Beispiel #1
0
  private void readJournalLine(String line) throws IOException {
    String[] parts = line.split(" ");
    if (parts.length < 2) {
      throw new IOException("unexpected journal line: " + line);
    }

    String key = parts[1];
    if (parts[0].equals(REMOVE) && parts.length == 2) {
      lruEntries.remove(key);
      return;
    }

    Entry entry = lruEntries.get(key);
    if (entry == null) {
      entry = new Entry(key);
      lruEntries.put(key, entry);
    }

    if (parts[0].equals(CLEAN) && parts.length == 2 + valueCount) {
      entry.readable = true;
      entry.currentEditor = null;
      entry.setLengths(copyOfRange(parts, 2, parts.length));
    } else if (parts[0].equals(DIRTY) && parts.length == 2) {
      entry.currentEditor = new Editor(entry);
    } else if (parts[0].equals(READ) && parts.length == 2) {
      // this work was already done by calling lruEntries.get()
    } else {
      throw new IOException("unexpected journal line: " + line);
    }
  }
 /** 这里我做了更改,当手动放入缓存文件后,需要对缓存文件做一次记录 */
 private void refreshJournal() {
   try {
     File[] entryFiles = directory.listFiles();
     for (File entryFile : entryFiles) {
       if (entryFile.getName().length() < 32) continue;
       String key = entryFile.getName().replace(".0", "");
       Entry entry = lruEntries.get(key);
       // 这个文件不存在journal文件中
       if (entry == null) {
         entry = new Entry(key);
         entry.readable = true;
         entry.setLengths(new String[] {entryFile.length() + ""});
         lruEntries.put(key, entry);
         if (journalWriter == null)
           journalWriter = new BufferedWriter(new FileWriter(journalFile, true), IO_BUFFER_SIZE);
         journalWriter.append(DIRTY + ' ' + entry.key + '\n');
         journalWriter.append(CLEAN + ' ' + key + entry.getLengths() + '\n');
       }
     }
     //			readJournal();
     //			trimToSize();
   } catch (IOException e) {
     e.printStackTrace();
   }
 }
  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;
          fileCount++;
        }
      } 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 || fileCount > maxFileCount || journalRebuildRequired()) {
      executorService.submit(cleanupCallable);
    }
  }
  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);
    }
  }