- 浏览: 128673 次
- 性别:
- 来自: 成都
最新评论
-
yi_chao_jiang:
你好,多谢分享,问个问题,在上传数据的时候判断文件是否有上传记 ...
断点续传和下载原理分析 -
a41606709:
为什么我的tabhost显示不出来? 怎么设置在全部页面中让他 ...
TabActivity中的Tab标签详细设置 -
Zero颴:
大神篇,思路,配图都很清晰,perfect!
Android事件模型之interceptTouchEvnet ,onTouchEvent关系正解 -
QAZ503602501:
牛死人了!!!
B-树 -
mengsina:
很牛的文档。数学功底好啊
Android Matrix理论与应用详解
最近做一个文件上传和下载的应用对文件上传和下载进行了一个完整的流程分析
以来是方便自己对文件上传和下载的理解,而来便于团队内部的分享
故而做了几张图,将整体的流程都画下来,便于大家的理解和分析,如果有不完善的地方希望
大家多提意见,
由于参考了网上许多的资料,特此感谢
首先是文件上传,这个要用到服务器
关键代码:
FileServer.java
import java.io.File; import java.io.FileInputStream; import java.io.FileOutputStream; import java.io.IOException; import java.io.InputStream; 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.Set; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import util.FileLogInfo; import util.StreamTool; 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, FileLogInfo> datas = new HashMap<Long, FileLogInfo>();//存放断点数据,以后改为数据库存放 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) { e.printStackTrace(); } } /** * 启动服务 * @throws Exception */ public void start() throws Exception { server = new ServerSocket(port);//实现端口监听 while(!quit) { try { Socket socket = server.accept(); executorService.execute(new SocketTask(socket));//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 }catch (Exception e) { e.printStackTrace(); } } } private final class SocketTask implements Runnable { private Socket socket = null; public SocketTask(Socket socket) { this.socket = socket; } @Override public void run() { try { System.out.println("FileServer accepted connection "+ socket.getInetAddress()+ ":"+ socket.getPort()); //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。 InputStream inStream = socket.getInputStream(); String head = StreamTool.readLine(inStream); System.out.println("FileServer head:"+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); //生成资源id,如果需要唯一性,可以采用UUID long id = System.currentTimeMillis(); FileLogInfo log = null; if(sourceid!=null && !"".equals(sourceid)) { id = Long.valueOf(sourceid); //查找上传的文件是否存在上传记录 log = find(id); } File file = null; int position = 0; //如果上传的文件不存在上传记录,为文件添加跟踪记录 if(log==null) { //设置存放的位置与当前应用的位置有关 File dir = new File("c:/temp/"); if(!dir.exists()) dir.mkdirs(); file = new File(dir, filename); //如果上传的文件发生重名,然后进行改名 if(file.exists()) { filename = filename.substring(0, filename.indexOf(".")-1)+ dir.listFiles().length+ filename.substring(filename.indexOf(".")); file = new File(dir, filename); } save(id, file); } // 如果上传的文件存在上传记录,读取上次的断点位置 else { System.out.println("FileServer have exits log not null"); //从上传记录中得到文件的路径 file = new File(log.getPath()); if(file.exists()) { File logFile = new File(file.getParentFile(), file.getName()+".log"); if(logFile.exists()) { Properties properties = new Properties(); properties.load(new FileInputStream(logFile)); //读取断点位置 position = Integer.valueOf(properties.getProperty("length")); } } } //***************************上面是对协议头的处理,下面正式接收数据*************************************** //向客户端请求传输数据 OutputStream outStream = socket.getOutputStream(); String response = "sourceid="+ id+ ";position="+ position+ "%"; //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=position //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"); //设置文件长度 if(position==0) fileOutStream.setLength(Integer.valueOf(filelength)); //移动文件指定的位置开始写入数据 fileOutStream.seek(position); byte[] buffer = new byte[1024]; int len = -1; int length = position; //从输入流中读取数据写入到文件中,并将已经传入的文件长度写入配置文件,实时记录文件的最后保存位置 while( (len=inStream.read(buffer)) != -1) { 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")); //实时记录文件的最后保存位置 properties.store(logFile, null); logFile.close(); } //如果长传长度等于实际长度则表示长传成功 