7.6.3 基于TCP协议的Socket通信(2)

本节引言:

上节中我们给大家接触了Socket的一些基本概念以及使用方法,然后写了一个小猪简易聊天室的 Demo,相信大家对Socket有了初步的掌握,本节我们来学习下使用Socket来实现大文件的断点续传! 这里讲解的是别人写好的一个Socket上传大文件的例子,不要求我们自己可以写出来,需要的时候会用 就好!

1.运行效果图:

1.先把我们编写好的Socket服务端运行起来:

2.将一个音频文件放到SD卡根目录下:

3.运行我们的客户端:

4.上传成功后可以看到我们的服务端的项目下生成一个file的文件夹,我们可以在这里找到上传的文件: .log那个是我们的日志文件

2.实现流程图:

3.代码示例:

先编写一个服务端和客户端都会用到的流解析类:

StreamTool.java

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();  }  }

1)服务端的实现:

socket管理与多线程管理类:

FileServer.java

public  class  FileServer  {  private  ExecutorService executorService;//线程池  private  int port;//监听端口  private  boolean quit =  false;//退出  private  ServerSocket server;  private  Map<Long,  FileLog> datas =  new  HashMap<Long,  FileLog>();//存放断点数据  public  FileServer(int port){  this.port = port;  //创建线程池,池中具有(cpu个数*50)条线程 executorService =  Executors.newFixedThreadPool(Runtime.getRuntime().availableProcessors()  *  50);  }  /** 
     * 退出 
     */  public  void quit(){  this.quit =  true;  try  { server.close();  }  catch  (IOException e)  {  }  }  /** 
     * 启动服务 
     * @throws Exception 
     */  public  void start()  throws  Exception{ server =  new  ServerSocket(port);  while(!quit){  try  {  Socket socket = server.accept();  //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));  }  catch  (Exception e)  {  //  e.printStackTrace();  }  }  }  private  final  class  SocketTask  implements  Runnable{  private  Socket socket =  null;  public  SocketTask(Socket socket)  {  this.socket = socket;  }  public  void run()  {  try  {  System.out.println("accepted connection "+ 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){  //下面从协议数据中提取各项参数值  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();//生产资源id,如果需要唯一性,可以采用UUID  FileLog log =  null;  if(sourceid!=null  &&  !"".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{// 如果存在上传记录,读取已经上传的数据长度 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"));//读取已经上传的数据长度  }  }  }  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由服务器端生成,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);//指定从文件的特定位置开始写入数据  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);//实时记录已经接收的文件长度 
                       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  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;  }  public  FileLog(Long id,  String path)  {  this.id = id;  this.path = path;  }  }  }

服务端界面类:ServerWindow.java

public  class  ServerWindow  extends  Frame  {  private  FileServer s =  new  FileServer(12345);  private  Label label;  public  ServerWindow(String title)  {  super(title); label =  new  Label(); add(label,  BorderLayout.PAGE_START); label.setText("服务器已经启动");  this.addWindowListener(new  WindowListener()  {  public  void windowOpened(WindowEvent e)  {  new  Thread(new  Runnable()  {  public  void run()  {  try  { s.start();  }  catch  (Exception e)  {  // e.printStackTrace();  }  }  }).start();  }  public  void windowIconified(WindowEvent e)  {  }  public  void windowDeiconified(WindowEvent e)  {  }  public  void windowDeactivated(WindowEvent e)  {  }  public  void windowClosing(WindowEvent e)  { s.quit();  System.exit(0);  }  public  void windowClosed(WindowEvent e)  {  }  public  void windowActivated(WindowEvent e)  {  }  });  }  /**
     * @param args
     */  public  static  void main(String[] args)  throws  IOException  {  InetAddress address =  InetAddress.getLocalHost();  ServerWindow window =  new  ServerWindow("文件上传服务端:"  + address.getHostAddress()); window.setSize(400,  300); window.setVisible(true);  }  }

