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 * @key randomness
28 */
29
30 import java.io.*;
31 import java.nio.ByteBuffer;
32 import java.nio.CharBuffer;
33 import java.nio.channels.*;
34 import java.nio.channels.FileChannel;
35 import java.util.Random;
36
37
38 /**
39 * Testing FileChannel's positional write method.
40 */
41 public class Pwrite {
42
43 private static Random generator = new Random();
44
45 private static File blah;
46
47 public static void main(String[] args) throws Exception {
48 genericTest();
49 testUnwritableChannel();
50 }
51
52 // This test for bug 4862411
53 private static void testUnwritableChannel() throws Exception {
54 File blah = File.createTempFile("blah2", null);
55 blah.deleteOnExit();
56 FileOutputStream fos = new FileOutputStream(blah);
57 fos.write(new byte[128]);
58 fos.close();
59 FileInputStream fis = new FileInputStream(blah);
60 FileChannel fc = fis.getChannel();
61 try {
62 fc.write(ByteBuffer.allocate(256),1);
63 throw new RuntimeException("Expected exception not thrown");
64 } catch(NonWritableChannelException e) {
65 // Correct result
66 } finally {
67 fc.close();
68 blah.delete();
69 }
70 }
71
72 private static void genericTest() throws Exception {
73 StringBuffer sb = new StringBuffer();
74 sb.setLength(4);
75
76 blah = File.createTempFile("blah", null);
77 blah.deleteOnExit();
78 initTestFile(blah);
79
80 RandomAccessFile raf = new RandomAccessFile(blah, "rw");
81 FileChannel c = raf.getChannel();
82
83 for (int x=0; x<100; x++) {
84 long offset = generator.nextInt(1000);
85 ByteBuffer bleck = ByteBuffer.allocateDirect(4);
86
87 // Write known sequence out
88 for (byte i=0; i<4; i++) {
89 bleck.put(i);
90 }
91 bleck.flip();
92 long originalPosition = c.position();
93 int totalWritten = 0;
94 while (totalWritten < 4) {
95 int written = c.write(bleck, offset);
96 if (written < 0)
97 throw new Exception("Read failed");
98 totalWritten += written;
99 }
100
101 long newPosition = c.position();
102
103 // Ensure that file pointer position has not changed
104 if (originalPosition != newPosition)
105 throw new Exception("File position modified");
106
107 // Attempt to read sequence back in
108 bleck = ByteBuffer.allocateDirect(4);
109 originalPosition = c.position();
110 int totalRead = 0;
111 while (totalRead < 4) {
112 int read = c.read(bleck, offset);
113 if (read < 0)
114 throw new Exception("Read failed");
115 totalRead += read;
116 }
117 newPosition = c.position();
118
119 // Ensure that file pointer position has not changed
120 if (originalPosition != newPosition)
121 throw new Exception("File position modified");
122
123 for (byte i=0; i<4; i++) {
124 if (bleck.get(i) != i)
125 throw new Exception("Write test failed");
126 }
127 }
128 c.close();
129 raf.close();
130 blah.delete();
131 }
132
133 /**
134 * Creates file blah:
135 * 0000
136 * 0001
137 * 0002
138 * 0003
139 * .
140 * .
141 * .
142 * 3999
143 *
144 * Blah extends beyond a single page of memory so that the
145 * ability to index into a file of multiple pages is tested.
146 */
147 private static void initTestFile(File blah) throws Exception {
148 FileOutputStream fos = new FileOutputStream(blah);
149 BufferedWriter awriter
150 = new BufferedWriter(new OutputStreamWriter(fos, "8859_1"));
151
152 for(int i=0; i<4000; i++) {
153 String number = new Integer(i).toString();
154 for (int h=0; h<4-number.length(); h++)
155 awriter.write("0");
156 awriter.write(""+i);
157 awriter.newLine();
158 }
159 awriter.flush();
160 awriter.close();
161 }
162 }