• Android常用的工具类收藏用


    一、检查网络是否可用

    import android.app.AlertDialog;
    import android.content.Context;
    import android.content.DialogInterface;
    import android.net.ConnectivityManager;
    import android.net.NetworkInfo;


    public class ConnectionUtil {
    /**
    * 检查网络是否可用
    * @param context应用程序的上下文对象
    * @return
    */
    public static boolean isNetworkAvailable(Context context) {
    ConnectivityManager connectivity = (ConnectivityManager) context
    .getSystemService(Context.CONNECTIVITY_SERVICE);//获取系统网络连接管理器
    if (connectivity == null) {//如果网络管理器为null
    return false; //返回false表明网络无法连接
    } else {
    NetworkInfo[] info = connectivity.getAllNetworkInfo();//获取所有的网络连接对象
    if (info != null) {//网络信息不为null时
    for (int i = 0; i < info.length; i++) {//遍历网路连接对象
    if (info[i].isConnected()) {//当有一个网络连接对象连接上网络时
    return true; //返回true表明网络连接正常
    }
    }
    }
    }
    return false; 
    }

    public static void httpTest(final Context ctx,String title,String msg) {
    if (!isNetworkAvailable(ctx)) {
    AlertDialog.Builder builders = new AlertDialog.Builder(ctx);
    builders.setTitle(title);
    builders.setMessage(msg);
    builders.setPositiveButton(android.R.string.ok,
    new DialogInterface.OnClickListener() {
    public void onClick(DialogInterface dialog, int which) {
    //alert.dismiss();
    }
    });
    AlertDialog alert = builders.create();
    alert.show();
    }
    }

    }

    二、读取流文件

    StreamTool.java

    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();
    }
    }

    三、文件断点上传

    MainActivity.java

    import java.io.File;
    import java.io.OutputStream;
    import java.io.PushbackInputStream;
    import java.io.RandomAccessFile;
    import java.net.Socket;
    import cn.itcast.service.UploadLogService;
    import cn.itcast.utils.StreamTool;
    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;


    public class MainActivity extends Activity {
        private EditText filenameText;
        private TextView resultView;
        private ProgressBar uploadbar;
        private UploadLogService service;
        private Handler handler = new Handler(){
    @Override
    public void handleMessage(Message msg) {
    uploadbar.setProgress(msg.getData().getInt("length"));
    float num = (float)uploadbar.getProgress() / (float)uploadbar.getMax();
    int result = (int)(num * 100);
    resultView.setText(result + "%");
    if(uploadbar.getProgress() == uploadbar.getMax()){
    Toast.makeText(MainActivity.this, R.string.success, 1).show();
    }
    }
        };
        
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            
            service =  new UploadLogService(this);
            filenameText = (EditText)findViewById(R.id.filename);
            resultView = (TextView)findViewById(R.id.result);
            uploadbar = (ProgressBar)findViewById(R.id.uploadbar);
            Button button = (Button)findViewById(R.id.button);
            button.setOnClickListener(new View.OnClickListener() {
    public void onClick(View v) {
    String filename = filenameText.getText().toString();
    if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
    File file = new File(Environment.getExternalStorageDirectory(), filename);
    if(file.exists()){
    uploadbar.setMax((int)file.length());
    uploadFile(file);
    }else{
    Toast.makeText(MainActivity.this, R.string.notexsit, 1).show();
    }
    }else{
    Toast.makeText(MainActivity.this, R.string.sdcarderror, 1).show();
    }
    }
    });
        }


    private void uploadFile(final File file) {
    new Thread(new Runnable() {
    public void run() {
    try {
    String sourceid = service.getBindId(file);
    Socket socket = new Socket("192.168.1.100", 7878);//根据IP地址和端口不同更改
               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,入库
    service.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( (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()) service.delete(file);
    fileOutStream.close();
    outStream.close();
               inStream.close();
               socket.close();
           } catch (Exception e) {                    
            Toast.makeText(MainActivity.this, R.string.error, 1).show();
           }
    }
    }).start();
    }
    }

    DBOpenHelper.java//数据库

    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, "itcast.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) {
    // TODO Auto-generated method stub
    }

    }

    UploadLogService.java


    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){
    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()});
    }
     }