2)客户端(Android端)

首先是布局文件:activity_main.xml

<?xml version="1.0" encoding="utf-8"?>  <LinearLayout  xmlns:android="http://schemas.android.com/apk/res/android"  android:layout_width="fill_parent"  android:layout_height="fill_parent"  android:orientation="vertical"  android:padding="5dp">  <TextView  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:text="文件名"  android:textSize="18sp"  />  <EditText  android:id="@+id/edit_fname"  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:text="Nikki Jamal - Priceless.mp3"  />  <Button  android:id="@+id/btn_upload"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:text="上传"  />  <Button  android:id="@+id/btn_stop"  android:layout_width="wrap_content"  android:layout_height="wrap_content"  android:text="停止"  />  <ProgressBar  android:id="@+id/pgbar"  style="@android:style/Widget.ProgressBar.Horizontal"  android:layout_width="fill_parent"  android:layout_height="40px"  />  <TextView  android:id="@+id/txt_result"  android:layout_width="fill_parent"  android:layout_height="wrap_content"  android:gravity="center"  />  </LinearLayout>

因为断点续传,我们需要保存上传的进度,我们需要用到数据库,这里我们定义一个数据库 管理类:DBOpenHelper.java:

/**
 * Created by Jay on 2015/9/17 0017.
 */  public  class  DBOpenHelper  extends  SQLiteOpenHelper  {  public  DBOpenHelper(Context context)  {  super(context,  "jay.db",  null,  1);  }  @Override  public  void onCreate(SQLiteDatabase db)  { db.execSQL("CREATE TABLE IF NOT EXISTS uploadlog (_id integer primary key autoincrement, path varchar(20), sourceid varchar(20))");  }  @Override  public  void onUpgrade(SQLiteDatabase db,  int oldVersion,  int newVersion)  {  }  }

然后是数据库操作类:UploadHelper.java

/**
 * Created by Jay on 2015/9/17 0017.
 */  public  class  UploadHelper  {  private  DBOpenHelper dbOpenHelper;  public  UploadHelper(Context context)  { dbOpenHelper =  new  DBOpenHelper(context);  }  public  String getBindId(File file)  {  SQLiteDatabase db = dbOpenHelper.getReadableDatabase();  Cursor cursor = db.rawQuery("select sourceid from uploadlog where path=?",  new  String[]{file.getAbsolutePath()});  if  (cursor.moveToFirst())  {  return cursor.getString(0);  }  return  null;  }  public  void save(String sourceid,  File file)  {  SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); db.execSQL("insert into uploadlog(path,sourceid) values(?,?)",  new  Object[]{file.getAbsolutePath(), sourceid});  }  public  void  delete(File file)  {  SQLiteDatabase db = dbOpenHelper.getWritableDatabase(); db.execSQL("delete from uploadlog where path=?",  new  Object[]{file.getAbsolutePath()});  }  }

对了,别忘了客户端也要贴上那个流解析类哦,最后就是我们的MainActivity.java了:

