1 /**
2 * This file Copyright (c) 2011-2018 Magnolia International
3 * Ltd. (http://www.magnolia-cms.com). All rights reserved.
4 *
5 *
6 * This file is dual-licensed under both the Magnolia
7 * Network Agreement and the GNU General Public License.
8 * You may elect to use one or the other of these licenses.
9 *
10 * This file is distributed in the hope that it will be
11 * useful, but AS-IS and WITHOUT ANY WARRANTY; without even the
12 * implied warranty of MERCHANTABILITY or FITNESS FOR A
13 * PARTICULAR PURPOSE, TITLE, or NONINFRINGEMENT.
14 * Redistribution, except as permitted by whichever of the GPL
15 * or MNA you select, is prohibited.
16 *
17 * 1. For the GPL license (GPL), you can redistribute and/or
18 * modify this file under the terms of the GNU General
19 * Public License, Version 3, as published by the Free Software
20 * Foundation. You should have received a copy of the GNU
21 * General Public License, Version 3 along with this program;
22 * if not, write to the Free Software Foundation, Inc., 51
23 * Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
24 *
25 * 2. For the Magnolia Network Agreement (MNA), this file
26 * and the accompanying materials are made available under the
27 * terms of the MNA which accompanies this distribution, and
28 * is available at http://www.magnolia-cms.com/mna.html
29 *
30 * Any modifications to this file must keep this entire header
31 * intact.
32 *
33 */
34 package info.magnolia.cms.filters;
35
36 import info.magnolia.cms.filters.RangeSupportFilter.RangeInfo;
37
38 import java.io.IOException;
39
40 import javax.servlet.ServletOutputStream;
41 import javax.servlet.WriteListener;
42
43 import org.slf4j.Logger;
44 import org.slf4j.LoggerFactory;
45
46 /**
47 * Range limited output stream. Will output only bytes in given range, ignoring the rest.
48 */
49 public class RangedOutputStream extends ServletOutputStream {
50
51 private static final Logger log = LoggerFactory.getLogger(RangedOutputStream.class);
52
53 private final ServletOutputStream out;
54
55 private long writtenCount = 0;
56
57 private final RangeInfo range;
58
59 public RangedOutputStream(ServletOutputStream stream, RangeInfo range) {
60 log.debug("Using ranged stream");
61 out = stream;
62 this.range = range;
63 }
64
65 @Override
66 public void write(int b) throws IOException {
67 if (writtenCount >= range.start && writtenCount <= range.end) {
68 out.write(b);
69 }
70 writtenCount++;
71 }
72
73 @Override
74 public void close() throws IOException {
75 int rangeLen = range.end - range.start;
76 int written = (int) Math.min(rangeLen, writtenCount);
77 log.debug("Closing ranged stream after writing {} bytes into range {} bytes of total {} received bytes", written, rangeLen, writtenCount);
78 super.close();
79 }
80
81 @Override
82 public boolean isReady() {
83 return false;
84 }
85
86 @Override
87 public void setWriteListener(WriteListener writeListener) {
88 throw new UnsupportedOperationException("We don't expect any non blocking call here");
89 }
90 }