    四、多线程断点下载

    MainActivity.java

    import java.io.File;
    import cn.itcast.net.download.DownloadProgressListener;
    import cn.itcast.net.download.FileDownloader;
    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;


    public class MainActivity extends Activity {
        private EditText pathText;
        private TextView resultView;
        private Button downloadButton;
        private Button stopbutton;
        private ProgressBar progressBar;
        //hanlder的作用是用于往创建Hander对象所在的线程所绑定的消息队列发送消息
        private Handler handler = new UIHander();
        
        private final class UIHander extends Handler{
    public void handleMessage(Message msg) {
    switch (msg.what) {
    case 1:
    int size = msg.getData().getInt("size");
    progressBar.setProgress(size);
    float num = (float)progressBar.getProgress() / (float)progressBar.getMax();
    int result = (int)(num * 100);
    resultView.setText(result+ "%");
    if(progressBar.getProgress() == progressBar.getMax()){
    Toast.makeText(getApplicationContext(), R.string.success, 1).show();
    }
    break;


    case -1:
    Toast.makeText(getApplicationContext(), R.string.error, 1).show();
    break;
    }
    }
        }
        
        @Override
        public void onCreate(Bundle savedInstanceState) {
            super.onCreate(savedInstanceState);
            setContentView(R.layout.main);
            
            pathText = (EditText) this.findViewById(R.id.path);
            resultView = (TextView) this.findViewById(R.id.resultView);
            downloadButton = (Button) this.findViewById(R.id.downloadbutton);
            stopbutton = (Button) this.findViewById(R.id.stopbutton);
            progressBar = (ProgressBar) this.findViewById(R.id.progressBar);
            ButtonClickListener listener = new ButtonClickListener();
            downloadButton.setOnClickListener(listener);
            stopbutton.setOnClickListener(listener);
        }
        
        private final class ButtonClickListener implements View.OnClickListener{
    public void onClick(View v) {
    switch (v.getId()) {
    case R.id.downloadbutton:
    String path = pathText.getText().toString();
    if(Environment.getExternalStorageState().equals(Environment.MEDIA_MOUNTED)){
    File saveDir = Environment.getExternalStorageDirectory();
    download(path, saveDir);
    }else{
    Toast.makeText(getApplicationContext(), R.string.sdcarderror, 1).show();
    }
    downloadButton.setEnabled(false);
    stopbutton.setEnabled(true);
    break;


    case R.id.stopbutton:
    exit();
    downloadButton.setEnabled(true);
    stopbutton.setEnabled(false);
    break;
    }
    }
    /*
    由于用户的输入事件(点击button, 触摸屏幕....)是由主线程负责处理的,如果主线程处于工作状态,
    此时用户产生的输入事件如果没能在5秒内得到处理,系统就会报“应用无响应”错误。
    所以在主线程里不能执行一件比较耗时的工作,否则会因主线程阻塞而无法处理用户的输入事件,
    导致“应用无响应”错误的出现。耗时的工作应该在子线程里执行。
    */
    private DownloadTask task;
    /**
    * 退出下载
    */
    public void exit(){
    if(task!=null) task.exit();
    }
    private void download(String path, File saveDir) {//运行在主线程
    task = new DownloadTask(path, saveDir);
    new Thread(task).start();
    }


    /*
    * UI控件画面的重绘(更新)是由主线程负责处理的,如果在子线程中更新UI控件的值,更新后的值不会重绘到屏幕上
    * 一定要在主线程里更新UI控件的值,这样才能在屏幕上显示出来,不能在子线程中更新UI控件的值
    */
    private final class DownloadTask implements Runnable{
    private String path;
    private File saveDir;
    private FileDownloader loader;
    public DownloadTask(String path, File saveDir) {
    this.path = path;
    this.saveDir = saveDir;
    }
    /**
    * 退出下载
    */
    public void exit(){
    if(loader!=null) loader.exit();
    }

    public void run() {
    try {
    loader = new FileDownloader(getApplicationContext(), path, saveDir, 3);
    progressBar.setMax(loader.getFileSize());//设置进度条的最大刻度
    loader.download(new DownloadProgressListener() {
    public void onDownloadSize(int size) {
    Message msg = new Message();
    msg.what = 1;
    msg.getData().putInt("size", size);
    handler.sendMessage(msg);
    }
    });
    } catch (Exception e) {
    e.printStackTrace();
    handler.sendMessage(handler.obtainMessage(-1));
    }
    }
    }
        }
        
