Esempio n. 1
0
 public void getNextURLs(int max, List<WebURL> result) {
   while (true) {
     synchronized (mutex) {
       if (isFinished) {
         return;
       }
       try {
         List<WebURL> curResults = workQueues.get(max);
         workQueues.delete(curResults.size());
         if (inProcessPages != null) {
           for (WebURL curPage : curResults) {
             inProcessPages.put(curPage);
           }
         }
         result.addAll(curResults);
       } catch (DatabaseException e) {
         logger.error("Error while getting next urls: " + e.getMessage());
         e.printStackTrace();
       }
       if (result.size() > 0) {
         return;
       }
     }
     try {
       synchronized (waitingList) {
         waitingList.wait();
       }
     } catch (InterruptedException ignored) {
       // Do nothing
     }
     if (isFinished) {
       return;
     }
   }
 }
 public void doHook() {
   try {
     EnvironmentImpl envImpl = DbInternal.getEnvironmentImpl(env);
     SingleItemEntry<CheckpointStart> startEntry =
         SingleItemEntry.create(LogEntryType.LOG_CKPT_START, new CheckpointStart(100, "test"));
     long checkpointStart =
         envImpl.getLogManager().log(startEntry, ReplicationContext.NO_REPLICATE);
     CheckpointEnd ckptEnd =
         new CheckpointEnd(
             "test",
             checkpointStart,
             envImpl.getRootLsn(),
             envImpl.getTxnManager().getFirstActiveLsn(),
             envImpl.getNodeSequence().getLastLocalNodeId(),
             envImpl.getNodeSequence().getLastReplicatedNodeId(),
             envImpl.getDbTree().getLastLocalDbId(),
             envImpl.getDbTree().getLastReplicatedDbId(),
             envImpl.getTxnManager().getLastLocalTxnId(),
             envImpl.getTxnManager().getLastReplicatedTxnId(),
             100,
             true /*cleanedFilesToDelete*/,
             envImpl.getCleaner().getLogSummary());
     SingleItemEntry<CheckpointEnd> endEntry =
         SingleItemEntry.create(LogEntryType.LOG_CKPT_END, ckptEnd);
     envImpl
         .getLogManager()
         .logForceFlush(
             endEntry,
             true, // fsyncRequired
             ReplicationContext.NO_REPLICATE);
   } catch (DatabaseException e) {
     fail(e.getMessage());
   }
 }
Esempio n. 3
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 public Frontier(Environment env, CrawlConfig config, DocIDServer docIdServer) {
   super(config);
   this.counters = new Counters(env, config);
   this.docIdServer = docIdServer;
   try {
     workQueues = new WorkQueues(env, "PendingURLsDB", config.isResumableCrawling());
     if (config.isResumableCrawling()) {
       scheduledPages = counters.getValue(ReservedCounterNames.SCHEDULED_PAGES);
       inProcessPages = new InProcessPagesDB(env);
       long numPreviouslyInProcessPages = inProcessPages.getLength();
       if (numPreviouslyInProcessPages > 0) {
         logger.info("Rescheduling " + numPreviouslyInProcessPages + " URLs from previous crawl.");
         scheduledPages -= numPreviouslyInProcessPages;
         while (true) {
           List<WebURL> urls = inProcessPages.get(100);
           if (urls.size() == 0) {
             break;
           }
           scheduleAll(urls);
           inProcessPages.delete(urls.size());
         }
       }
     } else {
       inProcessPages = null;
       scheduledPages = 0;
     }
   } catch (DatabaseException e) {
     logger.error("Error while initializing the Frontier: " + e.getMessage());
     workQueues = null;
   }
 }
Esempio n. 4
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 public void close() {
   try {
     urlsDB.close();
   } catch (DatabaseException e) {
     e.printStackTrace();
   }
 }
Esempio n. 5
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  private void openEnvironment(File file) throws DatabaseInitException {
    EnvironmentConfig envConfig = new EnvironmentConfig();
    envConfig.setCachePercent(30);
    envConfig.setAllowCreate(true);
    envConfig.setTransactional(true);
    envConfig.setTxnTimeout(10, TimeUnit.SECONDS);
    envConfig.setLockTimeout(2000, TimeUnit.MILLISECONDS);
    try {
      environment = new Environment(file, envConfig);
      transactionConfig = new TransactionConfig();
      transactionConfig.setReadCommitted(true);