public  class  MainActivity  extends  AppCompatActivity  implements  View.OnClickListener  {  private  EditText edit_fname;  private  Button btn_upload;  private  Button btn_stop;  private  ProgressBar pgbar;  private  TextView txt_result;  private  UploadHelper upHelper;  private  boolean flag =  true;  private  Handler handler =  new  Handler()  {  @Override  public  void handleMessage(Message msg)  { pgbar.setProgress(msg.getData().getInt("length"));  float num =  (float) pgbar.getProgress()  /  (float) pgbar.getMax();  int result =  (int)  (num *  100); txt_result.setText(result +  "%");  if  (pgbar.getProgress()  == pgbar.getMax())  {  Toast.makeText(MainActivity.this,  "上传成功",  Toast.LENGTH_SHORT).show();  }  }  };  @Override  public  void onCreate(Bundle savedInstanceState)  {  super.onCreate(savedInstanceState); setContentView(R.layout.activity_main); bindViews(); upHelper =  new  UploadHelper(this);  }  private  void bindViews()  { edit_fname =  (EditText) findViewById(R.id.edit_fname); btn_upload =  (Button) findViewById(R.id.btn_upload); btn_stop =  (Button) findViewById(R.id.btn_stop); pgbar =  (ProgressBar) findViewById(R.id.pgbar); txt_result =  (TextView) findViewById(R.id.txt_result); btn_upload.setOnClickListener(this); btn_stop.setOnClickListener(this);  }  @Override  public  void onClick(View v)  {  switch  (v.getId())  {  case R.id.btn_upload:  String filename = edit_fname.getText().toString(); flag =  true;  if  (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))  {  File file =  new  File(Environment.getExternalStorageDirectory(), filename);  if  (file.exists())  { pgbar.setMax((int) file.length()); uploadFile(file);  }  else  {  Toast.makeText(MainActivity.this,  "文件并不存在~",  Toast.LENGTH_SHORT).show();  }  }  else  {  Toast.makeText(MainActivity.this,  "SD卡不存在或者不可用",  Toast.LENGTH_SHORT).show();  }  break;  case R.id.btn_stop: flag =  false;  break;  }  }  private  void uploadFile(final  File file)  {  new  Thread(new  Runnable()  {  public  void run()  {  try  {  String sourceid = upHelper.getBindId(file);  Socket socket =  new  Socket("172.16.2.54",  12345);  OutputStream outStream = socket.getOutputStream();  String head =  "Content-Length="  + file.length()  +  ";filename="  + file.getName()  +  ";sourceid="  +  (sourceid !=  null  ? sourceid :  "")  +  "\r\n"; outStream.write(head.getBytes());  PushbackInputStream inStream =  new  PushbackInputStream(socket.getInputStream());  String response =  StreamTool.readLine(inStream);  String[] items = response.split(";");  String responseSourceid = items[0].substring(items[0].indexOf("=")  +  1);  String position = items[1].substring(items[1].indexOf("=")  +  1);  if  (sourceid ==  null)  {//如果是第一次上传文件,在数据库中不存在该文件所绑定的资源id upHelper.save(responseSourceid, file);  }  RandomAccessFile fileOutStream =  new  RandomAccessFile(file,  "r"); fileOutStream.seek(Integer.valueOf(position));  byte[] buffer =  new  byte[1024];  int len =  -1;  int length =  Integer.valueOf(position);  while  (flag &&  (len = fileOutStream.read(buffer))  !=  -1)  { outStream.write(buffer,  0, len); length += len;//累加已经上传的数据长度  Message msg =  new  Message(); msg.getData().putInt("length", length); handler.sendMessage(msg);  }  if  (length == file.length()) upHelper.delete(file); fileOutStream.close(); outStream.close(); inStream.close(); socket.close();  }  catch  (Exception e)  {  Toast.makeText(MainActivity.this,  "上传异常~",  Toast.LENGTH_SHORT).show();  }  }  }).start();  }  }

最后,还有,记得往AndroidManifest.xml中写入这些权限哦!

<!-- 在SDCard中创建与删除文件权限 -->  <uses-permission  android:name="android.permission.MOUNT_UNMOUNT_FILESYSTEMS"/>  <!-- 往SDCard写入数据权限 -->  <uses-permission  android:name="android.permission.WRITE_EXTERNAL_STORAGE"/>  <!-- 访问internet权限 -->  <uses-permission  android:name="android.permission.INTERNET"/>

4.代码下载:

Socket上传大文件demo

5.本节小结:

本节给大家介绍了基于TCP协议的Socket的另一个实例:使用Socket完成大文件的续传, 相信大家对Socket的了解更进一步,嗯,下一节再写一个例子吧,两个处于同一Wifi 下的手机相互传递数据的实例吧!就说这么多,谢谢~

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