXException {
			// TODO Auto-generated method stub
			super.endElement(uri, localName, qName);
			if(tag.equals("uuid")){
				info.setUuid(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("artist")){
				info.setArtist(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("id")){
				info.setId(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("size")){
				info.setSize(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("bookmark")){
				info.setBookMark(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			//
			else if(tag.equals("year")){
				info.setYear(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("albumId")){
				info.setAlbumId(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("artistId")){
				info.setArtistId(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("dateAdded")){
				info.setDateAdded(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("dateModified")){
				info.setDateModified(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("title")){
				info.setTitle(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("lpDownOnce")){
				info.setLpDownOnce((builder.toString().replaceAll("\n", "").replaceAll("\\s", "").equals("true")?true:false));
				builder.setLength(0);
			}
			else if(tag.equals("isplaying")){
				info.setPlaying((builder.toString().replaceAll("\n", "").replaceAll("\\s", "").equals("true")?true:false));
				builder.setLength(0);
			}
			else if(tag.equals("isselected")){
				info.setSelected((builder.toString().replaceAll("\n", "").replaceAll("\\s", "").equals("true")?true:false));
				builder.setLength(0);
			}
			else if(tag.equals("artist")){
				info.setArtist(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("songname")){
				info.setTitle(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("album")){
				info.setAlbum(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("duration")){
				info.setDuration(Integer.parseInt(builder.toString().replaceAll("\n", "").replaceAll("\\s", "")));
				builder.setLength(0);
			}
			else if(tag.equals("type")){
				info.setType(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("data")){
				info.setData(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				//System.out.println("url--->"+builder);
				builder.setLength(0);
			}
			else if(tag.equals("smallpicurl")){
				info.setSmallpicurl(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				//System.out.println("smallpicurl--->"+builder);
				builder.setLength(0);
			}
			else if(tag.equals("bigpicurl")){
				info.setBigpicurl(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				//System.out.println("bigpicurl--->"+builder);
				builder.setLength(0);
			}
			else if(tag.equals("lrcData")){
				info.setLrcData(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("picData")){
				info.setPicData(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("description")){
				info.setDescription(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			else if(tag.equals("displayname")){
				info.setDisplayName(builder.toString().replaceAll("\n", "").replaceAll("\\s", ""));
				builder.setLength(0);
			}
			tag="";
			if(localName.equals("AudioInfo")){
				list.add(info);
			}
		}

		@Override
		public void startElement(String uri, String localName, String qName,
				Attributes attributes) throws SAXException {
			// TODO Auto-generated method stub
			super.startElement(uri, localName, qName, attributes);
			tag=localName;
			if(tag.equals("playlist")){
				if(list==null)
				list=new ArrayList<AudioInfo>();
				else{
					list.clear();
				}
			}else if(tag.equals("AudioInfo")){
				info=new AudioInfo();
			}
		}
		
	}
}