Java tutorial
/* * Created by Angel Leon (@gubatron), Alden Torres (aldenml) * Copyright (c) 2011, 2012, FrostWire(TM). All rights reserved. * * This program is free software: you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by * the Free Software Foundation, either version 3 of the License, or * (at your option) any later version. * * This program is distributed in the hope that it will be useful, * but WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License * along with this program. If not, see <http://www.gnu.org/licenses/>. */ package com.bt.download.android.gui.httpserver; import java.io.Closeable; import java.io.FileInputStream; import java.io.IOException; import java.io.OutputStream; import java.util.List; import java.util.logging.Level; import java.util.logging.Logger; import org.apache.http.NameValuePair; import org.apache.http.client.utils.URLEncodedUtils; import sun.net.httpserver.Code; import com.bt.download.android.core.ConfigurationManager; import com.bt.download.android.core.FileDescriptor; import com.bt.download.android.gui.Librarian; import com.bt.download.android.gui.services.Engine; import com.bt.download.android.gui.transfers.PeerHttpUpload; import com.bt.download.android.gui.transfers.TransferManager; import com.sun.net.httpserver.HttpExchange; /** * @author gubatron * @author aldenml * */ class DownloadHandler extends AbstractHandler { private static final Logger LOG = Logger.getLogger(DownloadHandler.class.getName()); @Override public void handle(final HttpExchange exchange) throws IOException { Engine.instance().getThreadPool().execute(new Runnable() { @Override public void run() { try { internalHandler(exchange); } catch (IOException e) { LOG.log(Level.WARNING, "DownloadHandler async handle error", e); } } }); } public void internalHandler(HttpExchange exchange) throws IOException { assertUPnPActive(); OutputStream os = null; FileInputStream fis = null; byte type = -1; int id = -1; PeerHttpUpload upload = null; try { List<NameValuePair> query = URLEncodedUtils.parse(exchange.getRequestURI(), "UTF-8"); for (NameValuePair item : query) { if (item.getName().equals("type")) { type = Byte.parseByte(item.getValue()); } if (item.getName().equals("id")) { id = Integer.parseInt(item.getValue()); } } if (type == -1 || id == -1) { exchange.sendResponseHeaders(Code.HTTP_BAD_REQUEST, 0); return; } if (TransferManager.instance().getActiveUploads() >= ConfigurationManager.instance() .maxConcurrentUploads()) { sendBusyResponse(exchange); return; } FileDescriptor fd = Librarian.instance().getFileDescriptor(type, id); if (fd == null) { throw new IOException("There is no such file shared"); } upload = TransferManager.instance().upload(fd); exchange.getResponseHeaders().add("Content-Type", fd.mime); exchange.sendResponseHeaders(Code.HTTP_OK, fd.fileSize); os = exchange.getResponseBody(); fis = new FileInputStream(fd.filePath); byte[] buffer = new byte[4 * 1024]; int n; int count = 0; while ((n = fis.read(buffer, 0, buffer.length)) != -1) { os.write(buffer, 0, n); upload.addBytesSent(n); if (upload.isCanceled()) { try { throw new IOException("Upload cancelled"); } finally { os.close(); } } count += n; if (count > 4096) { count = 0; Thread.yield(); } } } catch (IOException e) { LOG.log(Level.INFO, "Error uploading file type=" + type + ", id=" + id); throw e; } finally { close(os); close(fis); try { exchange.close(); } catch (Throwable e) { // ignore } if (upload != null) { upload.complete(); } } } private void close(Closeable c) { if (c != null) { try { c.close(); } catch (Throwable e) { // ignore } } } private void sendBusyResponse(HttpExchange exchange) throws IOException { exchange.getResponseHeaders().add("Retry-After", "10"); // retry in 10 seconds exchange.sendResponseHeaders(Code.HTTP_UNAVAILABLE, 0); } }