Android学习笔记（十三）-使用Socket进行大文件断点上传续传

　　在Android中上传文件可以采用HTTP方式，也可以采用Socket方式，但是HTTP方式不能上传大文件，这里介绍一种通过Socket方式来进行断点续传的方式，服务端会记录下文件的上传进度，当某一次上传过程意外终止后，下一次可以继续上传，这里用到的其实还是J2SE里的知识。

　　这个上传程序的原理是：客户端第一次上传时向服务端发送“Content-Length=35;filename=WinRAR_3.90_SC.exe;sourceid=“这种格式的字符串，服务端收到后会查找该文件是否有上传记录，如果有就返回已经上传的位置，否则返回新生成的sourceid以及position为0，类似”sourceid=2324838389;position=0“这样的字符串，客户端收到返回后的字符串后再从指定的位置开始上传文件。

首先是服务端代码：

SocketServer.java

package com.android.socket.server; import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.OutputStream; import java.io.PushbackInputStream; import java.io.RandomAccessFile; import java.net.ServerSocket; import java.net.Socket; import java.text.SimpleDateFormat; import java.util.Date; import java.util.HashMap; import java.util.Map; import java.util.Properties; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import com.android.socket.utils.StreamTool; public class SocketServer { private ExecutorService executorService;// 线程池 private ServerSocket ss = null; private int port;// 监听端口 private boolean quit;// 是否退出 private Map datas = new HashMap();// 存放断点数据，最好改为数据库存放 public SocketServer(int port) { this.port = port; // 初始化线程池 executorService = Executors.newFixedThreadPool(Runtime.getRuntime() .availableProcessors() * 50); } // 启动服务 public void start() throws Exception { ss = new ServerSocket(port); while (!quit) { Socket socket = ss.accept();// 接受客户端的请求 // 为支持多用户并发访问，采用线程池管理每一个用户的连接请求 executorService.execute(new SocketTask(socket));// 启动一个线程来处理请求 } } // 退出 public void quit() { this.quit = true; try { ss.close(); } catch (IOException e) { e.printStackTrace(); } } public static void main(String[] args) throws Exception { SocketServer server = new SocketServer(8787); server.start(); } private class SocketTask implements Runnable { private Socket socket; public SocketTask(Socket socket) { this.socket = socket; } @Override public void run() { try { System.out.println("accepted connenction from " + socket.getInetAddress() + " @ " + socket.getPort()); PushbackInputStream inStream = new PushbackInputStream( socket.getInputStream()); // 得到客户端发来的第一行协议数据：Content-Length=143253434;filename=xxx.3gp;sourceid= // 如果用户初次上传文件，sourceid的值为空。 String head = StreamTool.readLine(inStream); System.out.println(head); if (head != null) { // 下面从协议数据中读取各种参数值 String[] items = head.split(";"); String filelength = items[0].substring(items[0].indexOf("=") + 1); String filename = items[1].substring(items[1].indexOf("=") + 1); String sourceid = items[2].substring(items[2].indexOf("=") + 1); Long id = System.currentTimeMillis(); FileLog log = null; if (null != sourceid && !"".equals(sourceid)) { id = Long.valueOf(sourceid); log = find(id);//查找上传的文件是否存在上传记录 } File file = null; int position = 0; if(log==null){//如果上传的文件不存在上传记录,为文件添加跟踪记录 String path = new SimpleDateFormat("yyyy/MM/dd/HH/mm").format(new Date()); File dir = new File("file/"+ path); if(!dir.exists()) dir.mkdirs(); file = new File(dir, filename); if(file.exists()){//如果上传的文件发生重名，然后进行改名 filename = filename.substring(0, filename.indexOf(".")-1)+ dir.listFiles().length+ filename.substring(filename.indexOf(".")); file = new File(dir, filename); } save(id, file); }else{// 如果上传的文件存在上传记录,读取上次的断点位置 file = new File(log.getPath());//从上传记录中得到文件的路径 if(file.exists()){ File logFile = new File(file.getParentFile(), file.getName()+".log"); if(logFile.exists()){ Properties properties = new Properties(); properties.load(new FileInputStream(logFile)); position = Integer.valueOf(properties.getProperty("length"));//读取断点位置 } } } OutputStream outStream = socket.getOutputStream(); String response = "sourceid="+ id+ ";position="+ position+ "\r\n"; //服务器收到客户端的请求信息后，给客户端返回响应信息：sourceid=1274773833264;position=0 //sourceid由服务生成，唯一标识上传的文件，position指示客户端从文件的什么位置开始上传 outStream.write(response.getBytes()); RandomAccessFile fileOutStream = new RandomAccessFile(file, "rwd"); if(position==0) fileOutStream.setLength(Integer.valueOf(filelength));//设置文件长度 fileOutStream.seek(position);//移动文件指定的位置开始写入数据 byte[] buffer = new byte[1024]; int len = -1; int length = position; while( (len=inStream.read(buffer)) != -1){//从输入流中读取数据写入到文件中 fileOutStream.write(buffer, 0, len); length += len; Properties properties = new Properties(); properties.put("length", String.valueOf(length)); FileOutputStream logFile = new FileOutputStream(new File(file.getParentFile(), file.getName()+".log")); properties.store(logFile, null);//实时记录文件的最后保存位置 logFile.close(); } if(length==fileOutStream.length()) delete(id); fileOutStream.close(); inStream.close(); outStream.close(); file = null; } } catch (Exception e) { e.printStackTrace(); } finally { try { if(socket != null && !socket.isClosed()) socket.close(); } catch (IOException e) {} } } } public FileLog find(Long sourceid) { return datas.get(sourceid); } // 保存上传记录 public void save(Long id, File saveFile) { // 日后可以改成通过数据库存放 datas.put(id, new FileLog(id, saveFile.getAbsolutePath())); } // 当文件上传完毕，删除记录 public void delete(long sourceid) { if (datas.containsKey(sourceid)) datas.remove(sourceid); } private class FileLog { private Long id; private String path; public FileLog(Long id, String path) { super(); this.id = id; this.path = path; } public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getPath() { return path; } public void setPath(String path) { this.path = path; } } }