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) { e.printStackTrace(); } } } } /** * 查找在记录中是否有sourceid的文件 * @param sourceid * @return */ public FileLogInfo find(Long sourceid) { return datas.get(sourceid); } /** * 保存上传记录,日后可以改成通过数据库存放 * @param id * @param saveFile */ public void save(Long id, File saveFile) { System.out.println("save logfile "+id); datas.put(id, new FileLogInfo(id, saveFile.getAbsolutePath())); } /** * 当文件上传完毕,删除记录 * @param sourceid */ public void delete(long sourceid) { System.out.println("delete logfile "+sourceid); if(datas.containsKey(sourceid)) datas.remove(sourceid); } }
由于在上面的流程图中已经进行了详细的分析,我在这儿就不讲了,只是在存储数据的时候服务器没有用数据库去存储,这儿只是为了方便,所以要想测试断点上传,服务器是不能停的,否则数据就没有了,在以后改进的时候应该用数据库去存储数据。
文件上传客户端:
关键代码:
UploadActivity.java
package com.hao; import java.io.File; import java.util.List; import com.hao.upload.UploadThread; import com.hao.upload.UploadThread.UploadProgressListener; import com.hao.util.ConstantValues; import com.hao.util.FileBrowserActivity; import android.app.Activity; import android.app.Dialog; import android.app.ProgressDialog; import android.content.DialogInterface; import android.content.Intent; import android.content.res.Resources; import android.net.Uri; import android.os.Bundle; import android.os.Environment; import android.os.Handler; import android.os.Message; import android.util.Log; import android.view.View; import android.view.View.OnClickListener; import android.widget.Button; import android.widget.TextView; import android.widget.Toast; /** * * @author Administrator * */ public class UploadActivity extends Activity implements OnClickListener{ private static final String TAG = "SiteFileFetchActivity"; private Button download, upload, select_file; private TextView info; private static final int PROGRESS_DIALOG = 0; private ProgressDialog progressDialog; private UploadThread uploadThread; private String uploadFilePath = null; private String fileName; /** Called when the activity is first created. */ @Override public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.upload); initView(); } private void initView(){ download = (Button) findViewById(R.id.download); download.setOnClickListener(this); upload = (Button) findViewById(R.id.upload); upload.setOnClickListener(this); info = (TextView) findViewById(R.id.info); select_file = (Button) findViewById(R.id.select_file); select_file.setOnClickListener(this); } @Override protected void onActivityResult(int requestCode, int resultCode, Intent data) { // TODO Auto-generated method stub super.onActivityResult(requestCode, resultCode, data); if (resultCode == RESULT_OK) { if (requestCode == 1) { Uri uri = data.getData(); // 接收用户所选文件的路径 info.setText("select: " + uri); // 在界面上显示路径 uploadFilePath = uri.getPath(); int last = uploadFilePath.lastIndexOf("/"); uploadFilePath = uri.getPath().substring(0, last+1); fileName = uri.getLastPathSegment(); } } } protected Dialog onCreateDialog(int id) { switch(id) { case PROGRESS_DIALOG: progressDialog = new ProgressDialog(UploadActivity.this); progressDialog.setProgressStyle(ProgressDialog.STYLE_HORIZONTAL); progressDialog.setButton("暂停", new DialogInterface.OnClickListener() { @Override public void onClick(DialogInterface dialog, int which) { // TODO Auto-generated method stub uploadThread.closeLink(); dialog.dismiss(); } }); progressDialog.setMessage("正在上传..."); progressDialog.setMax(100); return progressDialog; default: return null; } } /** * 使用Handler给创建他的线程发送消息, * 匿名内部类 */ private Handler handler = new Handler() { @Override public void handleMessage(Message msg) { //获得上传长度的进度 int length = msg.getData().getInt("size"); progressDialog.setProgress(length); if(progressDialog.getProgress()==progressDialog.getMax())//上传成功 { progressDialog.dismiss(); Toast.makeText(UploadActivity.this, getResources().getString(R.string.upload_over), 1).show(); } } }; @Override public void onClick(View v) { // TODO Auto-generated method stub Resources r = getResources(); switch(v.getId()){ case R.id.select_file: Intent intent = new Intent(); //设置起始目录和查找的类型 intent.setDataAndType(Uri.fromFile(new File("/sdcard")), "*/*");//"*/*"表示所有类型,设置起始文件夹和文件类型 intent.setClass(UploadActivity.this, FileBrowserActivity.class); startActivityForResult(intent, 1); break; case R.id.download: startActivity(new Intent(UploadActivity.this, SmartDownloadActivity.class)); break; case R.id.upload: if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED))//判断SDCard是否存在 { if(uploadFilePath == null){ Toast.makeText(UploadActivity.this, "还没设置上传文件", 1).show(); } System.out.println("uploadFilePath:"+uploadFilePath+" "+fileName); //取得SDCard的目录 File uploadFile = new File(new File(uploadFilePath), fileName); Log.i(TAG, "filePath:"+uploadFile.toString()); if(uploadFile.exists()) { showDialog(PROGRESS_DIALOG); info.setText(uploadFile+" "+ConstantValues.HOST+":"+ConstantValues.PORT); progressDialog.setMax((int) uploadFile.length());//设置长传文件的最大刻度 uploadThread = new UploadThread(UploadActivity.this, uploadFile, ConstantValues.HOST, ConstantValues.PORT); uploadThread.setListener(new UploadProgressListener() { @Override public void onUploadSize(int size) { // TODO Auto-generated method stub Message msg = new Message(); msg.getData().putInt("size", size); handler.sendMessage(msg); } }); uploadThread.start(); } else { Toast.makeText(UploadActivity.this, "文件不存在", 1).show(); } } else { Toast.makeText(UploadActivity.this, "SDCard不存在!", 1).show(); } break; } } }
UploadThread.java
package com.hao.upload; import java.io.File; import java.io.IOException; import java.io.InputStream; import java.io.OutputStream; import java.io.RandomAccessFile; import java.net.Socket; import android.content.Context; import android.util.Log; import com.hao.db.UploadLogService; import com.hao.util.StreamTool; public class UploadThread extends Thread { private static final String TAG = "UploadThread"; /*需要上传文件的路径*/ private File uploadFile; /*上传文件服务器的IP地址*/ private String dstName; /*上传服务器端口号*/ private int dstPort; /*上传socket链接*/ private Socket socket; /*存储上传的数据库*/ private UploadLogService logService; private UploadProgressListener listener; public UploadThread(Context context, File uploadFile, final String dstName,final int dstPort){ this.uploadFile = uploadFile; this.dstName = dstName; this.dstPort = dstPort; logService = new UploadLogService(context); } public void setListener(UploadProgressListener listener) { this.listener = listener; } /** * 模拟断开连接 */ public void closeLink(){ try{ if(socket != null) socket.close(); }catch(IOException e){ e.printStackTrace(); Log.e(TAG, "close socket fail"); } } @Override public void run() { // TODO Auto-generated method stub try { // 判断文件是否已有上传记录 String souceid = logService.getBindId(uploadFile); // 构造拼接协议 String head = "Content-Length=" + uploadFile.length() + ";filename=" + uploadFile.getName() + ";sourceid=" + (souceid == null ? "" : souceid) + "%"; // 通过Socket取得输出流 socket = new Socket(dstName, dstPort); OutputStream outStream = socket.getOutputStream(); outStream.write(head.getBytes()); Log.i(TAG, "write to outStream"); InputStream inStream = socket.getInputStream(); // 获取到字符流的id与位置 String response = StreamTool.readLine(inStream); Log.i(TAG, "response:" + response); String[] items = response.split(";"); String responseid = items[0].substring(items[0].indexOf("=") + 1); String position = items[1].substring(items[1].indexOf("=") + 