      cursorConfig = new CursorConfig();
      cursorConfig.setReadCommitted(true);
    } catch (EnvironmentLockedException e) {
      String message =
          "Environment locked exception. Another process is using the same database, or the current user has no write access (database location: \""
              + file.getAbsolutePath()
              + "\")";
      throw new DatabaseInitException(message);
    } catch (DatabaseException e) {
      String message = "A database initialisation error has occured (" + e.getMessage() + ")";
      throw new DatabaseInitException(message);
    }
  }
Esempio n. 6
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 public void remove(String csName) {
   try {
     m_env.removeDatabase(null, csName);
   } catch (DatabaseException e) {
     e.printStackTrace();
   }
   m_env = null;
 }
 /** Closes the database. */
 @Override
 public void close() {
   try {
     database.close();
   } catch (DatabaseException e) {
     LOGGER.error("Ignored: Could not close database: " + e.getMessage());
   }
 }
Esempio n. 8
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 private static void attemptClose(Cursor cursor) {
   try {
     if (cursor != null) cursor.close();
   } catch (DatabaseException e) {
     logger.error("Error closing cursor.", e);
     throw new PersistenceFailureException(e.getMessage(), e);
   }
 }
 /**
  * Method used by BdbFrontier during checkpointing.
  *
  * <p>The backing bdbje database has been marked deferred write so we save on writes to disk.
  * Means no guarantees disk will have whats in memory unless a sync is called (Calling sync on the
  * bdbje Environment is not sufficent).
  *
  * <p>Package access only because only Frontiers of this package would ever need access.
  *
  * @see <a href="http://www.sleepycat.com/jedocs/GettingStartedGuide/DB.html">Deferred Write
  *     Databases</a>
  */
 void sync() {
   if (this.pendingUrisDB == null) {
     return;
   }
   try {
     this.pendingUrisDB.sync();
   } catch (DatabaseException e) {
     e.printStackTrace();
   }
 }
 /* (non-Javadoc)
  * @see de.tudarmstadt.ukp.dkpro.ir.util.berkeleydb.BerkeleyDbEnvironmentResource#close()
  */
 public void close() {
   if (environment != null) {
     try {
       environment.close();
     } catch (DatabaseException e) {
       // TODO use logger instead of out
       e.printStackTrace();
     }
   }
 }
Esempio n. 11
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 protected void deleteItem(final WorkQueueFrontier frontier, final CrawlURI peekItem)
     throws IOException {
   try {
     final BdbMultipleWorkQueues queues = ((BdbFrontier) frontier).getWorkQueues();
     queues.delete(peekItem);
   } catch (DatabaseException e) {
     e.printStackTrace();
     throw IoUtils.wrapAsIOException(e);
   }
 }
  private static void closeEnv() {
    System.out.println("Closing env and databases");
    if (myDb != null) {
      try {
        myDb.close();
      } catch (DatabaseException e) {
        System.err.println("closeEnv: myDb: " + e.toString());
        e.printStackTrace();
      }
    }

    if (myClassDb != null) {
      try {
        myClassDb.close();
      } catch (DatabaseException e) {
        System.err.println("closeEnv: myClassDb: " + e.toString());
        e.printStackTrace();
      }
    }

