1 /*
2 * Licensed to the Apache Software Foundation (ASF) under one
3 * or more contributor license agreements. See the NOTICE file
4 * distributed with this work for additional information
5 * regarding copyright ownership. The ASF licenses this file
6 * to you under the Apache License, Version 2.0 (the
7 * "License"); you may not use this file except in compliance
8 * with the License. You may obtain a copy of the License at
9 *
10 * http://www.apache.org/licenses/LICENSE-2.0
11 *
12 * Unless required by applicable law or agreed to in writing,
13 * software distributed under the License is distributed on an
14 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
15 * KIND, either express or implied. See the License for the
16 * specific language governing permissions and limitations
17 * under the License.
18 *
19 */
20 package org.apache.mina.core.file;
21
22 import java.io.IOException;
23 import java.nio.channels.FileChannel;
24
25 /**
26 * Manage a File to be sent to a remote host. We keep a track on the current
27 * position, and the number of already written bytes.
28 *
29 *
30 * @author <a href="http://mina.apache.org">Apache MINA Project</a>
31 */
32 public class DefaultFileRegion implements FileRegion {
33 /** The channel used to manage the file */
34 private final FileChannel channel;
35
36 /** The original position in the file */
37 private final long originalPosition;
38
39 /** The position in teh file */
40 private long position;
41
42 /** The number of bytes remaining to write */
43 private long remainingBytes;
44
45 /**
46 * Creates a new DefaultFileRegion instance
47 *
48 * @param channel The channel mapped over the file
49 * @throws IOException If we had an IO error
50 */
51 public DefaultFileRegion(FileChannel channel) throws IOException {
52 this(channel, 0, channel.size());
53 }
54
55 /**
56 * Creates a new DefaultFileRegion instance
57 *
58 * @param channel The channel mapped over the file
59 * @param position The position in teh file
60 * @param remainingBytes The remaining bytes
61 */
62 public DefaultFileRegion(FileChannel channel, long position, long remainingBytes) {
63 if (channel == null) {
64 throw new IllegalArgumentException("channel can not be null");
65 }
66
67 if (position < 0) {
68 throw new IllegalArgumentException("position may not be less than 0");
69 }
70
71 if (remainingBytes < 0) {
72 throw new IllegalArgumentException("remainingBytes may not be less than 0");
73 }
74
75 this.channel = channel;
76 this.originalPosition = position;
77 this.position = position;
78 this.remainingBytes = remainingBytes;
79 }
80
81 /**
82 * {@inheritDoc}
83 */
84 @Override
85 public long getWrittenBytes() {
86 return position - originalPosition;
87 }
88
89 /**
90 * {@inheritDoc}
91 */
92 @Override
93 public long getRemainingBytes() {
94 return remainingBytes;
95 }
96
97 /**
98 * {@inheritDoc}
99 */
100 @Override
101 public FileChannel getFileChannel() {
102 return channel;
103 }
104
105 /**
106 * {@inheritDoc}
107 */
108 @Override
109 public long getPosition() {
110 return position;
111 }
112
113 /**
114 * {@inheritDoc}
115 */
116 @Override
117 public void update(long value) {
118 position += value;
119 remainingBytes -= value;
120 }
121
122 /**
123 * {@inheritDoc}
124 */
125 @Override
126 public String getFilename() {
127 return null;
128 }
129 }