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package net.oni2.aeinstaller.backend.network; |
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|
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import java.io.BufferedInputStream; |
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import java.io.File; |
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import java.io.FileNotFoundException; |
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import java.io.IOException; |
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import java.io.RandomAccessFile; |
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import java.net.URL; |
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import java.net.URLConnection; |
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import java.util.HashSet; |
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|
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/** |
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* @author Christian Illy |
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*/ |
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public class FileDownloader implements Runnable { |
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/** |
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* @author Christian Illy |
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*/ |
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public enum EState { |
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/** |
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* Downloader initialized but not started |
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*/ |
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INIT, |
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/** |
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* Download running |
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*/ |
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RUNNING, |
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/** |
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* Download suspended |
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*/ |
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PAUSED, |
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/** |
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* Download interrupted |
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*/ |
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INTERRUPTED, |
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/** |
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* Download finished successfully |
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*/ |
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FINISHED, |
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/** |
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* Aborted because of an error |
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*/ |
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ERROR |
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}; |
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|
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private HashSet<FileDownloadListener> listeners = new HashSet<FileDownloadListener>(); |
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private Thread t = null; |
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private URL url = null; |
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private File target = null; |
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private int size = -1; |
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private int downloaded = 0; |
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|
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private EState state = EState.INIT; |
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|
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/** |
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* @param url |
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* URL of file to download |
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* @param target |
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* Path of target file to save to |
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* @throws IOException |
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* If url could not be opened |
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*/ |
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public FileDownloader(String url, String target) throws IOException { |
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this.url = new URL(url); |
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this.target = new File(target); |
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|
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URLConnection connection = this.url.openConnection(); |
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connection.connect(); |
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size = connection.getContentLength(); |
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} |
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|
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/** |
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* @param listener |
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* Listener to add |
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*/ |
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public void addListener(FileDownloadListener listener) { |
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listeners.add(listener); |
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} |
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|
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/** |
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* @param listener |
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* Listener to remove |
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*/ |
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public void removeListener(FileDownloadListener listener) { |
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listeners.remove(listener); |
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} |
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|
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/** |
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* Start the download process |
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*/ |
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public synchronized void start() { |
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if (t == null) { |
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t = new Thread(this); |
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t.start(); |
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state = EState.RUNNING; |
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updateStatus(downloaded, size); |
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} |
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} |
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|
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/** |
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* @param suspend |
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* Suspend or resume |
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*/ |
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public synchronized void suspend(boolean suspend) { |
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if ((state == EState.RUNNING) || (state == EState.PAUSED)) { |
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if (suspend) |
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state = EState.PAUSED; |
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else |
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state = EState.RUNNING; |
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updateStatus(downloaded, size); |
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} |
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} |
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|
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/** |
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* Stop (abort) download |
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*/ |
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public synchronized void stop() { |
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if (state != EState.FINISHED) { |
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state = EState.INTERRUPTED; |
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if (t != null) { |
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try { |
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t.join(); |
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} catch (InterruptedException e) { |
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// TODO Auto-generated catch block |
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e.printStackTrace(); |
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} |
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t = null; |
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} |
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updateStatus(0, 1); |
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if (target.exists()) |
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target.delete(); |
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} |
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} |
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|
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private synchronized void updateStatus(int current, int total) { |
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downloaded = current; |
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for (FileDownloadListener l : listeners) { |
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l.statusUpdate(this, state, current, total); |
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} |
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} |
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|
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@Override |
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public void run() { |
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int downloaded = 0; |
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int fileLength = Integer.MAX_VALUE; |
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String strLastModified = null; |
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String strEtag = null; |
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RandomAccessFile outFile = null; |
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try { |
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outFile = new RandomAccessFile(target, "rw"); |
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} catch (FileNotFoundException e1) { |
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// TODO Auto-generated catch block |
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e1.printStackTrace(); |
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state = EState.ERROR; |
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updateStatus(downloaded, fileLength); |
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return; |
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} |
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|
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try { |
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while (downloaded < fileLength) { |
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switch (state) { |
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case ERROR: |
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updateStatus(downloaded, fileLength); |
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return; |
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case PAUSED: |
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try { |
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Thread.sleep(100); |
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} catch (InterruptedException e) { |
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e.printStackTrace(); |
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} |
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break; |
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case INTERRUPTED: |
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return; |
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case RUNNING: |
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BufferedInputStream input = null; |
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try { |
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URLConnection connection = url.openConnection(); |
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if (downloaded == 0) { |
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connection.connect(); |
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strLastModified = connection |
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.getHeaderField("Last-Modified"); |
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strEtag = connection.getHeaderField("ETag"); |
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fileLength = connection.getContentLength(); |
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} else { |
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connection.setRequestProperty("Range", "bytes=" |
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+ downloaded + "-"); |
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if (strEtag != null) |
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connection.setRequestProperty("If-Range", |
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strEtag); |
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else |
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connection.setRequestProperty("If-Range", |
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strLastModified); |
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connection.connect(); |
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} |
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|
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// Setup streams and buffers. |
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input = new BufferedInputStream( |
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connection.getInputStream(), 8192); |
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if (downloaded > 0) |
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outFile.seek(downloaded); |
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byte data[] = new byte[1024]; |
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|
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// Download file. |
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int dataRead = 0; |
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int i = 0; |
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while (((dataRead = input.read(data, 0, 1024)) != -1) |
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&& (state == EState.RUNNING)) { |
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outFile.write(data, 0, dataRead); |
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downloaded += dataRead; |
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if (downloaded >= fileLength) |
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break; |
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|
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i++; |
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if ((i % 10) == 0) |
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updateStatus(downloaded, fileLength); |
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} |
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input.close(); |
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} catch (IOException e) { |
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// TODO Auto-generated catch block |
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e.printStackTrace(); |
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try { |
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if (input != null) |
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input.close(); |
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} catch (IOException e2) { |
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e2.printStackTrace(); |
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} |
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} |
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break; |
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default: |
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break; |
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} |
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} |
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} finally { |
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try { |
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// Close streams. |
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outFile.close(); |
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} catch (IOException e) { |
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e.printStackTrace(); |
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} |
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} |
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|
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state = EState.FINISHED; |
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updateStatus(downloaded, fileLength); |
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} |
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|
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/** |
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* @return the target |
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*/ |
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public File getTarget() { |
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return target; |
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} |
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|
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/** |
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* @return the size |
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*/ |
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public int getSize() { |
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return size; |
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} |
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|
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/** |
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* @return the downloaded size |
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*/ |
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public int getDownloaded() { |
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return downloaded; |
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} |
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|
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} |