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Diffstat (limited to 'mobile/android/thirdparty/com/jakewharton/disklrucache/DiskLruCache.java')
| -rw-r--r-- | mobile/android/thirdparty/com/jakewharton/disklrucache/DiskLruCache.java | 943 |
1 files changed, 0 insertions, 943 deletions
diff --git a/mobile/android/thirdparty/com/jakewharton/disklrucache/DiskLruCache.java b/mobile/android/thirdparty/com/jakewharton/disklrucache/DiskLruCache.java deleted file mode 100644 index e81e7fbcc..000000000 --- a/mobile/android/thirdparty/com/jakewharton/disklrucache/DiskLruCache.java +++ /dev/null @@ -1,943 +0,0 @@ -/* - * Copyright (C) 2011 The Android Open Source Project - * - * Licensed under the Apache License, Version 2.0 (the "License"); - * you may not use this file except in compliance with the License. - * You may obtain a copy of the License at - * - * http://www.apache.org/licenses/LICENSE-2.0 - * - * Unless required by applicable law or agreed to in writing, software - * distributed under the License is distributed on an "AS IS" BASIS, - * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. - * See the License for the specific language governing permissions and - * limitations under the License. - */ - -package com.jakewharton.disklrucache; - -import java.io.BufferedWriter; -import java.io.Closeable; -import java.io.EOFException; -import java.io.File; -import java.io.FileInputStream; -import java.io.FileNotFoundException; -import java.io.FileOutputStream; -import java.io.FilterOutputStream; -import java.io.IOException; -import java.io.InputStream; -import java.io.InputStreamReader; -import java.io.OutputStream; -import java.io.OutputStreamWriter; -import java.io.Writer; -import java.util.ArrayList; -import java.util.Iterator; -import java.util.LinkedHashMap; -import java.util.Map; -import java.util.concurrent.Callable; -import java.util.concurrent.LinkedBlockingQueue; -import java.util.concurrent.ThreadPoolExecutor; -import java.util.concurrent.TimeUnit; -import java.util.regex.Matcher; -import java.util.regex.Pattern; - -/** - * A cache that uses a bounded amount of space on a filesystem. Each cache - * entry has a string key and a fixed number of values. Each key must match - * the regex <strong>[a-z0-9_-]{1,120}</strong>. Values are byte sequences, - * accessible as streams or files. Each value must be between {@code 0} and - * {@code Integer.MAX_VALUE} bytes in length. - * - * <p>The cache stores its data in a directory on the filesystem. This - * directory must be exclusive to the cache; the cache may delete or overwrite - * files from its directory. It is an error for multiple processes to use the - * same cache directory at the same time. - * - * <p>This cache limits the number of bytes that it will store on the - * filesystem. When the number of stored bytes exceeds the limit, the cache will - * remove entries in the background until the limit is satisfied. The limit is - * not strict: the cache may temporarily exceed it while waiting for files to be - * deleted. The limit does not include filesystem overhead or the cache - * journal so space-sensitive applications should set a conservative limit. - * - * <p>Clients call {@link #edit} to create or update the values of an entry. An - * entry may have only one editor at one time; if a value is not available to be - * edited then {@link #edit} will return null. - * <ul> - * <li>When an entry is being <strong>created</strong> it is necessary to - * supply a full set of values; the empty value should be used as a - * placeholder if necessary. - * <li>When an entry is being <strong>edited</strong>, it is not necessary - * to supply data for every value; values default to their previous - * value. - * </ul> - * Every {@link #edit} call must be matched by a call to {@link Editor#commit} - * or {@link Editor#abort}. Committing is atomic: a read observes the full set - * of values as they were before or after the commit, but never a mix of values. - * - * <p>Clients call {@link #get} to read a snapshot of an entry. The read will - * observe the value at the time that {@link #get} was called. Updates and - * removals after the call do