ServerWindow.java

package com.android.socket.server; import java.awt.BorderLayout; import java.awt.Frame; import java.awt.Label; import java.awt.event.WindowEvent; import java.awt.event.WindowListener; public class ServerWindow extends Frame{ private SocketServer server; private Label label; public ServerWindow(String title){ super(title); server = new SocketServer(8787); label = new Label(); add(label, BorderLayout.PAGE_START); label.setText("服务器已经启动"); this.addWindowListener(new WindowListener() { @Override public void windowOpened(WindowEvent e) { new Thread(new Runnable() { @Override public void run() { try { server.start(); } catch (Exception e) { e.printStackTrace(); } } }).start(); } @Override public void windowIconified(WindowEvent e) { } @Override public void windowDeiconified(WindowEvent e) { } @Override public void windowDeactivated(WindowEvent e) { } @Override public void windowClosing(WindowEvent e) { server.quit(); System.exit(0); } @Override public void windowClosed(WindowEvent e) { } @Override public void windowActivated(WindowEvent e) { } }); } /** * @param args */ public static void main(String[] args) { ServerWindow window = new ServerWindow("文件上传服务端"); window.setSize(300, 300); window.setVisible(true); } }
工具类StreamTool.java

package com.android.socket.utils; import java.io.ByteArrayOutputStream; import java.io.File; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; import java.io.PushbackInputStream; public class StreamTool { public static void save(File file, byte[] data) throws Exception { FileOutputStream outStream = new FileOutputStream(file); outStream.write(data); outStream.close(); } public static String readLine(PushbackInputStream in) throws IOException { char buf[] = new char[128]; int room = buf.length; int offset = 0; int c; loop: while (true) { switch (c = in.read()) { case -1: case '\n': break loop; case '\r': int c2 = in.read(); if ((c2 != '\n') && (c2 != -1)) in.unread(c2); break loop; default: if (--room < 0) { char[] lineBuffer = buf; buf = new char[offset + 128]; room = buf.length - offset - 1; System.arraycopy(lineBuffer, 0, buf, 0, offset); } buf[offset++] = (char) c; break; } } if ((c == -1) && (offset == 0)) return null; return String.copyValueOf(buf, 0, offset); } /** * 读取流 * @param inStream * @return 字节数组 * @throws Exception */ public static byte[] readStream(InputStream inStream) throws Exception{ ByteArrayOutputStream outSteam = new ByteArrayOutputStream(); byte[] buffer = new byte[1024]; int len = -1; while( (len=inStream.read(buffer)) != -1){ outSteam.write(buffer, 0, len); } outSteam.close(); inStream.close(); return outSteam.toByteArray(); } }
Android客户端代码：

布局文件layout/main.xml

数据文件values/strings.xml

Hello World, UploadActivity! 大视频文件断点上传 文件名称 上传 SDCard不存在或者写保护 上传完成 上传失败 文件不存在
AndroidManifest.xml

