oni2/httpfiledownloader/FileDownloader.java

package net.oni2.httpfiledownloader;

import java.io.BufferedInputStream;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.RandomAccessFile;
import java.net.URL;
import java.net.URLConnection;
import java.util.HashSet;

import net.oni2.ProxySettings;

/**
 * @author Christian Illy
 */
public class FileDownloader implements Runnable {
        /**
         * @author Christian Illy
         */
        public enum EState {
                /**
                 * Downloader initialized but not started
                 */
                INIT,
                /**
                 * Download running
                 */
                RUNNING,
                /**
                 * Download suspended
                 */
                PAUSED,
                /**
                 * Download interrupted
                 */
                INTERRUPTED,
                /**
                 * Download finished successfully
                 */
                FINISHED,
                /**
                 * Aborted because of an error
                 */
                ERROR
        };

        private HashSet<FileDownloadListener> listeners = new HashSet<FileDownloadListener>();
        private Thread t = null;
        private URL url = null;
        private File target = null;
        private int fileLength = Integer.MAX_VALUE;
        private int downloaded = 0;

        private EState state = EState.INIT;

        /**
         * @param url
         *            URL of file to download
         * @param target
         *            Path of target file to save to
         * @throws IOException
         *             If url could not be opened
         */
        public FileDownloader(String url, File target) throws IOException {
                this.url = new URL(url);
                this.target = target;
        }

        /**
         * @param listener
         *            Listener to add
         */
        public void addListener(FileDownloadListener listener) {
                listeners.add(listener);
        }

        /**
         * @param listener
         *            Listener to remove
         */
        public void removeListener(FileDownloadListener listener) {
                listeners.remove(listener);
        }

        /**
         * Start the download process
         */
        public synchronized void start() {
                if (t == null) {
                        state = EState.RUNNING;
                        t = new Thread(this);
                        t.start();
                }
        }

        /**
         * @param suspend
         *            Suspend or resume
         */
        public synchronized void suspend(boolean suspend) {
                if ((state == EState.RUNNING) || (state == EState.PAUSED)) {
                        if (suspend)
                                state = EState.PAUSED;
                        else
                                state = EState.RUNNING;
                        updateStatus(downloaded, fileLength);
                }
        }

        /**
         * Stop (abort) download
         */
        public synchronized void stop() {
                if (state != EState.FINISHED) {
                        state = EState.INTERRUPTED;
                        if (t != null) {
                                try {
                                        t.join();
                                } catch (InterruptedException e) {
                                        e.printStackTrace();
                                }
                                t = null;
                        }
                        updateStatus(0, 1);
                        if (target.exists())
                                target.delete();
                }
        }

        /**
         * @return current state
         */
        public EState getState() {
                return state;
        }

        private synchronized void updateStatus(int current, int total) {
                downloaded = current;
                for (FileDownloadListener l : listeners) {
                        l.statusUpdate(this, state, current, total);
                }
        }

        @Override
        public void run() {
                int downloaded = 0;
                String strLastModified = null;
                String strEtag = null;
                RandomAccessFile outFile = null;

                try {
                        outFile = new RandomAccessFile(target, "rw");
                } catch (FileNotFoundException e1) {
                        e1.printStackTrace();
                        state = EState.ERROR;
                        updateStatus(downloaded, fileLength);
                        return;
                }

                try {
                        while (downloaded < fileLength) {
                                switch (state) {
                                        case ERROR:
                                                updateStatus(downloaded, fileLength);
                                                return;
                                        case PAUSED:
                                                try {
                                                        Thread.sleep(100);
                                                } catch (InterruptedException e) {
                                                        e.printStackTrace();
                                                }
                                                break;
                                        case INTERRUPTED:
                                                return;
                                        case RUNNING:
                                                BufferedInputStream input = null;
                                                try {
                                                        URLConnection connection = url
                                                                        .openConnection(ProxySettings.getInstance()
                                                                                        .getProxy());
                                                        connection.setRequestProperty("Cache-Control",
                                                                        "no-cache");
                                                        if (downloaded == 0) {
                                                                connection.connect();
                                                                strLastModified = connection
                                                                                .getHeaderField("Last-Modified");
                                                                strEtag = connection.getHeaderField("ETag");
                                                                fileLength = connection.getContentLength();
                                                        } else {
                                                                connection.setRequestProperty("Range", "bytes="
                                                                                + downloaded + "-");
                                                                if (strEtag != null)
                                                                        connection.setRequestProperty("If-Range",
                                                                                        strEtag);
                                                                else
                                                                        connection.setRequestProperty("If-Range",
                                                                                        strLastModified);
                                                                connection.connect();
                                                        }

