1/*
2 * Copyright (c) 1997, 2015, 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.  Oracle designates this
8 * particular file as subject to the "Classpath" exception as provided
9 * by Oracle in the LICENSE file that accompanied this code.
10 *
11 * This code is distributed in the hope that it will be useful, but WITHOUT
12 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 * version 2 for more details (a copy is included in the LICENSE file that
15 * accompanied this code).
16 *
17 * You should have received a copy of the GNU General Public License version
18 * 2 along with this work; if not, write to the Free Software Foundation,
19 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
20 *
21 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
22 * or visit www.oracle.com if you need additional information or have any
23 * questions.
24 */
25
26package com.sun.xml.internal.org.jvnet.mimepull;
27
28import java.nio.file.Files;
29import java.nio.file.Path;
30import java.nio.file.StandardCopyOption;
31import java.util.concurrent.TimeUnit;
32
33import java.io.File;
34import java.io.IOException;
35import java.io.RandomAccessFile;
36import java.lang.ref.ReferenceQueue;
37import java.lang.ref.WeakReference;
38import java.util.ArrayList;
39import java.util.List;
40import java.util.concurrent.ScheduledExecutorService;
41import java.util.logging.Level;
42import java.util.logging.Logger;
43
44/**
45 * Removing files based on this
46 * <a href="http://java.sun.com/developer/technicalArticles/javase/finalization/">article</a>
47 *
48 * @author Jitendra Kotamraju
49 */
50final class WeakDataFile extends WeakReference<DataFile> {
51
52    private static final Logger LOGGER = Logger.getLogger(WeakDataFile.class.getName());
53    private static int TIMEOUT = 10; //milliseconds
54    //private static final int MAX_ITERATIONS = 2;
55    private static ReferenceQueue<DataFile> refQueue = new ReferenceQueue<DataFile>();
56    private static List<WeakDataFile> refList = new ArrayList<WeakDataFile>();
57    private final File file;
58    private final RandomAccessFile raf;
59    private static boolean hasCleanUpExecutor = false;
60    static {
61        int delay = 10;
62        try {
63                delay = Integer.getInteger("com.sun.xml.internal.org.jvnet.mimepull.delay", 10);
64        } catch (SecurityException se) {
65            if (LOGGER.isLoggable(Level.CONFIG)) {
66                LOGGER.log(Level.CONFIG, "Cannot read ''{0}'' property, using defaults.",
67                        new Object[] {"com.sun.xml.internal.org.jvnet.mimepull.delay"});
68            }
69        }
70        CleanUpExecutorFactory executorFactory = CleanUpExecutorFactory.newInstance();
71        if (executorFactory!=null) {
72            if (LOGGER.isLoggable(Level.FINE)) {
73                LOGGER.log(Level.FINE, "Initializing clean up executor for MIMEPULL: {0}", executorFactory.getClass().getName());
74            }
75            ScheduledExecutorService scheduler = executorFactory.getScheduledExecutorService();
76            scheduler.scheduleWithFixedDelay(new CleanupRunnable(), delay, delay, TimeUnit.SECONDS);
77            hasCleanUpExecutor = true;
78        }
79    }
80
81    WeakDataFile(DataFile df, File file) {
82        super(df, refQueue);
83        refList.add(this);
84        this.file = file;
85        try {
86            raf = new RandomAccessFile(file, "rw");
87        } catch(IOException ioe) {
88            throw new MIMEParsingException(ioe);
89        }
90        if (!hasCleanUpExecutor) {
91            drainRefQueueBounded();
92        }
93    }
94
95    synchronized void read(long pointer, byte[] buf, int offset, int length ) {
96        try {
97            raf.seek(pointer);
98            raf.readFully(buf, offset, length);
99        } catch(IOException ioe) {
100            throw new MIMEParsingException(ioe);
101        }
102    }
103
104    synchronized long writeTo(long pointer, byte[] data, int offset, int length) {
105        try {
106            raf.seek(pointer);
107            raf.write(data, offset, length);
108            return raf.getFilePointer();    // Update pointer for next write
109        } catch(IOException ioe) {
110            throw new MIMEParsingException(ioe);
111        }
112    }
113
114    void close() {
115        if (LOGGER.isLoggable(Level.FINE)) {
116            LOGGER.log(Level.FINE, "Deleting file = {0}", file.getName());
117        }
118        refList.remove(this);
119        try {
120            raf.close();
121            boolean deleted = file.delete();
122            if (!deleted) {
123                if (LOGGER.isLoggable(Level.INFO)) {
124                    LOGGER.log(Level.INFO, "File {0} was not deleted", file.getAbsolutePath());
125                }
126            }
127        } catch(IOException ioe) {
128            throw new MIMEParsingException(ioe);
129        }
130    }
131
132    void renameTo(File f) {
133        if (LOGGER.isLoggable(Level.FINE)) {
134            LOGGER.log(Level.FINE, "Moving file={0} to={1}", new Object[]{file, f});
135        }
136        refList.remove(this);
137        try {
138            raf.close();
139            Path target = Files.move(file.toPath(), f.toPath(), StandardCopyOption.REPLACE_EXISTING);
140            boolean renamed = f.toPath().equals(target);
141            if (!renamed) {
142                if (LOGGER.isLoggable(Level.INFO)) {
143                    throw new MIMEParsingException("File " + file.getAbsolutePath() +
144                            " was not moved to " + f.getAbsolutePath());
145                }
146            }
147        } catch(IOException ioe) {
148            throw new MIMEParsingException(ioe);
149        }
150
151    }
152
153    static void drainRefQueueBounded() {
154        WeakDataFile weak;
155        while (( weak = (WeakDataFile) refQueue.poll()) != null ) {
156            if (LOGGER.isLoggable(Level.FINE)) {
157                LOGGER.log(Level.FINE, "Cleaning file = {0} from reference queue.", weak.file);
158            }
159            weak.close();
160        }
161    }
162
163private static class CleanupRunnable implements Runnable {
164    @Override
165    public void run() {
166        try {
167            if (LOGGER.isLoggable(Level.FINE)) {
168                LOGGER.log(Level.FINE, "Running cleanup task");
169            }
170                WeakDataFile weak = (WeakDataFile) refQueue.remove(TIMEOUT);
171            while (weak != null) {
172                if (LOGGER.isLoggable(Level.FINE)) {
173                    LOGGER.log(Level.FINE, "Cleaning file = {0} from reference queue.", weak.file);
174                }
175                weak.close();
176                weak = (WeakDataFile) refQueue.remove(TIMEOUT);
177            }
178        } catch (InterruptedException e) {
179        }
180    }
181}
182}
183