UploadActivity.java

package com.android.upload; import java.io.File; import java.io.OutputStream; import java.io.PushbackInputStream; import java.io.RandomAccessFile; import java.net.Socket; import android.app.Activity; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.os.Message; import android.view.View; import android.widget.Button; import android.widget.EditText; import android.widget.ProgressBar; import android.widget.TextView; import android.widget.Toast; import com.android.service.UploadLogService; import com.android.utils.StreamTool; public class UploadActivity extends Activity { private EditText filenameText; private TextView resulView; private ProgressBar uploadbar; private UploadLogService logService; private Handler handler = new Handler(){ @Override public void handleMessage(Message msg) { int length = msg.getData().getInt("size"); uploadbar.setProgress(length); float num = (float)uploadbar.getProgress()/(float)uploadbar.getMax(); int result = (int)(num * 100); resulView.setText(result+ "%"); if(uploadbar.getProgress()==uploadbar.getMax()){ Toast.makeText(UploadActivity.this, R.string.success, 1).show(); } } }; @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.main); logService = new UploadLogService(this); filenameText = (EditText)this.findViewById(R.id.filename); uploadbar = (ProgressBar) this.findViewById(R.id.uploadbar); resulView = (TextView)this.findViewById(R.id.result); Button button =(Button)this.findViewById(R.id.button); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { String filename = filenameText.getText().toString(); if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){ File uploadFile = new File(Environment.getExternalStorageDirectory(), filename); if(uploadFile.exists()){ uploadFile(uploadFile); }else{ Toast.makeText(UploadActivity.this, R.string.filenotexsit, 1).show(); } }else{ Toast.makeText(UploadActivity.this, R.string.sdcarderror, 1).show(); } } }); } /** * 上传文件 * @param uploadFile */ private void uploadFile(final File uploadFile) { new Thread(new Runnable() { @Override public void run() { try { uploadbar.setMax((int)uploadFile.length()); String souceid = logService.getBindId(uploadFile); String head = "Content-Length="+ uploadFile.length() + ";filename="+ uploadFile.getName() + ";sourceid="+ (souceid==null? "" : souceid)+"\r\n"; Socket socket = new Socket("192.168.1.123", 8787); OutputStream outStream = socket.getOutputStream(); outStream.write(head.getBytes()); PushbackInputStream inStream = new PushbackInputStream(socket.getInputStream()); String response = StreamTool.readLine(inStream); String[] items = response.split(";"); String responseid = items[0].substring(items[0].indexOf("=")+1); String position = items[1].substring(items[1].indexOf("=")+1); if(souceid==null){//代表原来没有上传过此文件，往数据库添加一条绑定记录 logService.save(responseid, uploadFile); } RandomAccessFile fileOutStream = new RandomAccessFile(uploadFile, "r"); fileOutStream.seek(Integer.valueOf(position)); byte[] buffer = new byte[1024]; int len = -1; int length = Integer.valueOf(position); while( (len = fileOutStream.read(buffer)) != -1){ outStream.write(buffer, 0, len); length += len; Message msg = new Message(); msg.getData().putInt("size", length); handler.sendMessage(msg); } fileOutStream.close(); outStream.close(); inStream.close(); socket.close(); if(length==uploadFile.length()) logService.delete(uploadFile); } catch (Exception e) { e.printStackTrace(); } } }).start(); } }
UploadLogService.java

package com.android.service; import java.io.File; import android.content.Context; import android.database.Cursor; import android.database.sqlite.SQLiteDatabase; public class UploadLogService { private DBOpenHelper dbOpenHelper; public UploadLogService(Context context){ this.dbOpenHelper = new DBOpenHelper(context); } public void save(String sourceid, File uploadFile){ SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); db.execSQL("insert into uploadlog(uploadfilepath, sourceid) values(?,?)", new Object[]{uploadFile.getAbsolutePath(),sourceid}); } public void delete(File uploadFile){ SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); db.execSQL("delete from uploadlog where uploadfilepath=?", new Object[]{uploadFile.getAbsolutePath()}); } public String getBindId(File uploadFile){ SQLiteDatabase db = dbOpenHelper.getReadableDatabase(); Cursor cursor = db.rawQuery("select sourceid from uploadlog where uploadfilepath=?", new String[]{uploadFile.getAbsolutePath()}); if(cursor.moveToFirst()){ return cursor.getString(0); } return null; } }
DBOpenHelper.java

package com.android.service; import android.content.Context; import android.database.sqlite.SQLiteDatabase; import android.database.sqlite.SQLiteOpenHelper; public class DBOpenHelper extends SQLiteOpenHelper { public DBOpenHelper(Context context) { super(context, "upload.db", null, 1); } @Override public void onCreate(SQLiteDatabase db) { db.execSQL("CREATE TABLE uploadlog (_id integer primary key autoincrement, uploadfilepath varchar(100), sourceid varchar(10))"); } @Override public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) { db.execSQL("DROP TABLE IF EXISTS uploadlog"); onCreate(db); } }
StreamTool.java上面已经给出过了。