    if (myEnv != null) {
      try {
        myEnv.close();
      } catch (DatabaseException e) {
        System.err.println("closeEnv: " + e.toString());
        e.printStackTrace();
      }
    }
  }
 public static void main(String args[]) {
   ExampleInventoryRead eir = new ExampleInventoryRead();
   try {
     eir.run(args);
   } catch (DatabaseException dbe) {
     System.err.println("ExampleInventoryRead: " + dbe.toString());
     dbe.printStackTrace();
   } finally {
     myDbEnv.close();
   }
   System.out.println("All done.");
 }
Esempio n. 14
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 public BtreeFile createBtreeFile(String csName) // , boolean bCanSortMultiThreads)
     {
   // Now open, or create and open, the database
   try {
     Database bdb = m_env.openDatabase(null, csName, m_DbConfig);
     BtreeFile btreeFile = new BtreeFile(bdb); // , bCanSortMultiThreads);
     return btreeFile;
   } catch (DatabaseException e) {
     e.printStackTrace();
     return null;
   }
 }
Esempio n. 15
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  /**
   * Set an attribute value for the given environment.
   *
   * @param targetEnv The target JE environment. May be null if the environment is not open.
   * @param attribute name/value pair
   */
  public void setAttribute(Environment targetEnv, Attribute attribute)
      throws AttributeNotFoundException, InvalidAttributeValueException {

    if (attribute == null) {
      throw new AttributeNotFoundException("Attribute cannot be null");
    }

    /* Sanity check parameters. */
    String name = attribute.getName();
    Object value = attribute.getValue();

    if (name == null) {
      throw new AttributeNotFoundException("Attribute name cannot be null");
    }

    if (value == null) {
      throw new InvalidAttributeValueException(
          "Attribute value for attribute " + name + " cannot be null");
    }

    try {
      if (name.equals(ATT_SET_READ_ONLY)) {
        openConfig.setReadOnly(((Boolean) value).booleanValue());
      } else if (name.equals(ATT_SET_TRANSACTIONAL)) {
        openConfig.setTransactional(((Boolean) value).booleanValue());
      } else if (name.equals(ATT_SET_SERIALIZABLE)) {
        openConfig.setTxnSerializableIsolation(((Boolean) value).booleanValue());
      } else {
        /* Set the specified attribute if the environment is open. */
        if (targetEnv != null) {

          EnvironmentMutableConfig config = targetEnv.getMutableConfig();

          if (name.equals(ATT_CACHE_SIZE)) {
            config.setCacheSize(((Long) value).longValue());
            targetEnv.setMutableConfig(config);
          } else if (name.equals(ATT_CACHE_PERCENT)) {
            config.setCachePercent(((Integer) value).intValue());
            targetEnv.setMutableConfig(config);
          } else {
            throw new AttributeNotFoundException("attribute " + name + " is not valid.");
          }
        } else {
          throw new AttributeNotFoundException("attribute " + name + " is not valid.");
        }
      }
    } catch (NumberFormatException e) {
      throw new InvalidAttributeValueException("attribute name=" + name);
    } catch (DatabaseException e) {
      throw new InvalidAttributeValueException("attribute name=" + name + e.getMessage());
    }
  }
Esempio n. 16
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 public void sync() {
   if (resumable) {
     return;
   }
   if (urlsDB == null) {
     return;
   }
   try {
     urlsDB.sync();
   } catch (DatabaseException e) {
     e.printStackTrace();
   }
 }
 public static StateStore.Factory deserialize(Element store) throws XMLParseException {
   String type = store.getAttribute("type");
   if (type.compareToIgnoreCase("hash") == 0) {
     return HashTableStore.Factory.deserialize(store);
   } else if (type.compareToIgnoreCase("bdb") == 0) {
     try {
       return BerkeleyDBStore.Factory.deserialize(store);
     } catch (DatabaseException e) {
       throw new XMLParseException(e.getMessage(), e.getCause());
     }
   }
   throw new XMLParseException("Unrecognized state store type \'" + type + "\'", store);
 }
Esempio n. 18
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  public static void main(String[] args) {
    Environment env = null;
    Database db = null;
    EnvironmentConfig envconfig = new EnvironmentConfig();
    envconfig.setAllowCreate(true);
    try {
      env = new Environment(new File("D://bdb"), envconfig);
      DatabaseConfig dbconfig = new DatabaseConfig();
      dbconfig.setAllowCreate(true);
      db = env.openDatabase(null, "dbac.db", dbconfig);
      String key = "mykey";
      DatabaseEntry thekey = new DatabaseEntry();
      thekey.setData(key.getBytes("utf-8"));