not impact ongoing reads. - * - * <p>This class is tolerant of some I/O errors. If files are missing from the - * filesystem, the corresponding entries will be dropped from the cache. If - * an error occurs while writing a cache value, the edit will fail silently. - * Callers should handle other problems by catching {@code IOException} and - * responding appropriately. - */ -public final class DiskLruCache implements Closeable { - static final String JOURNAL_FILE = "journal"; - static final String JOURNAL_FILE_TEMP = "journal.tmp"; - static final String JOURNAL_FILE_BACKUP = "journal.bkp"; - static final String MAGIC = "libcore.io.DiskLruCache"; - static final String VERSION_1 = "1"; - static final long ANY_SEQUENCE_NUMBER = -1; - static final String STRING_KEY_PATTERN = "[a-z0-9_-]{1,120}"; - static final Pattern LEGAL_KEY_PATTERN = Pattern.compile(STRING_KEY_PATTERN); - private static final String CLEAN = "CLEAN"; - private static final String DIRTY = "DIRTY"; - private static final String REMOVE = "REMOVE"; - private static final String READ = "READ"; - - /* - * This cache uses a journal file named "journal". A typical journal file - * looks like this: - * libcore.io.DiskLruCache - * 1 - * 100 - * 2 - * - * CLEAN 3400330d1dfc7f3f7f4b8d4d803dfcf6 832 21054 - * DIRTY 335c4c6028171cfddfbaae1a9c313c52 - * CLEAN 335c4c6028171cfddfbaae1a9c313c52 3934 2342 - * REMOVE 335c4c6028171cfddfbaae1a9c313c52 - * DIRTY 1ab96a171faeeee38496d8b330771a7a - * CLEAN 1ab96a171faeeee38496d8b330771a7a 1600 234 - * READ 335c4c6028171cfddfbaae1a9c313c52 - * READ 3400330d1dfc7f3f7f4b8d4d803dfcf6 - * - * The first five lines of the journal form its header. They are the - * constant string "libcore.io.DiskLruCache", the disk cache's version, - * the application's version, the value count, and a blank line. - * - * Each of the subsequent lines in the file is a record of the state of a - * cache entry. Each line contains space-separated values: a state, a key, - * and optional state-specific values. - * o DIRTY lines track that an entry is actively being created or updated. - * Every successful DIRTY action should be followed by a CLEAN or REMOVE - * action. DIRTY lines without a matching CLEAN or REMOVE indicate that - * temporary files may need to be deleted. - * o CLEAN lines track a cache entry that has been successfully published - * and may be read. A publish line is followed by the lengths of each of - * its values. - * o READ lines track accesses for LRU. - * o REMOVE lines track entries that have been deleted. - * - * The journal file is appended to as cache operations occur. The journal may - * occasionally be compacted by dropping redundant lines. A temporary file named - * "journal.tmp" will be used during compaction; that file should be deleted if - * it exists when the cache is opened. - */ - - private final File directory; - private final File journalFile; - private final File journalFileTmp; - private final File journalFileBackup; - private final int appVersion; - private long maxSize; - private final int valueCount; - private long size = 0; - private Writer journalWriter; - private final LinkedHashMap<String, Entry> lruEntries = - new LinkedHashMap<String, Entry>(0, 0.75f, true); - private int redundantOpCount; - - /** - * To differentiate between old and current snapshots, each entry is given - * a sequence number each time an edit is committed. A snapshot is stale if - * its sequence number is not equal to its entry's sequence number. - */ - private long nextSequenceNumber = 0; - - /** This cache uses a single background thread to evict entries. */ - final ThreadPoolExecutor executorService = - new ThreadPoolExecutor(0, 1, 60L, TimeUnit.SECONDS, new LinkedBlockingQueue<Runnable>()); - private final Callable<Void> cleanupCallable = new Callable<Void>() { - public Void call() throws Exception { - synchronized (DiskLruCache.this) { - if (journalWriter == null) { - return null; // Closed. - } - trimToSize(); - if (journalRebuildRequired()) { - rebuildJournal(); - redundantOpCount = 0; - } - } - return null; - } - }; - - private DiskLruCache(File directory, int appVersion, int valueCount, long