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.nio.channels.FileChannel;
23
24 /**
25 * Indicates the region of a file to be sent to the remote host.
26 *
27 * @author The Apache MINA Project (dev@mina.apache.org)
28 * @version $Rev: 560320 $, $Date: 2007-07-27 11:12:26 -0600 (Fri, 27 Jul 2007) $,
29 */
30 public interface FileRegion {
31
32 /**
33 * The open <tt>FileChannel<tt> from which data will be read to send to
34 * remote host.
35 *
36 * @return An open <tt>FileChannel<tt>.
37 */
38 FileChannel getFileChannel();
39
40 /**
41 * The current file position from which data will be read.
42 *
43 * @return The current file position.
44 */
45 long getPosition();
46
47 /**
48 * Updates the current file position based on the specified amount. This
49 * increases the value returned by {@link #getPosition()} and
50 * {@link getWrittenBytes} by the given amount and decreases the value
51 * returned by {@link #getCount()} by the given {@code amount}.
52 *
53 * @param amount The new value for the file position.
54 */
55 void update(long amount);
56
57 /**
58 * The number of bytes remaining to be written from the file to the remote
59 * host.
60 *
61 * @return The number of bytes remaining to be written.
62 */
63 long getRemainingBytes();
64
65 /**
66 * The total number of bytes already written.
67 *
68 * @return The total number of bytes already written.
69 */
70 long getWrittenBytes();
71
72 }