        
    }

    DBOpenHelper.java

    import android.content.Context;
    import android.database.sqlite.SQLiteDatabase;
    import android.database.sqlite.SQLiteOpenHelper;

    public class DBOpenHelper extends SQLiteOpenHelper {
    private static final String DBNAME = "itcast.db";
    private static final int VERSION = 1;

    public DBOpenHelper(Context context) {
    super(context, DBNAME, null, VERSION);
    }

    @Override
    public void onCreate(SQLiteDatabase db) {
    db.execSQL("CREATE TABLE IF NOT EXISTS filedownlog (id integer primary key autoincrement, downpath varchar(100), threadid INTEGER, downlength INTEGER)");
    }

    @Override
    public void onUpgrade(SQLiteDatabase db, int oldVersion, int newVersion) {
    db.execSQL("DROP TABLE IF EXISTS filedownlog");
    onCreate(db);
    }
    }

    FileService.java

    import java.util.HashMap;
    import java.util.Map;
    import android.content.Context;
    import android.database.Cursor;
    import android.database.sqlite.SQLiteDatabase;
    /**
     * 业务bean
     *
     */
    public class FileService {
    private DBOpenHelper openHelper;


    public FileService(Context context) {
    openHelper = new DBOpenHelper(context);
    }
    /**
    * 获取每条线程已经下载的文件长度
    * @param path
    * @return
    */
    public Map<Integer, Integer> getData(String path){
    SQLiteDatabase db = openHelper.getReadableDatabase();
    Cursor cursor = db.rawQuery("select threadid, downlength from filedownlog where downpath=?", new String[]{path});
    Map<Integer, Integer> data = new HashMap<Integer, Integer>();
    while(cursor.moveToNext()){
    data.put(cursor.getInt(0), cursor.getInt(1));
    }
    cursor.close();
    db.close();
    return data;
    }
    /**
    * 保存每条线程已经下载的文件长度
    * @param path
    * @param map
    */
    public void save(String path,  Map<Integer, Integer> map){//int threadid, int position
    SQLiteDatabase db = openHelper.getWritableDatabase();
    db.beginTransaction();
    try{
    for(Map.Entry<Integer, Integer> entry : map.entrySet()){
    db.execSQL("insert into filedownlog(downpath, threadid, downlength) values(?,?,?)",
    new Object[]{path, entry.getKey(), entry.getValue()});
    }
    db.setTransactionSuccessful();
    }finally{
    db.endTransaction();
    }
    db.close();
    }
    /**
    * 实时更新每条线程已经下载的文件长度
    * @param path
    * @param map
    */
    public void update(String path, int threadId, int pos){
    SQLiteDatabase db = openHelper.getWritableDatabase();
    db.execSQL("update filedownlog set downlength=? where downpath=? and threadid=?",
    new Object[]{pos, path, threadId});
    db.close();
    }
    /**
    * 当文件下载完成后,删除对应的下载记录
    * @param path
    */
    public void delete(String path){
    SQLiteDatabase db = openHelper.getWritableDatabase();
    db.execSQL("delete from filedownlog where downpath=?", new Object[]{path});
    db.close();
    }

    }

    DownloadProgressListener.java

    public interface DownloadProgressListener {
    public void onDownloadSize(int size);
    }

    DownloadThread.java

    import java.io.File;
    import java.io.InputStream;
    import java.io.RandomAccessFile;
    import java.net.HttpURLConnection;
    import java.net.URL;
    import android.util.Log;

    public class DownloadThread extends Thread {
    private static final String TAG = "DownloadThread";
    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 FileDownloader downloader;

    public DownloadThread(FileDownloader 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 (!downloader.getExit() && (offset = inStream.read(buffer, 0, 1024)) != -1) {
    threadfile.write(buffer, 0, offset);
    downLength += offset;
    downloader.update(this.threadId, downLength);
    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;
    }
    }