      Long value = new Long(123456);
      DatabaseEntry thevalue = new DatabaseEntry();
      EntryBinding myBinging = TupleBinding.getPrimitiveBinding(Long.class);
      myBinging.objectToEntry(value, thevalue);
      // LongBinding myLongBinging=(LongBinding)TupleBinding.getPrimitiveBinding(Long.class);
      // myLongBinging.objectToEntry(value, thevalue);
      db.put(null, thekey, thevalue);
      DatabaseEntry valueEntry = new DatabaseEntry();
      OperationStatus status = db.get(null, thekey, valueEntry, LockMode.DEFAULT);
      if (status == OperationStatus.SUCCESS) {
        // Long number=myLongBinging.entryToObject(valueEntry);
        Long number = (Long) myBinging.entryToObject(valueEntry);
        System.out.println(env.getDatabaseNames());
        System.out.println(number);
      }
    } catch (EnvironmentLockedException e) {
      e.printStackTrace();
    } catch (Exception e) {
      e.printStackTrace();
    } finally {
      if (db != null) {
        try {
          db.close();
        } catch (DatabaseException e) {
          e.printStackTrace();
        }
      }
      if (env != null) {
        try {
          env.cleanLog();
          env.close();
        } catch (DatabaseException e) {
          e.printStackTrace();
        }
      }
    }
  }
Esempio n. 19
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  /**
   * Invoke an operation for the given environment.
   *
   * @param targetEnv The target JE environment. May be null if the environment is not open.
   * @param actionName operation name.
   * @param params operation parameters. May be null.
   * @param signature operation signature. May be null.
   * @return the operation result
   */
  public Object invoke(
      Environment targetEnv, String actionName, Object[] params, String[] signature)
      throws MBeanException {

    /* Sanity checking. */
    if (actionName == null) {
      throw new IllegalArgumentException("actionName cannot be null");
    }

    try {
      if (targetEnv != null) {
        if (actionName.equals(OP_CLEAN)) {
          int numFiles = targetEnv.cleanLog();
          return new Integer(numFiles);
        } else if (actionName.equals(OP_EVICT)) {
          targetEnv.evictMemory();
          return null;
        } else if (actionName.equals(OP_CHECKPOINT)) {
          CheckpointConfig config = new CheckpointConfig();
          if ((params != null) && (params.length > 0)) {
            Boolean force = (Boolean) params[0];
            config.setForce(force.booleanValue());
          }
          targetEnv.checkpoint(config);
          return null;
        } else if (actionName.equals(OP_SYNC)) {
          targetEnv.sync();
          return null;
        } else if (actionName.equals(OP_ENV_STAT)) {
          return targetEnv.getStats(getStatsConfig(params));
        } else if (actionName.equals(OP_LOCK_STAT)) {
          return targetEnv.getLockStats(getStatsConfig(params));
        } else if (actionName.equals(OP_TXN_STAT)) {
          return targetEnv.getTransactionStats(getStatsConfig(params));
        } else if (actionName.equals(OP_DB_NAMES)) {
          return targetEnv.getDatabaseNames();
        } else if (actionName.equals(OP_DB_STAT)) {
          return getDatabaseStats(targetEnv, params);
        }
      }

      return new IllegalArgumentException("actionName: " + actionName + " is not valid");
    } catch (DatabaseException e) {
      /*
       * Add both the message and the exception for easiest
       * deciphering of the problem. Sometimes the original exception
       * stacktrace gets hidden in server logs.
       */
      throw new MBeanException(e, e.getMessage());
    }
  }
Esempio n. 20
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  /** {@inheritDoc} */
  @Override()
  public void finalizeBackend() {
    // Deregister as a change listener.
    cfg.removeLocalDBChangeListener(this);