1); // 代表原来没有上传过此文件,往数据库添加一条绑定记录 if (souceid == null) { logService.save(responseid, uploadFile); } RandomAccessFile fileOutStream = new RandomAccessFile(uploadFile, "r"); // 查找上次传送的最终位置,并从这开始传送 fileOutStream.seek(Integer.valueOf(position)); byte[] buffer = new byte[1024]; int len = -1; // 初始化上传的数据长度 int length = Integer.valueOf(position); while ((len = fileOutStream.read(buffer)) != -1) { outStream.write(buffer, 0, len); // 设置长传数据长度 length += len; listener.onUploadSize(length); } fileOutStream.close(); outStream.close(); inStream.close(); socket.close(); // 判断上传完则删除数据 if (length == uploadFile.length()) logService.delete(uploadFile); } catch (Exception e) { e.printStackTrace(); } } public interface UploadProgressListener{ void onUploadSize(int size); } }
下面是多线程下载
SmartDownloadActivity.java
package com.hao; import java.io.File; import com.hao.R; import com.hao.R.id; import com.hao.R.layout; import com.hao.download.SmartFileDownloader; import com.hao.download.SmartFileDownloader.SmartDownloadProgressListener; import com.hao.util.ConstantValues; 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.ProgressBar; import android.widget.TextView; import android.widget.Toast; /** * * @author Administrator * */ public class SmartDownloadActivity extends Activity { private ProgressBar downloadbar; private TextView resultView; private String path = ConstantValues.DOWNLOAD_URL; SmartFileDownloader loader; private Handler handler = new Handler() { @Override // 信息 public void handleMessage(Message msg) { switch (msg.what) { case 1: int size = msg.getData().getInt("size"); downloadbar.setProgress(size); float result = (float) downloadbar.getProgress() / (float) downloadbar.getMax(); int p = (int) (result * 100); resultView.setText(p + "%"); if (downloadbar.getProgress() == downloadbar.getMax()) Toast.makeText(SmartDownloadActivity.this, "下载成功", 1).show(); break; case -1: Toast.makeText(SmartDownloadActivity.this, msg.getData().getString("error"), 1).show(); break; } } }; public void onCreate(Bundle savedInstanceState) { super.onCreate(savedInstanceState); setContentView(R.layout.download); Button button = (Button) this.findViewById(R.id.button); Button closeConn = (Button) findViewById(R.id.closeConn); closeConn.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { // TODO Auto-generated method stub if(loader != null){ finish(); }else{ Toast.makeText(SmartDownloadActivity.this, "还没有开始下载,不能暂停", 1).show(); } } }); downloadbar = (ProgressBar) this.findViewById(R.id.downloadbar); resultView = (TextView) this.findViewById(R.id.result); resultView.setText(path); button.setOnClickListener(new View.OnClickListener() { @Override public void onClick(View v) { if (Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)) { download(path, ConstantValues.FILE_PATH); } else { Toast.makeText(SmartDownloadActivity.this, "没有SDCard", 1).show(); } } }); } // 对于UI控件的更新只能由主线程(UI线程)负责,如果在非UI线程更新UI控件,更新的结果不会反映在屏幕上,某些控件还会出错 private void download(final String path, final File dir) { new Thread(new Runnable() { @Override public void run() { try { loader = new SmartFileDownloader(SmartDownloadActivity.this, path, dir, 3); int length = loader.getFileSize();// 获取文件的长度 downloadbar.setMax(length); loader.download(new SmartDownloadProgressListener() { @Override public void onDownloadSize(int size) {// 可以实时得到文件下载的长度 Message msg = new Message(); msg.what = 1; msg.getData().putInt("size", size); handler.sendMessage(msg); } }); } catch (Exception e) { Message msg = new Message();// 信息提示 msg.what = -1; msg.getData().putString("error", "下载失败");// 如果下载错误,显示提示失败! handler.sendMessage(msg); } } }).start();// 开始 } }
这个单个的下载线程
SmartDownloadThread.java