    FileDownloader.java

    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 cn.itcast.service.FileService;


    import android.content.Context;
    import android.util.Log;
    /**
     * 文件下载器
     * 
    try {
    FileDownloader loader = new FileDownloader(context, "http://browse.babasport.com/ejb3/ActivePort.exe",
    new File("D:\\androidsoft\\test"), 2);
    loader.getFileSize();//得到文件总大小
    loader.download(new DownloadProgressListener(){
    public void onDownloadSize(int size) {
    print("已经下载:"+ size);
    }
    });
    } catch (Exception e) {
    e.printStackTrace();
    }
     */
    public class FileDownloader {
    private static final String TAG = "FileDownloader";
    private Context context;
    private FileService fileService;
    /* 停止下载 */
    private boolean exit;
    /* 已下载文件长度 */
    private int downloadSize = 0;
    /* 原始文件长度 */
    private int fileSize = 0;
    /* 线程数 */
    private DownloadThread[] 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;
    /**
    * 获取线程数
    */
    public int getThreadSize() {
    return threads.length;
    }
    /**
    * 退出下载
    */
    public void exit(){
    this.exit = true;
    }
    public boolean getExit(){
    return this.exit;
    }
    /**
    * 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 synchronized void update(int threadId, int pos) {
    this.data.put(threadId, pos);
    this.fileService.update(this.downloadUrl, threadId, pos);
    }
    /**
    * 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 FileDownloader(Context context, String downloadUrl, File fileSaveDir, int threadNum) {
    try {
    this.context = context;
    this.downloadUrl = downloadUrl;
    fileService = new FileService(this.context);
    URL url = new URL(this.downloadUrl);
    if(!fileSaveDir.exists()) fileSaveDir.mkdirs();
    this.threads = new DownloadThread[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 ");

    String filename = getFileName(conn);//获取文件名称
    this.saveFile = new File(fileSaveDir, filename);//构建保存文件
    Map<Integer, Integer> logdata = fileService.getData(downloadUrl);//获取下载记录
    if(logdata.size()>0){//如果存在下载记录
    for(Map.Entry<Integer, Integer> entry : logdata.entrySet())
    data.put(entry.getKey(), entry.getValue());//把各条线程已经下载的数据长度放入data中
    }
    if(this.data.size()==this.threads.length){//下面计算所有线程已经下载的数据总长度
    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);
    }
    //计算每条线程下载的数据长度
    this.block = (this.fileSize % this.threads.length)==0? this.fileSize / this.threads.length : this.fileSize / this.threads.length + 1;
    }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);
    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);
    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(DownloadProgressListener 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){//如果原先未曾下载或者原先的下载线程数与现在的线程数不一致
    this.data.clear();
    for (int i = 0; i < this.threads.length; i++) {
    this.data.put(i+1, 0);//初始化每条线程已经下载的数据长度为0
    }
    this.downloadSize = 0;
    }
    for (int i = 0; i < this.threads.length; i++) {//开启线程进行下载
    int downLength = this.data.get(i+1);
    if(downLength < this.block && this.downloadSize<this.fileSize){//判断线程是否已经完成下载,否则继续下载
    this.threads[i] = new DownloadThread(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;
    }
    }
    fileService.delete(this.downloadUrl);//如果存在下载记录,删除它们,然后重新添加
    fileService.save(this.downloadUrl, this.data);
    boolean notFinish = true;//下载未完成
    while (notFinish) {// 循环判断所有线程是否完成下载
    Thread.sleep(900);
    notFinish = false;//假定全部线程下载完成
    for (int i = 0; i < this.threads.length; i++){
    if (this.threads[i] != null && !this.threads[i].isFinish()) {//如果发现线程未完成下载
    notFinish = true;//设置标志为下载没有完成
    if(this.threads[i].getDownLength() == -1){//如果下载失败,再重新下载
    this.threads[i] = new DownloadThread(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);//通知目前已经下载完成的数据长度
    }
    if(downloadSize == this.fileSize) fileService.delete(this.downloadUrl);//下载完成删除记录
    } catch (Exception e) {
    print(e.toString());
    throw new Exception("file download error");
    }
    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());
    }
    }


    private static void print(String msg){
    Log.i(TAG, msg);
    }
    }

    路漫漫其修远兮 吾将上下而求索
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  • 原文地址:https://www.cnblogs.com/hudabing/p/3109853.html
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