/* * To change this template, choose Tools | Templates * and open the template in the editor. */package biz.tbuy.huliqing.jloading.downloader;import java.io.BufferedInputStream;import java.io.IOException;import java.io.RandomAccessFile;import java.net.URL;import java.net.URLConnection;import java.util.List;/** * * @author huliqing */public class PieceLoader extends Thread{    private Downloader dl;      // 主下載管理    private List<Piece> tasks;  // 任務列表        private byte[] buff = new byte[1024 * 8];   // 緩沖區的大小    private RandomAccessFile out;    private BufferedInputStream in;        private long readBytes; // 當前線程的讀取字節數    private long timeUsed;  // 當前線程在讀取數據時總花費的時間        public PieceLoader(Downloader dl, List<Piece> tasks) {        this.dl = dl;        this.tasks = tasks;    }        /** 獲取當前線程已經下載的字節數 */    public long getReadBytes() {        return readBytes;    }        /** 獲取當前線程讀取數據時總花費的時間 */    public long getTimeUsed() {        return timeUsed;    }        /** 獲取當前線程的下載速度 */    public long getSpeed() {        if (timeUsed <= 0) return 0;        return readBytes / timeUsed;    }        /** 繼續下載任務 */    public synchronized void toContinue() {        this.notifyAll();    }        @Override    public void run() {        while (!dl.isOk()) {                        // 暫停任務            synchronized (this) {                if (dl.isPaused()) {                    try {                        this.wait();                    } catch (InterruptedException e) {                    }                }            }                        // 中斷停止            if (Thread.interrupted() || dl.isStopped()) {                return;            }                        // 等待獲取任務            Piece piece;            synchronized (tasks) {                while (tasks.isEmpty()) {                    if (dl.isOk()) return;                    try {                        tasks.wait();                        //System.out.println(this.getName() + ":wait............");                    } catch (InterruptedException ie) {                        //System.out.println(this.getName() +                         //        ":InterruptedException:" + ie.getMessage());                    }                }                piece = tasks.remove(0);                dl.removeFreeLoader(this);                //System.out.println(this.getName() + ":loading............");            }            try {                URL u = new URL(dl.getURL());                URLConnection uc = u.openConnection();                // 設置斷點續傳位置                uc.setAllowUserInteraction(true);                uc.setRequestProperty("Range", "bytes=" + piece.getPos() + "-" + piece.getEnd());                in = new BufferedInputStream(uc.getInputStream());                out = new RandomAccessFile(dl.getFileProcess(), "rw");                out.seek(piece.getPos()); // 設置指針位置                long start;                long end;                int len = 0;                while (piece.getPos() < piece.getEnd()) {                    start = System.currentTimeMillis();                    len = in.read(buff, 0, buff.length);                    if (len == -1) break;                    out.write(buff, 0, len);                    end = System.currentTimeMillis();                    timeUsed += end - start;    // 累計時間使用                                        long newPos = piece.getPos() + len;                                        // 如果該區段已經完成,如果該線程負責的區域已經完成，或出界                    if (newPos > piece.getEnd()) {                        piece.setPos(piece.getEnd());                           long offset = newPos - piece.getEnd();                        long trueReads = (len - offset + 1);                        dl.growReadBytes(trueReads);    // 修正偏移量                        dl.setOffsetTotal(dl.getOffsetTotal() + trueReads);                        readBytes += trueReads;                        //System.out.println(this.getName() + ":read=" + trueReads);                    } else {                        dl.growReadBytes(len);                        piece.setPos(piece.getPos() + len);                        readBytes += len;                        //System.out.println(this.getName() + ":read=" + len);                    }                    // 如果存在空閑的任務線程，則切割出新的區域至任務隊列中。由空閑                    // 的線程輔助下載                    if (dl.isFreeLoader()) {                        Piece newPiece = piece.cutPiece();                        if (newPiece != null) {                            synchronized (tasks) {                                dl.addTask(newPiece);                                dl.setRepairCount(dl.getRepairCount() + 1); // 增加切割次數                                tasks.notifyAll();  // 喚醒等待任務中的空閑線程                            }                        }                                            }                    // 暫停任務                    synchronized (this) {                        if (dl.isPaused()) {                            try {                                this.wait();                            } catch (InterruptedException e) {                            }                        }                    }                                        // 中斷停止                    if (Thread.interrupted() || dl.isStopped()) {                        in.close();                        out.close();                        return;                    }                    //System.out.println(this.getName() + ":read:" + dl.getReadBytes());                }                out.close();                in.close();                 dl.addFreeLoader(this);                //System.out.println("切割次數：" + dl.getRepairCount());                if (dl.isOk()) dl.processWhenOk();            } catch (IOException e) {                //System.out.println(this.getName() + ":無法讀取數據");            }        }    }    }