package com.hao.download; import java.io.File; import java.io.InputStream; import java.io.RandomAccessFile; import java.net.HttpURLConnection; import java.net.URL; import android.util.Log; /** * 线程下载 * @author Administrator * */ public class SmartDownloadThread extends Thread { private static final String TAG = "SmartDownloadThread"; private File saveFile; private URL downUrl; private int block; /* *下载开始位置 */ private int threadId = -1; private int downLength; private boolean finish = false; private SmartFileDownloader downloader; public SmartDownloadThread(SmartFileDownloader downloader, URL downUrl, File saveFile, int block, int downLength, int threadId) { this.downUrl = downUrl; this.saveFile = saveFile; this.block = block; this.downloader = downloader; this.threadId = threadId; this.downLength = downLength; } @Override public void run() { if (downLength < block) {// 未下载完成 try { HttpURLConnection http = (HttpURLConnection) downUrl .openConnection(); http.setConnectTimeout(5 * 1000); http.setRequestMethod("GET"); http.setRequestProperty("Accept","image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*"); http.setRequestProperty("Accept-Language", "zh-CN"); http.setRequestProperty("Referer", downUrl.toString()); http.setRequestProperty("Charset", "UTF-8"); int startPos = block * (threadId - 1) + downLength;// 开始位置 int endPos = block * threadId - 1;// 结束位置 http.setRequestProperty("Range", "bytes=" + startPos + "-" + endPos);// 设置获取实体数据的范围 http.setRequestProperty("User-Agent","Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"); http.setRequestProperty("Connection", "Keep-Alive"); InputStream inStream = http.getInputStream(); byte[] buffer = new byte[1024]; int offset = 0; print("Thread " + this.threadId + " start download from position " + startPos); RandomAccessFile threadfile = new RandomAccessFile(this.saveFile, "rwd"); threadfile.seek(startPos); while ((offset = inStream.read(buffer, 0, 1024)) != -1) { threadfile.write(buffer, 0, offset); downLength += offset; downloader.update(this.threadId, downLength); downloader.saveLogFile(); downloader.append(offset); } threadfile.close(); inStream.close(); print("Thread " + this.threadId + " download finish"); this.finish = true; } catch (Exception e) { this.downLength = -1; print("Thread " + this.threadId + ":" + e); } } } private static void print(String msg) { Log.i(TAG, msg); } /** * 下载是否完成 * @return */ public boolean isFinish() { return finish; } /** * 已经下载的内容大小 * @return 如果返回值为-1,代表下载失败 */ public long getDownLength() { return downLength; } }
总得下载线程
SmartFileDownloader.java
package com.hao.download; import java.io.File; import java.io.RandomAccessFile; import java.net.HttpURLConnection; import java.net.URL; import java.util.LinkedHashMap; import java.util.Map; import java.util.UUID; import java.util.concurrent.ConcurrentHashMap; import java.util.regex.Matcher; import java.util.regex.Pattern; import com.hao.db.DownloadFileService; import android.content.Context; import android.util.Log; /** * 文件下载主程序 * @author Administrator * */ public class SmartFileDownloader { private static final String TAG = "SmartFileDownloader"; private Context context; private DownloadFileService fileService; /* 已下载文件长度 */ private int downloadSize = 0; /* 原始文件长度 */ private int fileSize = 0; /*原始文件名*/ private String fileName; /* 线程数 */ private SmartDownloadThread[] threads; /* 本地保存文件 */ private File saveFile; /* 缓存各线程下载的长度 */ private Map<Integer, Integer> data = new ConcurrentHashMap<Integer, Integer>(); /* 每条线程下载的长度 */ private int block; /* 下载路径 */ private String downloadUrl; /** * 获取文件名 */ public String getFileName(){ return this.fileName; } /** * 获取线程数 */ public int getThreadSize() { return threads.length; } /** * 获取文件大小 * @return */ public int getFileSize() { return fileSize; } /** * 累计已下载大小 * @param size */ protected synchronized void append(int size) { downloadSize += size; } /** * 更新指定线程最后下载的位置 * @param threadId 线程id * @param pos 最后下载的位置 */ protected void update(int threadId, int pos) { this.data.put(threadId, pos); } /** * 保存记录文件 */ protected synchronized void saveLogFile() { this.fileService.update(this.downloadUrl, this.data); } /** * 构建文件下载器 * @param downloadUrl 下载路径 * @param fileSaveDir 文件保存目录 * @param threadNum 下载线程数 */ public SmartFileDownloader(Context context, String downloadUrl, File fileSaveDir, int threadNum) { try { this.context = context; this.downloadUrl = downloadUrl; fileService = new DownloadFileService(this.context); URL url = new URL(this.downloadUrl); if (!fileSaveDir.exists()) fileSaveDir.mkdirs(); this.threads = new SmartDownloadThread[threadNum]; HttpURLConnection conn = (HttpURLConnection) url.openConnection(); conn.setConnectTimeout(5 * 1000); conn.setRequestMethod("GET"); conn.setRequestProperty("Accept", "image/gif, image/jpeg, image/pjpeg, image/pjpeg, application/x-shockwave-flash, application/xaml+xml, application/vnd.ms-xpsdocument, application/x-ms-xbap, application/x-ms-application, application/vnd.ms-excel, application/vnd.ms-powerpoint, application/msword, */*"); conn.setRequestProperty("Accept-Language", "zh-CN"); conn.setRequestProperty("Referer", downloadUrl); conn.setRequestProperty("Charset", "UTF-8"); conn.setRequestProperty("User-Agent", "Mozilla/4.0 (compatible; MSIE 8.0; Windows NT 5.2; Trident/4.0; .NET CLR 1.1.4322; .NET CLR 2.0.50727; .NET CLR 3.0.04506.30; .NET CLR 3.0.4506.2152; .NET CLR 3.5.30729)"); conn.setRequestProperty("Connection", "Keep-Alive"); conn.connect(); printResponseHeader(conn); if (conn.getResponseCode() == 200) { this.fileSize = conn.getContentLength();// 根据响应获取文件大小 if (this.fileSize <= 0) throw new RuntimeException("Unkown file size "); fileName = getFileName(conn); this.saveFile = new File(fileSaveDir, fileName);/* 保存文件 */ Map<Integer, Integer> logdata = fileService.getData(downloadUrl); if (logdata.size() > 0) { for (Map.Entry<Integer, Integer> entry : logdata.entrySet()) data.put(entry.getKey(), entry.getValue()); } //划分每个线程下载文件长度 this.block = (this.fileSize % this.threads.length) == 0 ? this.fileSize / this.threads.length : this.fileSize / this.threads.length + 1; if (this.data.size() == this.threads.length) { for (int i = 0; i < this.threads.length; i++) { this.downloadSize += this.data.get(i + 1); } print("已经下载的长度" + this.downloadSize); } } else { throw new RuntimeException("server no response "); } } catch (Exception e) { print(e.toString()); throw new RuntimeException("don't connection this url"); } } /** * 获取文件名 */ private String getFileName(HttpURLConnection conn) { String filename = this.downloadUrl.substring(this.downloadUrl.lastIndexOf('/') + 1);//链接的最后一个/就是文件名 if (filename == null || "".equals(filename.trim())) {// 如果获取不到文件名称 for (int i = 0;; i++) { String mine = conn.getHeaderField(i); print("ConnHeader:"+mine+" "); if (mine == null) break; if ("content-disposition".equals(conn.getHeaderFieldKey(i).toLowerCase())) { Matcher m = Pattern.compile(".*filename=(.