                                                        // Setup streams and buffers.
                                                        input = new BufferedInputStream(
                                                                        connection.getInputStream(), 8192);
                                                        if (downloaded > 0)
                                                                outFile.seek(downloaded);
                                                        byte data[] = new byte[1024];

                                                        // Download file.
                                                        int dataRead = 0;
                                                        int i = 0;
                                                        while (((dataRead = input.read(data, 0, 1024)) != -1)
                                                                        && (state == EState.RUNNING)) {
                                                                outFile.write(data, 0, dataRead);
                                                                downloaded += dataRead;
                                                                if (downloaded >= fileLength)
                                                                        break;

                                                                i++;
                                                                if ((i % 50) == 0)
                                                                        updateStatus(downloaded, fileLength);
                                                        }
                                                        input.close();
                                                } catch (IOException e) {
                                                        // TODO Auto-generated catch block
                                                        e.printStackTrace();
                                                        try {
                                                                if (input != null)
                                                                        input.close();
                                                        } catch (IOException e2) {
                                                                e2.printStackTrace();
                                                        }
                                                }
                                                break;
                                        default:
                                                break;
                                }
                        }
                } finally {
                        try {
                                // Close streams.
                                outFile.close();
                        } catch (IOException e) {
                                e.printStackTrace();
                        }
                }

                state = EState.FINISHED;
                updateStatus(downloaded, fileLength);
        }

        /**
         * @return the target
         */
        public File getTarget() {
                return target;
        }

        /**
         * @return the downloaded size
         */
        public int getDownloaded() {
                return downloaded;
        }