maxSize) { - this.directory = directory; - this.appVersion = appVersion; - this.journalFile = new File(directory, JOURNAL_FILE); - this.journalFileTmp = new File(directory, JOURNAL_FILE_TEMP); - this.journalFileBackup = new File(directory, JOURNAL_FILE_BACKUP); - this.valueCount = valueCount; - this.maxSize = maxSize; - } - - /** - * Opens the cache in {@code directory}, creating a cache if none exists - * there. - * - * @param directory a writable directory - * @param valueCount the number of values per cache entry. Must be positive. - * @param maxSize the maximum number of bytes this cache should use to store - * @throws IOException if reading or writing the cache directory fails - */ - public static DiskLruCache open(File directory, int appVersion, int valueCount, long maxSize) - throws IOException { - if (maxSize <= 0) { - throw new IllegalArgumentException("maxSize <= 0"); - } - if (valueCount <= 0) { - throw new IllegalArgumentException("valueCount <= 0"); - } - - // If a bkp file exists, use it instead. - File backupFile = new File(directory, JOURNAL_FILE_BACKUP); - if (backupFile.exists()) { - File journalFile = new File(directory, JOURNAL_FILE); - // If journal file also exists just delete backup file. - if (journalFile.exists()) { - backupFile.delete(); - } else { - renameTo(backupFile, journalFile, false); - } - } - - // Prefer to pick up where we left off. - DiskLruCache cache = new DiskLruCache(directory, appVersion, valueCount, maxSize); - if (cache.journalFile.exists()) { - try { - cache.readJournal(); - cache.processJournal(); - return cache; - } catch (IOException journalIsCorrupt) { - System.out - .println("DiskLruCache " - + directory - + " is corrupt: " - + journalIsCorrupt.getMessage() - + ", removing"); - cache.delete(); - } - } - - // Create a new empty cache. - directory.mkdirs(); - cache = new DiskLruCache(directory, appVersion, valueCount, maxSize); - cache.rebuildJournal(); - return cache; - } - - private void readJournal() throws IOException { - StrictLineReader reader = new StrictLineReader(new FileInputStream(journalFile), Util.US_ASCII); - try { - String magic = reader.readLine(); - String version = reader.readLine(); - String appVersionString = reader.readLine(); - String valueCountString = reader.readLine(); - String blank = reader.readLine(); - if (!MAGIC.equals(magic) - || !VERSION_1.equals(version) - || !Integer.toString(appVersion).equals(appVersionString) - || !Integer.toString(valueCount).equals(valueCountString) - || !"".equals(blank)) { - throw new IOException("unexpected journal header: [" + magic + ", " + version + ", " - + valueCountString + ", " + blank + "]"); - } - - int lineCount = 0; - while (true) { - try { - readJournalLine(reader.readLine()); - lineCount++; - } catch (EOFException endOfJournal) { - break; - } - } - redundantOpCount = lineCount - lruEntries.size(); - - // If we ended on a truncated line, rebuild the journal before appending to it. - if (reader.hasUnterminatedLine()) { - rebuildJournal(); - } else { - journalWriter = new BufferedWriter(new OutputStreamWriter( - new FileOutputStream(journalFile, true), Util.US_ASCII)); - } - } finally { - Util.closeQuietly(reader); - } - } - - private void readJournalLine(String line) throws IOException { - int firstSpace = line.indexOf(' '); - if (firstSpace == -1) { - throw new IOException("unexpected journal line: " + line); - } - - int keyBegin = firstSpace + 1; - int secondSpace = line.indexOf(' ', keyBegin); - final String key; - if (secondSpace == -1) { - key = line.substring(keyBegin); - if (firstSpace == REMOVE.length() && line.startsWith(REMOVE)) { - lruEntries.remove(key); - return; - } - } else { - key = line.substring(keyBegin, secondSpace); - } - - Entry entry = lruEntries.get(key); - if (entry == null) { - entry = new Entry(key); - lruEntries.put(key, entry); - } - - if (secondSpace != -1 && firstSpace == CLEAN.length() && line.startsWith(CLEAN)) { - String[] parts = line.substring(secondSpace + 1).split(" "); - entry.readable = true; - entry.currentEditor = null; - entry.setLengths(parts); - } else if (secondSpace == -1 && firstSpace == DIRTY.length() && line.startsWith(DIRTY)) { - entry.currentEditor = new Editor(entry); - } else if (secondSpace == -1 && firstSpace == READ.length() && line.startsWith(READ)) { - // This work was already done by calling lruEntries.get(). - } else { - throw new IOException("unexpected journal line: " + line); - } - } - - /** - * Computes the initial size and collects garbage as a part of opening the - * cache. Dirty entries are assumed to be inconsistent and will be deleted. - */ - private void processJournal() throws IOException { - deleteIfExists(journalFileTmp); - for (Iterator<Entry> i = lruEntries.values().iterator(); i.hasNext(); ) { - Entry entry = i.next(); - if (entry.currentEditor == null) { - for (int t = 0; t < valueCount; t++) { - size += entry.lengths[t]; - } - } else { - entry.currentEditor = null; - for (int t = 0; t < valueCount; t++) { - deleteIfExists(entry.getCleanFile(t)); - deleteIfExists(entry.getDirtyFile(t)); - } - i.remove(); - } - } - } - - /** - * Creates a new journal that omits redundant information. This replaces the - * current journal if it exists. - */ - private synchronized void rebuildJournal() throws IOException { - if (journalWriter != null) { - journalWriter.close(); - } - - Writer writer = new BufferedWriter( - new OutputStreamWriter(new FileOutputStream(journalFileTmp), Util.US_ASCII)); - try { - writer.write(MAGIC); - writer.write("\n"); - writer.write(VERSION_1); - writer.write("\n"); - writer.write(Integer.toString(appVersion)); - writer.write("\n"); - writer.write(Integer.toString(valueCount)); - writer.write("\n"); - writer.write("\n"); - - for (Entry entry : lruEntries.values()) { - if (entry.currentEditor != null) { - writer.write(DIRTY + ' ' + entry.key + '\n'); - } else { - writer.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n'); - } - } - } finally { - writer.close(); - } - - if (journalFile.exists()) { - renameTo(journalFile, journalFileBackup, true); - } - renameTo(journalFileTmp, journalFile, false); - journalFileBackup.delete(); - - journalWriter = new BufferedWriter( - new OutputStreamWriter(new FileOutputStream(journalFile, true), Util.US_ASCII)); - } - - private static void deleteIfExists(File file) throws IOException { - if (file.exists() && !file.delete()) { - throw new IOException(); - } - } - - private static void renameTo(File from, File to, boolean deleteDestination) throws IOException { - if (deleteDestination) { - deleteIfExists(to); - } - if (!from.renameTo(to)) { - throw new IOException(); - } - } - - /** - * Returns a snapshot of the entry named {@code key}, or null if it doesn't - * exist is not currently readable. If a value is returned, it is moved to - * the head of the LRU queue. - */ - public synchronized Snapshot get(String key) throws IOException { - checkNotClosed(); - validateKey(key); - Entry entry = lruEntries.get(key); - if (entry == null) { - return null; - } - - if (!entry.readable) { - return null; - } - - // Open all streams eagerly to guarantee that we see a single published - // snapshot. If we opened streams lazily then the streams could come - // from different edits. - InputStream[] ins = new InputStream[valueCount]; - try { - for (int i = 0; i < valueCount; i++) { - ins[i] = new FileInputStream(entry.getCleanFile(i)); - } - } catch (FileNotFoundException e) { - // A file must have been deleted manually! - for (int i = 0; i < valueCount; i++) { - if (ins[i] != null) { - Util.closeQuietly(ins[i]); - } else { - break; - } - } - return null; - } - - redundantOpCount++; - journalWriter.append(READ + ' ' + key + '\n'); - if (journalRebuildRequired()) { - executorService.submit(cleanupCallable); - } - - return new Snapshot(key, entry.sequenceNumber, ins, entry.lengths); - } - - /** - * Returns an editor for the entry named {@code key}, or null if another - * edit is in progress. - */ - public Editor edit(String key) throws IOException { - return edit(key, ANY_SEQUENCE_NUMBER); - } - - private synchronized Editor edit(String key, long expectedSequenceNumber) throws IOException { - checkNotClosed(); - validateKey(key); - Entry entry = lruEntries.get(key); - if (expectedSequenceNumber != ANY_SEQUENCE_NUMBER && (entry == null - || entry.sequenceNumber != expectedSequenceNumber)) { - return null; // Snapshot is stale. - } - if (entry == null) { - entry = new Entry(key); - lruEntries.put(key, entry); - } else if (entry.currentEditor != null) { - return null; // Another edit is in progress. - } - - Editor editor = new Editor(entry); - entry.currentEditor = editor; - - // Flush the journal before creating files to prevent file leaks. - journalWriter.write(DIRTY + ' ' + key + '\n'); - journalWriter.flush(); - return editor; - } - - /** Returns the directory where this cache stores its data. */ - public File getDirectory() { - return directory; - } - - /** - * Returns the maximum number of bytes that this cache should use to store - * its data. - */ - public synchronized long getMaxSize() { - return maxSize; - } - - /** - * Changes the maximum number of bytes the cache can store and queues a job - * to trim the existing store, if necessary. - */ - public synchronized void setMaxSize(long maxSize) { - this.maxSize = maxSize; - executorService.submit(cleanupCallable); - } - - /** - * Returns the number of bytes currently being used to store the values in - * this cache. This may be greater than the max size if a background - * deletion is pending. - */ - public synchronized long size() { - return size; - } - - private synchronized void completeEdit(Editor editor, boolean success) throws IOException { - Entry entry = editor.entry; - if (entry.currentEditor != editor) { - throw new IllegalStateException(); - } - - // If this edit is creating the entry for the first time, every index must have a value. - if (success && !entry.readable) { - for (int i = 0; i < valueCount; i++) { - if (!editor.written[i]) { - editor.abort(); - throw new IllegalStateException("Newly created entry didn't create value for index " + i); - } - if (!entry.getDirtyFile(i).exists()) { - editor.abort(); - return; - } - } - } - - for (int i = 0; i < valueCount; i++) { - File dirty = entry.getDirtyFile(i); - if (success) { - if (dirty.exists()) { - File clean = entry.getCleanFile(i); - dirty.renameTo(clean); - long oldLength = entry.lengths[i]; - long newLength = clean.length(); - entry.lengths[i] = newLength; - size = size - oldLength + newLength; - } - } else { - deleteIfExists(dirty); - } - } - - redundantOpCount++; - entry.currentEditor = null; - if (entry.readable | success) { - entry.readable = true; - journalWriter.write(CLEAN + ' ' + entry.key + entry.getLengths() + '\n'); - if (success) { - entry.sequenceNumber = nextSequenceNumber++; - } - } else { - lruEntries.remove(entry.key); - journalWriter.write(REMOVE + ' ' + entry.key + '\n'); - } - journalWriter.flush(); - - if (size > maxSize || journalRebuildRequired()) { - executorService.submit(cleanupCallable); - } - } - - /** - * We only rebuild the journal when it will halve the size of the journal - * and eliminate at least 2000 ops. - */ - private boolean journalRebuildRequired() { - final int redundantOpCompactThreshold = 2000; - return redundantOpCount >= redundantOpCompactThreshold // - && redundantOpCount >= lruEntries.size(); - } - - /** - * Drops the entry for {@code key} if it exists and can be removed. Entries - * actively being edited cannot be removed. - * - * @return true if an entry was removed. - */ - public synchronized boolean remove(String key) throws IOException { - checkNotClosed(); - validateKey(key); - Entry entry = lruEntries.get(key); - if (entry == null || entry.currentEditor != null) { - return false; - } - - for (int i = 0; i < valueCount; i++) { - File file = entry.getCleanFile(i); - if (file.exists() && !file.delete()) { - throw new IOException("failed to delete " + file); - } - size -= entry.lengths[i]; - entry.lengths[i] = 0; - } - - redundantOpCount++; - journalWriter.append(REMOVE + ' ' + key + '\n'); - lruEntries.remove(key); - - if (journalRebuildRequired()) { - executorService.submit(cleanupCallable); - } - - return true; - } - - /** Returns true if this cache has been closed. */ - public synchronized boolean isClosed() { - return journalWriter == null; - } - - private void checkNotClosed() { - if (journalWriter == null) { - throw new IllegalStateException("cache is closed"); - } - } - - /** Force