*)").matcher(mine.toLowerCase()); if (m.find()) return m.group(1); } } filename = UUID.randomUUID() + ".tmp";// 默认取一个文件名 } return filename; } /** * 开始下载文件 * * @param listener * 监听下载数量的变化,如果不需要了解实时下载的数量,可以设置为null * @return 已下载文件大小 * @throws Exception */ public int download(SmartDownloadProgressListener listener) throws Exception { try { RandomAccessFile randOut = new RandomAccessFile(this.saveFile, "rw"); if (this.fileSize > 0) randOut.setLength(this.fileSize); randOut.close(); URL url = new URL(this.downloadUrl); if (this.data.size() != this.threads.length) { this.data.clear();// 清除数据 for (int i = 0; i < this.threads.length; i++) { this.data.put(i + 1, 0); } } for (int i = 0; i < this.threads.length; i++) { int downLength = this.data.get(i + 1); if (downLength < this.block && this.downloadSize < this.fileSize) { // 该线程未完成下载时,继续下载 this.threads[i] = new SmartDownloadThread(this, url, this.saveFile, this.block, this.data.get(i + 1), i + 1); this.threads[i].setPriority(7); this.threads[i].start(); } else { this.threads[i] = null; } } this.fileService.save(this.downloadUrl, this.data); boolean notFinish = true;// 下载未完成 while (notFinish) {// 循环判断是否下载完毕 Thread.sleep(900); notFinish = false;// 假定下载完成 for (int i = 0; i < this.threads.length; i++) { if (this.threads[i] != null && !this.threads[i].isFinish()) { notFinish = true;// 下载没有完成 if (this.threads[i].getDownLength() == -1) {// 如果下载失败,再重新下载 this.threads[i] = new SmartDownloadThread(this, url, this.saveFile, this.block, this.data.get(i + 1), i + 1); this.threads[i].setPriority(7); this.threads[i].start(); } } } if (listener != null) listener.onDownloadSize(this.downloadSize); } fileService.delete(this.downloadUrl); } catch (Exception e) { print(e.toString()); throw new Exception("file download fail"); } return this.downloadSize; } /** * 获取Http响应头字段 * * @param http * @return */ public static Map<String, String> getHttpResponseHeader( HttpURLConnection http) { Map<String, String> header = new LinkedHashMap<String, String>(); for (int i = 0;; i++) { String mine = http.getHeaderField(i); if (mine == null) break; header.put(http.getHeaderFieldKey(i), mine); } return header; } /** * 打印Http头字段 * * @param http */ public static void printResponseHeader(HttpURLConnection http) { Map<String, String> header = getHttpResponseHeader(http); for (Map.Entry<String, String> entry : header.entrySet()) { String key = entry.getKey() != null ? entry.getKey() + ":" : ""; print(key + entry.getValue()); } } // 打印日志 private static void print(String msg) { Log.i(TAG, msg); } public interface SmartDownloadProgressListener { public void onDownloadSize(int size); } }
好了这里只是将主要的代码分享出来,主要是为了了解他的基本流程,然后自己可以扩展,和优化
评论
6 楼
yi_chao_jiang
2016-08-18
你好,多谢分享,问个问题,在上传数据的时候判断文件是否有上传记录,这个是如何判断的?
5 楼
hao3100590
2012-06-08
hh777 写道
暂停怎么实现?
暂停后,位置会记录下来,下次会从那里继续下载
具体的过程,看上面的图,很清楚
4 楼
hao3100590
2012-06-08
hh777 写道
暂停怎么实现?
在SmartDownloadActivity.java的60行有暂停按钮,模拟暂停(将链接断了)
3 楼
hh777
2012-06-08
暂停怎么实现?
2 楼
zdb_cn
2011-12-13
强大...学习了
1 楼
ylzyd12345
2011-12-07
标记一下,thx for share
发表评论
-
手机游戏的优化
2012-05-14 15:46 1032手机游戏设计中由于设备性能限制,可能出现资源不足的情况 ... -
带进度和时间的播放器
2011-12-19 21:15 2852最近由于需要,做了一个音乐播放控制view,在上面需要能 * ... -
Android Matrix理论与应用详解
2011-11-21 10:58 17559本文转自http://blog.csdn.net/kuku20 ... -
Android图片处理(Matrix,ColorMatrix)
2011-11-20 22:47 3217在编程中有时候需要对图片做特殊的处理,比如将图片做出黑 ... -
Android事件模型之interceptTouchEvnet ,onTouchEvent关系正解
2011-11-19 20:53 7179参考文档: http://blog.cs ... -
Android下基于XML的 Graphics(转载)
2011-04-23 15:39 1264Android下基于XML的 Graphi ... -
Android之父深入解析Android
2011-04-22 16:10 1007Android之父深入解析Android By: 海 ... -
实现ListView的条目下自动隐藏显示Button的方法
2011-04-17 09:42 6567这个想法是我在看了sina ... -
TabActivity中的Tab标签详细设置
2011-03-24 17:19 7207参考链接: http://www.iteye.com/ ...
相关推荐
本文先从断点续传问题开始,介绍断点续传概述和原理。接着结合笔者调研中尝试的AFHTTPRequestOpeartion,简单分析源码。最后分别基于NSURLConnection,NSURLSessionDataTask和NSURLSessionDownloadTask去实现应用...
主要介绍了HTML5实现文件断点续传的方法,断点续传的原理分析,本文给大家介绍的非常详细,需要的朋友参考下
本文先从断点续传问题开始,介绍断点续传概述和原理。接着结合笔者调研中尝试的 AFHTTPRequestOpeartion,简单分析源码。最后分别基于 NSURLConnection,NSURLSessionDataTask 和 NSURLSessionDownloadTask 去实现...
