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comparison src/com/go/trove/io/FileByteData.java @ 0:3dc0c5604566

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Initial checkin of blitz 2.0 fcs - no installer yet.
author Dan Creswell <dan.creswell@gmail.com>
date Sat, 21 Mar 2009 11:00:06 +0000
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-1:000000000000 0:3dc0c5604566
1 /* ====================================================================
2 * Trove - Copyright (c) 1999-2000 Walt Disney Internet Group
3 * ====================================================================
4 * The Tea Software License, Version 1.1
5 *
6 * Copyright (c) 2000 Walt Disney Internet Group. All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 *
15 * 2. Redistributions in binary form must reproduce the above copyright
16 * notice, this list of conditions and the following disclaimer in
17 * the documentation and/or other materials provided with the
18 * distribution.
19 *
20 * 3. The end-user documentation included with the redistribution,
21 * if any, must include the following acknowledgment:
22 * "This product includes software developed by the
23 * Walt Disney Internet Group (http://opensource.go.com/)."
24 * Alternately, this acknowledgment may appear in the software itself,
25 * if and wherever such third-party acknowledgments normally appear.
26 *
27 * 4. The names "Tea", "TeaServlet", "Kettle", "Trove" and "BeanDoc" must
28 * not be used to endorse or promote products derived from this
29 * software without prior written permission. For written
30 * permission, please contact opensource@dig.com.
31 *
32 * 5. Products derived from this software may not be called "Tea",
33 * "TeaServlet", "Kettle" or "Trove", nor may "Tea", "TeaServlet",
34 * "Kettle", "Trove" or "BeanDoc" appear in their name, without prior
35 * written permission of the Walt Disney Internet Group.
36 *
37 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
38 * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
39 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
40 * DISCLAIMED. IN NO EVENT SHALL THE WALT DISNEY INTERNET GROUP OR ITS
41 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
42 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
43 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
44 * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY
45 * OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
46 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
47 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
48 * ====================================================================
49 *
50 * For more information about Tea, please see http://opensource.go.com/.
51 */
52
53 package com.go.trove.io;
54
55 import java.io.OutputStream;
56 import java.io.File;
57 import java.io.RandomAccessFile;
58 import java.io.IOException;
59
60 /******************************************************************************
61 * A ByteData implementation that reads the contents of a file.
62 *
63 * @author Brian S O'Neill
64 * @version
65 * <!--$$Revision: 1.1 $-->, <!--$$JustDate:--> 00/12/06 <!-- $-->
66 */
67 public class FileByteData implements ByteData {
68 private static final Object NULL = new Object();
69
70 private File mFile;
71
72 // Thread-local reference to a RandomAccessFile.
73 private ThreadLocal mRAF = new ThreadLocal();
74
75 public FileByteData(File file) {
76 mFile = file;
77 // Open here so that if file isn't found, error is logged earlier.
78 open();
79 }
80
81 public long getByteCount() throws IOException {
82 // Keep file open to ensure that length doesn't change between call to
83 // getByteCount and writeTo.
84
85 RandomAccessFile raf = open();
86 if (raf == null) {
87 return 0;
88 }
89 else {
90 return raf.length();
91 }
92 }
93
94 public void writeTo(OutputStream out) throws IOException {
95 RandomAccessFile raf = open();
96 if (raf == null) {
97 return;
98 }
99
100 try {
101 long length = raf.length();
102 int bufSize;
103 if (length > 4000) {
104 bufSize = 4000;
105 }
106 else {
107 bufSize = (int)length;
108 }
109
110 byte[] inputBuffer = new byte[bufSize];
111
112 raf.seek(0);
113
114 int readAmount;
115 while ((readAmount = raf.read(inputBuffer, 0, bufSize)) > 0) {
116 out.write(inputBuffer, 0, readAmount);
117 }
118 }
119 finally {
120 try {
121 finalize();
122 }
123 catch (IOException e) {
124 }
125 }
126 }
127
128 public void reset() throws IOException {
129 Object obj = mRAF.get();
130 try {
131 if (obj instanceof RandomAccessFile) {
132 ((RandomAccessFile)obj).close();
133 }
134 }
135 finally {
136 mRAF.set(null);
137 }
138 }
139
140 protected final void finalize() throws IOException {
141 reset();
142 }
143
144 private RandomAccessFile open() {
145 Object obj = mRAF.get();
146 if (obj instanceof RandomAccessFile) {
147 return (RandomAccessFile)obj;
148 }
149 else if (obj == NULL) {
150 return null;
151 }
152
153 RandomAccessFile raf = null;
154
155 try {
156 raf = new RandomAccessFile(mFile, "r");
157 mRAF.set(raf);
158 }
159 catch (IOException e) {
160 mRAF.set(NULL);
161 Thread t = Thread.currentThread();
162 t.getThreadGroup().uncaughtException(t, e);
163 }
164
165 return raf;
166 }
167 }