    // Deregister our base DNs.
    for (DN dn : rootContainer.getBaseDNs()) {
      try {
        DirectoryServer.deregisterBaseDN(dn);
      } catch (Exception e) {
        if (debugEnabled()) {
          TRACER.debugCaught(DebugLogLevel.ERROR, e);
        }
      }
    }

    DirectoryServer.deregisterMonitorProvider(rootContainerMonitor);
    DirectoryServer.deregisterMonitorProvider(diskMonitor);

    // We presume the server will prevent more operations coming into this
    // backend, but there may be existing operations already in the
    // backend. We need to wait for them to finish.
    waitUntilQuiescent();

    // Close the database.
    try {
      rootContainer.close();
      rootContainer = null;
    } catch (DatabaseException e) {
      if (debugEnabled()) {
        TRACER.debugCaught(DebugLogLevel.ERROR, e);
      }
      Message message = ERR_JEB_DATABASE_EXCEPTION.get(e.getMessage());
      logError(message);
    }

    // Checksum this db environment and register its offline state id/checksum.
    DirectoryServer.registerOfflineBackendStateID(this.getBackendID(), checksumDbEnv());

    // Deregister the alert generator.
    DirectoryServer.deregisterAlertGenerator(this);

    // Make sure the thread counts are zero for next initialization.
    threadTotalCount.set(0);
    threadWriteCount.set(0);

    // Log an informational message.
    Message message = NOTE_BACKEND_OFFLINE.get(cfg.getBackendId());
    logError(message);
  }
Esempio n. 21
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 private RootContainer initializeRootContainer(EnvironmentConfig envConfig)
     throws ConfigException, InitializationException {
   // Open the database environment
   try {
     RootContainer rc = new RootContainer(this, cfg);
     rc.open(envConfig);
     return rc;
   } catch (DatabaseException e) {
     if (debugEnabled()) {
       TRACER.debugCaught(DebugLogLevel.ERROR, e);
     }
     Message message = ERR_JEB_OPEN_ENV_FAIL.get(e.getMessage());
     throw new InitializationException(message, e);
   }
 }
  public Groundhog getGroundhog(String groundhogName) {

    Groundhog groundhog = null;
    File file = new File(baseDirectoryPath + groundhogName);
    if (file.isDirectory()) {

      try {
        groundhog = new Groundhog(file, defaultCacheSize);
        return groundhog;
      } catch (DatabaseException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
      }
    }
    return groundhog;
  }
Esempio n. 23
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  // Close the environment
  public boolean close() {
    if (m_env != null) {
      try {
        //            	StatsConfig config = new StatsConfig();
        //            	config.setClear(true);
        //            	System.err.println(m_env.getStats(config));

        // Finally, close the environment.
        m_env.close();
      } catch (DatabaseException dbe) {
        System.err.println("Error closing MyDbEnv: " + dbe.toString());
        return false;
      }
    }
    return true;
  }
Esempio n. 24
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  public void close() {

    if (myEnv != null) {
      try {
        Iterator<Entry<String, Database>> it = myDbHashHandle.entrySet().iterator();
        while (it.hasNext()) {
          Database thisDb = it.next().getValue();
          if (thisDb != null) {
            thisDb.close();
          }
        }
        myEnv.close();
      } catch (DatabaseException dbe) {
        System.err.println("Error closing Envorionment" + dbe.toString());
      }
    }
  }
  /** Main */
  public static void main(String argv[]) {

    if (argv.length < 2) {
      usage();
      return;
    }
    File envHomeDirectory = new File(argv[0]);

    boolean doInsertArg = false;
    if (argv[1].equalsIgnoreCase("insert")) {
      doInsertArg = true;
    } else if (argv[1].equalsIgnoreCase("retrieve")) {
      doInsertArg = false;
    } else {
      usage();
    }

    int startOffset = 0;
    int numRecordsVal = 0;

    if (doInsertArg) {

      if (argv.length > 2) {
        numRecordsVal = Integer.parseInt(argv[2]);
      } else {
        usage();
        return;
      }

      if (argv.length > 3) {
        startOffset = Integer.parseInt(argv[3]);
      }
    }

