1 /*
2 * Copyright (c) 2000, 2010, Oracle and/or its affiliates. All rights reserved.
3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4 *
5 * This code is free software; you can redistribute it and/or modify it
6 * under the terms of the GNU General Public License version 2 only, as
7 * published by the Free Software Foundation.
8 *
9 * This code is distributed in the hope that it will be useful, but WITHOUT
10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
12 * version 2 for more details (a copy is included in the LICENSE file that
13 * accompanied this code).
14 *
15 * You should have received a copy of the GNU General Public License version
16 * 2 along with this work; if not, write to the Free Software Foundation,
17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
18 *
19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
20 * or visit www.oracle.com if you need additional information or have any
21 * questions.
22 */
23
24 /* @test
25 * @bug 4862411
26 * @summary Test positional write method of FileChannel
27 */
28
29 import java.io.*;
30 import java.nio.ByteBuffer;
31 import java.nio.CharBuffer;
32 import java.nio.channels.*;
33 import java.nio.channels.FileChannel;
34 import java.util.Random;
35
36
37 /**
38 * Testing FileChannel's positional write method.
39 */
40 public class Pwrite {
41
42 private static Random generator = new Random();
43
44 private static File blah;
45
46 public static void main(String[] args) throws Exception {
47 genericTest();
48 testUnwritableChannel();
49 }
50
51 // This test for bug 4862411
52 private static void testUnwritableChannel() throws Exception {
53 File blah = File.createTempFile("blah2", null);
54 blah.deleteOnExit();
55 FileOutputStream fos = new FileOutputStream(blah);
56 fos.write(new byte[128]);
57 fos.close();
58 FileInputStream fis = new FileInputStream(blah);
59 FileChannel fc = fis.getChannel();
60 try {
61 fc.write(ByteBuffer.allocate(256),1);
62 throw new RuntimeException("Expected exception not thrown");
63 } catch(NonWritableChannelException e) {
64 // Correct result
65 } finally {
66 fc.close();
67 blah.delete();
68 }
69 }
70
71 private static void genericTest() throws Exception {
72 StringBuffer sb = new StringBuffer();
73 sb.setLength(4);
74
75 blah = File.createTempFile("blah", null);
76 blah.deleteOnExit();
77 initTestFile(blah);
78
79 RandomAccessFile raf = new RandomAccessFile(blah, "rw");
80 FileChannel c = raf.getChannel();
81
82 for (int x=0; x<100; x++) {
83 long offset = generator.nextInt(1000);
84 ByteBuffer bleck = ByteBuffer.allocateDirect(4);
85
86 // Write known sequence out
87 for (byte i=0; i<4; i++) {
88 bleck.put(i);
89 }
90 bleck.flip();
91 long originalPosition = c.position();
92 int totalWritten = 0;
93 while (totalWritten < 4) {
94 int written = c.write(bleck, offset);
95 if (written < 0)
96 throw new Exception("Read failed");
97 totalWritten += written;
98 }
99
100 long newPosition = c.position();
101
102 // Ensure that file pointer position has not changed
103 if (originalPosition != newPosition)
104 throw new Exception("File position modified");
105
106 // Attempt to read sequence back in
107 bleck = ByteBuffer.allocateDirect(4);
108 originalPosition = c.position();
109 int totalRead = 0;
110 while (totalRead < 4) {
111 int read = c.read(bleck, offset);
112 if (read < 0)
113 throw new Exception("Read failed");
114 totalRead += read;
115 }
116 newPosition = c.position();
117
118 // Ensure that file pointer position has not changed
119 if (originalPosition != newPosition)
120 throw new Exception("File position modified");
121
122 for (byte i=0; i<4; i++) {
123 if (bleck.get(i) != i)
124 throw new Exception("Write test failed");
125 }
126 }
127 c.close();
128 raf.close();
129 blah.delete();
130 }
131
132 /**
133 * Creates file blah:
134 * 0000
135 * 0001
136 * 0002
137 * 0003
138 * .
139 * .
140 * .
141 * 3999
142 *
143 * Blah extends beyond a single page of memory so that the
144 * ability to index into a file of multiple pages is tested.
145 */
146 private static void initTestFile(File blah) throws Exception {
147 FileOutputStream fos = new FileOutputStream(blah);
148 BufferedWriter awriter
149 = new BufferedWriter(new OutputStreamWriter(fos, "8859_1"));
150
151 for(int i=0; i<4000; i++) {
152 String number = new Integer(i).toString();
153 for (int h=0; h<4-number.length(); h++)
154 awriter.write("0");
155 awriter.write(""+i);
156 awriter.newLine();
157 }
158 awriter.flush();
159 awriter.close();
160 }
161 }