buffered operations to the filesystem. */ - public synchronized void flush() throws IOException { - checkNotClosed(); - trimToSize(); - journalWriter.flush(); - } - - /** Closes this cache. Stored values will remain on the filesystem. */ - public synchronized void close() throws IOException { - if (journalWriter == null) { - return; // Already closed. - } - for (Entry entry : new ArrayList<Entry>(lruEntries.values())) { - if (entry.currentEditor != null) { - entry.currentEditor.abort(); - } - } - trimToSize(); - journalWriter.close(); - journalWriter = null; - } - - private void trimToSize() throws IOException { - while (size > maxSize) { - Map.Entry<String, Entry> toEvict = lruEntries.entrySet().iterator().next(); - remove(toEvict.getKey()); - } - } - - /** - * Closes the cache and deletes all of its stored values. This will delete - * all files in the cache directory including files that weren't created by - * the cache. - */ - public void delete() throws IOException { - close(); - Util.deleteContents(directory); - } - - private void validateKey(String key) { - Matcher matcher = LEGAL_KEY_PATTERN.matcher(key); - if (!matcher.matches()) { - throw new IllegalArgumentException("keys must match regex " - + STRING_KEY_PATTERN + ": \"" + key + "\""); - } - } - - private static String inputStreamToString(InputStream in) throws IOException { - return Util.readFully(new InputStreamReader(in, Util.UTF_8)); - } - - /** A snapshot of the values for an entry. */ - public final class Snapshot implements Closeable { - private final String key; - private final long sequenceNumber; - private final InputStream[] ins; - private final long[] lengths; - - private Snapshot(String key, long sequenceNumber, InputStream[] ins, long[] lengths) { - this.key = key; - this.sequenceNumber = sequenceNumber; - this.ins = ins; - this.lengths = lengths; - } - - /** - * Returns an editor for this snapshot's entry, or null if either the - * entry has changed since this snapshot was created or if another edit - * is in progress. - */ - public Editor edit() throws IOException { - return DiskLruCache.this.edit(key, sequenceNumber); - } - - /** Returns the unbuffered stream with the value for {@code index}. */ - public InputStream getInputStream(int index) { - return ins[index]; - } - - /** Returns the string value for {@code index}. */ - public String getString(int index) throws IOException { - return inputStreamToString(getInputStream(index)); - } - - /** Returns the byte length of the value for {@code index}. */ - public long getLength(int index) { - return lengths[index]; - } - - public void close() { - for (InputStream in : ins) { - Util.closeQuietly(in); - } - } - } - - private static final OutputStream NULL_OUTPUT_STREAM = new OutputStream() { - @Override - public void write(int b) throws IOException { - // Eat all writes silently. Nom nom. - } - }; - - /** Edits the values for an entry. */ - public final class Editor { - private final Entry entry; - private final boolean[] written; - private boolean hasErrors; - private boolean committed; - - private Editor(Entry entry) { - this.entry = entry; - this.written = (entry.readable) ? null : new boolean[valueCount]; - } - - /** - * Returns an unbuffered input stream to read the last committed value, - * or null if no value has been committed. - */ - public InputStream newInputStream(int index) throws IOException { - synchronized (DiskLruCache.this) { - if (entry.currentEditor != this) { - throw new IllegalStateException(); - } - if (!entry.readable) { - return null; - } - try { - return new FileInputStream(entry.getCleanFile(index)); - } catch (FileNotFoundException e) { - return null; - } - } - } - - /** - * Returns the last committed value as a string, or null if no value - * has been committed. - */ - public String getString(int index) throws IOException { - InputStream in = newInputStream(index); - return in != null ? inputStreamToString(in) : null; - } - - /** - * Returns a new unbuffered output stream to write the value at - * {@code index}. If the underlying output stream encounters errors - * when writing to the filesystem, this edit will be aborted when - * {@link #commit} is called. The returned output stream does not throw - * IOExceptions. - */ - public OutputStream newOutputStream(int index) throws IOException { - if (index < 0 || index >= valueCount) { - throw new IllegalArgumentException("Expected index " + index + " to " - + "be greater than 0 and less than the maximum value count " - + "of " + valueCount); - } - synchronized (DiskLruCache.this) { - if (entry.currentEditor != this) { - throw new IllegalStateException(); - } - if (!entry.readable) { - written[index] = true; - } - File dirtyFile = entry.getDirtyFile(index); - FileOutputStream outputStream; - try { - outputStream = new FileOutputStream(dirtyFile); - } catch (FileNotFoundException e) { - // Attempt to recreate the cache directory. - directory.mkdirs(); - try { - outputStream = new FileOutputStream(dirtyFile); - } catch (FileNotFoundException e2) { - // We are unable to recover. Silently eat the writes. - return NULL_OUTPUT_STREAM; - } - } - return new FaultHidingOutputStream(outputStream); - } - } - - /** Sets the value at {@code index} to {@code value}. */ - public void set(int index, String value) throws IOException { - Writer writer = null; - try { - writer = new OutputStreamWriter(newOutputStream(index), Util.UTF_8); - writer.write(value); - } finally { - Util.closeQuietly(writer); - } - } - - /** - * Commits this edit so it is visible to readers. This releases the - * edit lock so another edit may be started on the same key. - */ - public void commit() throws IOException { - if (hasErrors) { - completeEdit(this, false); - remove(entry.key); // The previous entry is stale. - } else { - completeEdit(this, true); - } - committed = true; - } - - /** - * Aborts this edit. This releases the edit lock so another edit may be - * started on the same key. - */ - public void abort() throws IOException { - completeEdit(this, false); - } - - public void abortUnlessCommitted() { - if (!committed) { - try { - abort(); - } catch (IOException ignored) { - } - } - } - - private class FaultHidingOutputStream extends FilterOutputStream { - private FaultHidingOutputStream(OutputStream out) { - super(out); - } - - @Override public void write(int oneByte) { - try { - out.write(oneByte); - } catch (IOException e) { - hasErrors = true; - } - } - - @Override public void write(byte[] buffer, int offset, int length) { - try { - out.write(buffer, offset, length); - } catch (IOException e) { - hasErrors = true; - } - } - - @Override public void close() { - try { - out.close(); - } catch (IOException e) { - hasErrors = true; - } - } - - @Override public void flush() { - try { - out.flush(); - } catch (IOException e) { - hasErrors = true; - } - } - } - } - - private final class Entry { - private final String key; - - /** Lengths of this entry's files. */ - private final long[] lengths; - - /** True if this entry has ever been published. */ - private boolean readable; - - /** The ongoing edit or null if this entry is not being edited. */ - private Editor currentEditor; - - /** The sequence number of the most recently committed edit to this entry. */ - private long sequenceNumber; - - private Entry(String key) { - this.key = key; - this.lengths = new long[valueCount]; - } - - public String getLengths() throws IOException { - StringBuilder result = new StringBuilder(); - for (long size : lengths) { - result.append(' ').append(size); - } - return result.toString(); - } - - /** Set lengths using decimal numbers like "10123". */ - private void setLengths(String[] strings) throws IOException { - if (strings.length != valueCount) { - throw invalidLengths(strings); - } - - try { - for (int i = 0; i < strings.length; i++) { - lengths[i] = Long.parseLong(strings[i]); - } - } catch (NumberFormatException e) { - throw invalidLengths(strings); - } - } - - private IOException invalidLengths(String[] strings) throws IOException { - throw new IOException("unexpected journal line: " + java.util.Arrays.toString(strings)); - } - - public File getCleanFile(int i) { - return new File(directory, key + "." + i); - } - - public File getDirtyFile(int i) { - return new File(directory, key + "." + i + ".tmp"); - } - } -} |