    try {
      BindingExample app =
          new BindingExample(numRecordsVal, doInsertArg, envHomeDirectory, startOffset);
      app.run();
    } catch (DatabaseException e) {
      e.printStackTrace();
      System.exit(EXIT_FAILURE);
    }
    System.exit(EXIT_SUCCESS);
  }
  /**
   * Tests that an exception is thrown when a log header is read with a newer version than the
   * current version. The maxversion.jdb log file is loaded as a resource by this test and written
   * as a regular log file. When the environment is opened, we expect a LogException.
   */
  public void testGreaterVersionNotAllowed() throws DatabaseException, IOException {

    TestUtils.loadLog(getClass(), Utils.MAX_VERSION_NAME, envHome);

    EnvironmentConfig envConfig = TestUtils.initEnvConfig();
    envConfig.setAllowCreate(false);
    envConfig.setTransactional(true);

    try {
      Environment env = new Environment(envHome, envConfig);
      try {
        env.close();
      } catch (Exception ignore) {
      }
    } catch (DatabaseException e) {
      if (e.getCause() instanceof LogException) {
        /* Got LogException as expected. */
        return;
      }
    }
    fail("Expected LogException");
  }
Esempio n. 27
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  /**
   * Creates a customized DirectoryException from the DatabaseException thrown by JE backend.
   *
   * @param e The DatabaseException to be converted.
   * @return DirectoryException created from exception.
   */
  DirectoryException createDirectoryException(DatabaseException e) {
    ResultCode resultCode = DirectoryServer.getServerErrorResultCode();
    Message message;
    if ((e instanceof EnvironmentFailureException) && !rootContainer.isValid()) {
      message = NOTE_BACKEND_ENVIRONMENT_UNUSABLE.get(getBackendID());
      logError(message);
      DirectoryServer.sendAlertNotification(
          DirectoryServer.getInstance(), ALERT_TYPE_BACKEND_ENVIRONMENT_UNUSABLE, message);
    }

    String jeMessage = e.getMessage();
    if (jeMessage == null) {
      jeMessage = stackTraceToSingleLineString(e);
    }
    message = ERR_JEB_DATABASE_EXCEPTION.get(jeMessage);
    return new DirectoryException(resultCode, message, e);
  }
  private void doClose(boolean doCheckpoint) throws DatabaseException {

    StringBuffer errors = new StringBuffer();

    try {
      // refined trace Tracer.trace(Level.FINE, this, "Close of
      // environment " + envHome + " started");

      try {
        envState.checkState(DbEnvState.VALID_FOR_CLOSE, DbEnvState.CLOSED);
      } catch (DatabaseException DBE) {
        throw DBE;
      }

      /*
       * Begin shutdown of the deamons before checkpointing. Cleaning
       * during the checkpoint is wasted and slows down the checkpoint.
       */
      requestShutdownDaemons();

      /* Checkpoint to bound recovery time. */
      if (doCheckpoint
          && !isReadOnly
          && (envState != DbEnvState.INVALID)
          && logManager.getLastLsnAtRecovery() != fileManager.getLastUsedLsn()) {

        /*
         * Force a checkpoint. Don't allow deltas (minimize recovery
         * time) because they cause inefficiencies for two reasons: (1)
         * recovering BINDeltas causes extra random I/O in order to
         * reconstitute BINS, which can greatly increase recovery time,
         * and (2) logging deltas during close causes redundant logging
         * by the full checkpoint after recovery.
         */
        CheckpointConfig ckptConfig = new CheckpointConfig();
        ckptConfig.setForce(true);
        ckptConfig.setMinimizeRecoveryTime(true);
        try {
          invokeCheckpoint(
              ckptConfig,
              false, // flushAll
              "close");
        } catch (DatabaseException IE) {
          errors.append("\nException performing checkpoint: ");
          errors.append(IE.toString()).append("\n");
        }
      }

      try {
        shutdownDaemons();
      } catch (InterruptedException IE) {
        errors.append("\nException shutting down daemon threads: ");
        errors.append(IE.toString()).append("\n");
      }

