Mercurial > jhg

annotate src/org/tmatesoft/hg/internal/ByteArrayDataAccess.java @ 198:33a7d76f067b

Find changesets by keywords (author, files, the commit message), revision number or hash, or revset expression.
Performance optimization: reduce memory to keep revlog cached info
author Artem Tikhomirov <tikhomirov.artem@gmail.com>
date Wed, 20 Apr 2011 05:40:14 +0200
parents b413b16d10a5
children 6c22bdc0bdfd
rev   line source
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
1 /*
157
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
2 * Copyright (c) 2011 TMate Software Ltd
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
3 *
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
4 * This program is free software; you can redistribute it and/or modify
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
5 * it under the terms of the GNU General Public License as published by
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
6 * the Free Software Foundation; version 2 of the License.
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
7 *
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
8 * This program is distributed in the hope that it will be useful,
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
9 * but WITHOUT ANY WARRANTY; without even the implied warranty of
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
10 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
11 * GNU General Public License for more details.
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
12 *
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
13 * For information on how to redistribute this software under
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
14 * the terms of a license other than GNU General Public License
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
15 * contact TMate Software at support@hg4j.com
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
16 */
157
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
17 package org.tmatesoft.hg.internal;
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
18
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
19 import java.io.IOException;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
20
157
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
21
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
22 /**
157
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
23 *
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
24 * @author Artem Tikhomirov
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
25 * @author TMate Software Ltd.
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
26 */
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
27 public class ByteArrayDataAccess extends DataAccess {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
28
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
29 private final byte[] data;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
30 private final int offset;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
31 private final int length;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
32 private int pos;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
33
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
34 public ByteArrayDataAccess(byte[] data) {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
35 this(data, 0, data.length);
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
36 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
37
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
38 public ByteArrayDataAccess(byte[] data, int offset, int length) {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
39 this.data = data;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
40 this.offset = offset;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
41 this.length = length;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
42 pos = 0;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
43 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
44
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
45 @Override
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
46 public byte readByte() throws IOException {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
47 if (pos >= length) {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
48 throw new IOException();
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
49 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
50 return data[offset + pos++];
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
51 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
52 @Override
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
53 public void readBytes(byte[] buf, int off, int len) throws IOException {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
54 if (len > (this.length - pos)) {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
55 throw new IOException();
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
56 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
57 System.arraycopy(data, pos, buf, off, len);
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
58 pos += len;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
59 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
60
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
61 @Override
157
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
62 public ByteArrayDataAccess reset() {
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
63 pos = 0;
157
d5268ca7715b Merged branch wrap-data-access into default for resource-friendly data access. Updated API to promote that friendliness to clients (channels, not byte[]). More exceptions
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 51
diff changeset
64 return this;
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
65 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
66 @Override
158
b413b16d10a5 Integer offsets and file length explictly, rather than casts throughout code. Inflater may benefit from total length hint, but shall calculate it by its own if needed
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 157
diff changeset
67 public int length() {
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
68 return length;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
69 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
70 @Override
158
b413b16d10a5 Integer offsets and file length explictly, rather than casts throughout code. Inflater may benefit from total length hint, but shall calculate it by its own if needed
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents: 157
diff changeset
71 public void seek(int offset) {
51
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
72 pos = (int) offset;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
73 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
74 @Override
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
75 public void skip(int bytes) throws IOException {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
76 seek(pos + bytes);
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
77 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
78 @Override
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
79 public boolean isEmpty() {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
80 return pos >= length;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
81 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
82
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
83 //
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
84
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
85 // when byte[] needed from DA, we may save few cycles and some memory giving this (otherwise unsafe) access to underlying data
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
86 @Override
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
87 public byte[] byteArray() {
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
88 return data;
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
89 }
9429c7bd1920 Try DataAccess to reach revision data instead of plain byte arrays
Artem Tikhomirov <tikhomirov.artem@gmail.com>
parents:
diff changeset
90 }