/
TempFile.java
183 lines (159 loc) · 4.41 KB
/
TempFile.java
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
/*
* Copyright (c) 2010, 2020 Oracle and/or its affiliates. All rights reserved.
*
* This program and the accompanying materials are made available under the
* terms of the Eclipse Public License v. 2.0, which is available at
* http://www.eclipse.org/legal/epl-2.0.
*
* This Source Code may also be made available under the following Secondary
* Licenses when the conditions for such availability set forth in the
* Eclipse Public License v. 2.0 are satisfied: GNU General Public License,
* version 2 with the GNU Classpath Exception, which is available at
* https://www.gnu.org/software/classpath/license.html.
*
* SPDX-License-Identifier: EPL-2.0 OR GPL-2.0 WITH Classpath-exception-2.0
*/
package com.sun.mail.mbox;
import java.util.*;
import java.net.*;
import java.io.*;
import java.security.*;
import com.sun.mail.util.PropUtil;
import jakarta.mail.util.SharedFileInputStream;
/**
* A temporary file used to cache messages.
*/
class TempFile {
private File file; // the temp file name
private WritableSharedFile sf;
/**
* Create a temp file in the specified directory (if not null).
* The file will be deleted when the JVM exits.
*/
public TempFile(File dir) throws IOException {
file = File.createTempFile("mbox.", ".mbox", dir);
// XXX - need JDK 6 to set permissions on the file to owner-only
file.deleteOnExit();
sf = new WritableSharedFile(file);
}
/**
* Return a stream for appending to the temp file.
*/
public AppendStream getAppendStream() throws IOException {
return sf.getAppendStream();
}
/**
* Return a stream for reading from part of the file.
*/
public InputStream newStream(long start, long end) {
return sf.newStream(start, end);
}
public long length() {
return file.length();
}
/**
* Close and remove this temp file.
*/
public void close() {
try {
sf.close();
} catch (IOException ex) {
// ignore it
}
file.delete();
}
protected void finalize() throws Throwable {
try {
close();
} finally {
super.finalize();
}
}
}
/**
* A subclass of SharedFileInputStream that also allows writing.
*/
class WritableSharedFile extends SharedFileInputStream {
private RandomAccessFile raf;
private AppendStream af;
public WritableSharedFile(File file) throws IOException {
super(file);
try {
raf = new RandomAccessFile(file, "rw");
} catch (IOException ex) {
// if anything goes wrong opening the writable file,
// close the readable file too
super.close();
}
}
/**
* Return the writable version of this file.
*/
public RandomAccessFile getWritableFile() {
return raf;
}
/**
* Close the readable and writable files.
*/
public void close() throws IOException {
try {
super.close();
} finally {
raf.close();
}
}
/**
* Update the size of the readable file after writing
* to the file. Updates the length to be the current
* size of the file.
*/
synchronized long updateLength() throws IOException {
datalen = in.length();
af = null;
return datalen;
}
/**
* Return a new AppendStream, but only if one isn't in active use.
*/
public synchronized AppendStream getAppendStream() throws IOException {
if (af != null)
throw new IOException(
"file cache only supports single threaded access");
af = new AppendStream(this);
return af;
}
}
/**
* A stream for writing to the temp file, and when done
* can return a stream for reading the data just written.
* NOTE: We assume that only one thread is writing to the
* file at a time.
*/
class AppendStream extends OutputStream {
private final WritableSharedFile tf;
private RandomAccessFile raf;
private final long start;
private long end;
public AppendStream(WritableSharedFile tf) throws IOException {
this.tf = tf;
raf = tf.getWritableFile();
start = raf.length();
raf.seek(start);
}
public void write(int b) throws IOException {
raf.write(b);
}
public void write(byte[] b) throws IOException {
raf.write(b);
}
public void write(byte[] b, int off, int len) throws IOException {
raf.write(b, off, len);
}
public synchronized void close() throws IOException {
end = tf.updateLength();
raf = null; // no more writing allowed
}
public synchronized InputStream getInputStream() throws IOException {
return tf.newStream(start, end);
}
}