      /* Flush log. */
      // refined trace Tracer.trace(Level.FINE, this, "Env " + envHome + "
      // daemons shutdown");
      try {
        logManager.flush();
      } catch (DatabaseException DBE) {
        errors.append("\nException flushing log manager: ");
        errors.append(DBE.toString()).append("\n");
      }

      try {
        fileManager.clear();
      } catch (IOException IOE) {
        errors.append("\nException clearing file manager: ");
        errors.append(IOE.toString()).append("\n");
      } catch (DatabaseException DBE) {
        errors.append("\nException clearing file manager: ");
        errors.append(DBE.toString()).append("\n");
      }

      try {
        fileManager.close();
      } catch (IOException IOE) {
        errors.append("\nException clearing file manager: ");
        errors.append(IOE.toString()).append("\n");
      } catch (DatabaseException DBE) {
        errors.append("\nException clearing file manager: ");
        errors.append(DBE.toString()).append("\n");
      }

      try {
        inMemoryINs.clear();
      } catch (DatabaseException DBE) {
        errors.append("\nException closing file manager: ");
        errors.append(DBE.toString()).append("\n");
      }

      hook_afterDoClose(errors);
    } finally {
      envState = DbEnvState.CLOSED;
    }

    if (errors.length() > 0 && savedInvalidatingException == null) {

      /* Don't whine again if we've already whined. */
      throw new RunRecoveryException(this, errors.toString());
    }
  }
Esempio n. 29
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  /** {@inheritDoc} */
  @Override()
  public void initializeBackend() throws ConfigException, InitializationException {
    // Checksum this db environment and register its offline state id/checksum.
    DirectoryServer.registerOfflineBackendStateID(this.getBackendID(), checksumDbEnv());

    if (rootContainer == null) {
      EnvironmentConfig envConfig = ConfigurableEnvironment.parseConfigEntry(cfg);
      rootContainer = initializeRootContainer(envConfig);
    }

    // Preload the database cache.
    rootContainer.preload(cfg.getPreloadTimeLimit());

    try {
      // Log an informational message about the number of entries.
      Message message =
          NOTE_JEB_BACKEND_STARTED.get(cfg.getBackendId(), rootContainer.getEntryCount());
      logError(message);
    } catch (DatabaseException databaseException) {
      if (debugEnabled()) {
        TRACER.debugCaught(DebugLogLevel.ERROR, databaseException);
      }
      Message message = WARN_JEB_GET_ENTRY_COUNT_FAILED.get(databaseException.getMessage());
      throw new InitializationException(message, databaseException);
    }

    for (DN dn : cfg.getBaseDN()) {
      try {
        DirectoryServer.registerBaseDN(dn, this, false);
      } catch (Exception e) {
        if (debugEnabled()) {
          TRACER.debugCaught(DebugLogLevel.ERROR, e);
        }

        Message message =
            ERR_BACKEND_CANNOT_REGISTER_BASEDN.get(String.valueOf(dn), String.valueOf(e));
        throw new InitializationException(message, e);
      }
    }

    // Register a monitor provider for the environment.
    rootContainerMonitor = rootContainer.getMonitorProvider();
    DirectoryServer.registerMonitorProvider(rootContainerMonitor);

    // Register as disk space monitor handler
    File parentDirectory = getFileForPath(cfg.getDBDirectory());
    File backendDirectory = new File(parentDirectory, cfg.getBackendId());
    diskMonitor =
        new DiskSpaceMonitor(
            getBackendID() + " backend",
            backendDirectory,
            cfg.getDiskLowThreshold(),
            cfg.getDiskFullThreshold(),
            5,
            TimeUnit.SECONDS,
            this);
    diskMonitor.initializeMonitorProvider(null);
    DirectoryServer.registerMonitorProvider(diskMonitor);

    // Register as an AlertGenerator.
    DirectoryServer.registerAlertGenerator(this);
    // Register this backend as a change listener.
    cfg.addLocalDBChangeListener(this);
  }