前言 之前项目需要上传大文件的功能,上传大文件经常遇到上传一半由于网络或者其他一些原因上传失败。然后又得重新上传(很麻烦),所以就想能不能...原理分析 Android客户端 首先,android端调用服务器接口1,参数为f
毕业论文——包含了一篇探讨多线程与线程安全实践项目背景、技术原理和实现过程的学术论文,可作为论文撰写参考。通过阅读论文,学习者可以了解项目的理论基础,深入理解项目的实现细节,提升分析和解决问题的能力。...
非常好的下载器设计需求分析文档,包含对http、ftp协议分块下载和断点续传原理的介绍。
断点续传(需服务器支持) 项目地址:https://github.com/4ndroidev/DownloadManager.git 效果图 实现原理 下载任务流程图 由上图可知,任务执行流程大致如下 创建任务,并做准备,设置监听器等操作 根据任务...
3.3 断点续传原理 8 4 需求分析 10 4.1用户需求分析 10 4.2 业务流分析 11 5. 整体设计 11 5.1 系统设计要点 11 5.2 系统总体功能结构 12 5.3 开发环境:myeclipse SWT 15 5.4 URL类和URLConnection类的使用...
在网友的要求下又新增了自定义代理功能和断点续传功能 上一周经过各位网友的测试,有的能运行,有的不能运行,主要是由于java环境的配置问题。 既然大家呼吁exe版,这个周末我花了三天时间用纯C语言写了这个exe...
redis原理分析并实现断点续爬以及分布式爬虫9.scrapy_splash组件的使用10.scrapy的日志信息与配置11.scrapyd部署scrapy项目12.gerapy爬虫管理13.gerapy爬虫管理13.scrapy总结图14.crawlspider类的使用
8.scrapy_redis原理分析并实现断点续爬以及分布式爬虫 9.scrapy_splash组件的使用 10.scrapy的日志信息与配置 11.scrapyd部署scrapy项目 12.gerapy爬虫管理 13.gerapy爬虫管理 13.scrapy总结图 14.crawlspider类的...
13.2.3 FTP协议多线程下载和断点续传的实现 295 13.2.4 实例 306 13.3 使用HTTP进行多线程下载和断点续传 307 13.3.1 HTTP协议简介 307 13.3.2 HTTP协议的内部操作过程 308 13.3.3 HTTP协议多线程下载和断点续...
此外,还支持断点续传功能,方便用户在传输过程中进行暂停和恢复操作。 3. **安全性**:项目采用了多种安全措施,包括用户身份验证、数据加密和防火墙保护等,确保用户信息和文件传输的安全。同时,系统还提供了隐私...
2> 网络--通过HTTP协议实现多线程断点续传下载 3> 为应用添加新的Activity与参数传递 4> 意图 第六天 1> Activity的生命周期 2> 广播接收者(实现短信监听) 3> 服务与语音刻录(实现电话监听)、使用AIDL实现进程...
结合模拟常用系统环境进行方案设计的试验,得出基于Redo log复制技术的数据库备份方式,不仅具有高效的资源利用、跨平台数据库同步、主备库双活、断点续传等功能,可以实现Oracle数据库的高可用、提高保护数据的安全...
2> 网络--通过HTTP协议实现多线程断点续传下载 3> 为应用添加新的Activity与参数传递 4> 意图 第六天 1> Activity的生命周期 2> 广播接收者(实现短信监听) 3> 服务与语音刻录(实现电话监听)、使用AIDL实现进程通信...
第13章主要介绍了基于HTTP协议的下载工具,该工具具有多线程下载、断点续传的功能。 本书注重理论指导性和工程实践性,书中提供的各个网络应用程序只要稍加修改就可以为读者所用。本书不仅适用于使用Visual C# 2005...
基于JAVA的UDP服务器模型源代码,内含UDP服务器端模型和UDP客户端模型两个小程序,向JAVA初学者演示UDP C/S结构的原理。 简单聊天软件CS模式 2个目标文件 一个简单的CS模式的聊天软件,用socket实现,比较简单。 ...
基于JAVA的UDP服务器模型源代码,内含UDP服务器端模型和UDP客户端模型两个小程序,向JAVA初学者演示UDP C/S结构的原理。 简单聊天软件CS模式 2个目标文件 一个简单的CS模式的聊天软件,用socket实现,比较简单。 ...