}
Revision:	852
Committed:	Fri May 3 12:25:21 2013 UTC (12 years, 6 months ago) by alloc
Content type:	text/x-java
File size:	5619 byte(s)
Log Message:	AEI2.08, AEIUpdater: - Fixes #3
#	Content
1	package net.oni2.httpfiledownloader;
2
3	import java.io.BufferedInputStream;
4	import java.io.File;
5	import java.io.FileNotFoundException;
6	import java.io.IOException;
7	import java.io.RandomAccessFile;
8	import java.net.URL;
9	import java.net.URLConnection;
10	import java.util.HashSet;
11
12	import net.oni2.ProxySettings;
13
14	/**
15	* @author Christian Illy
16	*/
17	public class FileDownloader implements Runnable {
18	/**
19	* @author Christian Illy
20	*/
21	public enum EState {
22	/**
23	* Downloader initialized but not started
24	*/
25	INIT,
26	/**
27	* Download running
28	*/
29	RUNNING,
30	/**
31	* Download suspended
32	*/
33	PAUSED,
34	/**
35	* Download interrupted
36	*/
37	INTERRUPTED,
38	/**
39	* Download finished successfully
40	*/
41	FINISHED,
42	/**
43	* Aborted because of an error
44	*/
45	ERROR
46	};
47
48	private HashSet<FileDownloadListener> listeners = new HashSet<FileDownloadListener>();
49	private Thread t = null;
50	private URL url = null;
51	private File target = null;
52	private int fileLength = Integer.MAX_VALUE;
53	private int downloaded = 0;
54
55	private EState state = EState.INIT;
56
57	/**
58	* @param url
59	* URL of file to download
60	* @param target
61	* Path of target file to save to
62	* @throws IOException
63	* If url could not be opened
64	*/
65	public FileDownloader(String url, File target) throws IOException {
66	this.url = new URL(url);
67	this.target = target;
68	}
69
70	/**
71	* @param listener
72	* Listener to add
73	*/
74	public void addListener(FileDownloadListener listener) {
75	listeners.add(listener);
76	}
77
78	/**
79	* @param listener
80	* Listener to remove
81	*/
82	public void removeListener(FileDownloadListener listener) {
83	listeners.remove(listener);
84	}
85
86	/**
87	* Start the download process
88	*/
89	public synchronized void start() {
90	if (t == null) {
91	state = EState.RUNNING;
92	t = new Thread(this);
93	t.start();
94	}
95	}
96
97	/**
98	* @param suspend
99	* Suspend or resume
100	*/
101	public synchronized void suspend(boolean suspend) {
102	if ((state == EState.RUNNING) \|\| (state == EState.PAUSED)) {
103	if (suspend)
104	state = EState.PAUSED;
105	else
106	state = EState.RUNNING;
107	updateStatus(downloaded, fileLength);
108	}
109	}
110
111	/**
112	* Stop (abort) download
113	*/
114	public synchronized void stop() {
115	if (state != EState.FINISHED) {
116	state = EState.INTERRUPTED;
117	if (t != null) {
118	try {
119	t.join();
120	} catch (InterruptedException e) {
121	e.printStackTrace();
122	}
123	t = null;
124	}
125	updateStatus(0, 1);
126	if (target.exists())
127	target.delete();
128	}
129	}
130
131	/**
132	* @return current state
133	*/
134	public EState getState() {
135	return state;
136	}
137
138	private synchronized void updateStatus(int current, int total) {
139	downloaded = current;
140	for (FileDownloadListener l : listeners) {
141	l.statusUpdate(this, state, current, total);
142	}
143	}
144
145	@Override
146	public void run() {
147	int downloaded = 0;
148	String strLastModified = null;
149	String strEtag = null;
150	RandomAccessFile outFile = null;
151
152	try {
153	outFile = new RandomAccessFile(target, "rw");
154	} catch (FileNotFoundException e1) {
155	e1.printStackTrace();
156	state = EState.ERROR;
157	updateStatus(downloaded, fileLength);
158	return;
159	}
160
161	try {
162	while (downloaded < fileLength) {
163	switch (state) {
164	case ERROR:
165	updateStatus(downloaded, fileLength);
166	return;
167	case PAUSED:
168	try {
169	Thread.sleep(100);
170	} catch (InterruptedException e) {
171	e.printStackTrace();
172	}
173	break;
174	case INTERRUPTED:
175	return;
176	case RUNNING:
177	BufferedInputStream input = null;
178	try {
179	URLConnection connection = url
180	.openConnection(ProxySettings.getInstance()
181	.getProxy());
182	connection.setRequestProperty("Cache-Control",
183	"no-cache");
184	if (downloaded == 0) {
185	connection.connect();
186	strLastModified = connection
187	.getHeaderField("Last-Modified");
188	strEtag = connection.getHeaderField("ETag");
189	fileLength = connection.getContentLength();
190	} else {
191	connection.setRequestProperty("Range", "bytes="
192	+ downloaded + "-");
193	if (strEtag != null)
194	connection.setRequestProperty("If-Range",
195	strEtag);
196	else
197	connection.setRequestProperty("If-Range",
198	strLastModified);
199	connection.connect();
200	}
201
202	// Setup streams and buffers.
203	input = new BufferedInputStream(
204	connection.getInputStream(), 8192);
205	if (downloaded > 0)
206	outFile.seek(downloaded);
207	byte data[] = new byte[1024];
208
209	// Download file.
210	int dataRead = 0;
211	int i = 0;
212	while (((dataRead = input.read(data, 0, 1024)) != -1)
213	&& (state == EState.RUNNING)) {
214	outFile.write(data, 0, dataRead);
215	downloaded += dataRead;
216	if (downloaded >= fileLength)
217	break;
218
219	i++;
220	if ((i % 50) == 0)
221	updateStatus(downloaded, fileLength);
222	}
223	input.close();
224	} catch (IOException e) {
225	// TODO Auto-generated catch block
226	e.printStackTrace();
227	try {
228	if (input != null)
229	input.close();
230	} catch (IOException e2) {
231	e2.printStackTrace();
232	}
233	}
234	break;
235	default:
236	break;
237	}
238	}
239	} finally {
240	try {
241	// Close streams.
242	outFile.close();
243	} catch (IOException e) {
244	e.printStackTrace();
245	}
246	}
247
248	state = EState.FINISHED;
249	updateStatus(downloaded, fileLength);
250	}
251
252	/**
253	* @return the target
254	*/
255	public File getTarget() {
256	return target;
257	}
258
259	/**
260	* @return the downloaded size
261	*/
262	public int getDownloaded() {
263	return downloaded;
264	}
265
266	}