Java EditLogFileInputStream类代码示例

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
@Test
public void testGetInputStreamNoValidationNoCheckLastTxId() throws Exception {
  setupTest("test-get-input-stream-no-validation-no-check-last-txid");
  File tempEditsFile = FSEditLogTestUtil.createTempEditsFile(
      "test-get-input-stream-with-validation");
  try {
    EditLogOutputStream bkeos = bkjm.startLogSegment(1);
    EditLogOutputStream elfos =
        new EditLogFileOutputStream(tempEditsFile, null);
    elfos.create();
    FSEditLogTestUtil.populateStreams(1, 100, bkeos, elfos);
    EditLogInputStream bkeis =
        getJournalInputStreamDontCheckLastTxId(bkjm, 1);
    EditLogInputStream elfis = new EditLogFileInputStream(tempEditsFile);
    Map<String, EditLogInputStream> streamByName =
        ImmutableMap.of("BookKeeper", bkeis, "File", elfis);
    FSEditLogTestUtil.assertStreamsAreEquivalent(100, streamByName);
  } finally {
    if (!tempEditsFile.delete()) {
      LOG.warn("Unable to delete edits file: " +
          tempEditsFile.getAbsolutePath());
    }
  }
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
@Override
public void selectInputStreams(Collection<EditLogInputStream> streams,
    long fromTxnId, boolean inProgressOk) throws IOException {

  QuorumCall<AsyncLogger, RemoteEditLogManifest> q =
      loggers.getEditLogManifest(fromTxnId, inProgressOk);
  Map<AsyncLogger, RemoteEditLogManifest> resps =
      loggers.waitForWriteQuorum(q, selectInputStreamsTimeoutMs,
          "selectInputStreams");
  
  LOG.debug("selectInputStream manifests:\n" +
      Joiner.on("\n").withKeyValueSeparator(": ").join(resps));
  
  final PriorityQueue<EditLogInputStream> allStreams = 
      new PriorityQueue<EditLogInputStream>(64,
          JournalSet.EDIT_LOG_INPUT_STREAM_COMPARATOR);
  for (Map.Entry<AsyncLogger, RemoteEditLogManifest> e : resps.entrySet()) {
    AsyncLogger logger = e.getKey();
    RemoteEditLogManifest manifest = e.getValue();
    
    for (RemoteEditLog remoteLog : manifest.getLogs()) {
      URL url = logger.buildURLToFetchLogs(remoteLog.getStartTxId());

      EditLogInputStream elis = EditLogFileInputStream.fromUrl(
          connectionFactory, url, remoteLog.getStartTxId(),
          remoteLog.getEndTxId(), remoteLog.isInProgress());
      allStreams.add(elis);
    }
  }
  JournalSet.chainAndMakeRedundantStreams(streams, allStreams, fromTxnId);
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
private long verifyEditLogs(FSNamesystem namesystem, FSImage fsimage, 
                            String logFileName, long startTxId)
  throws IOException {
  
  long numEdits = -1;
  
  // Verify that we can read in all the transactions that we have written.
  // If there were any corruptions, it is likely that the reading in
  // of these transactions will throw an exception.
  for (StorageDirectory sd :
    fsimage.storage.dirIterable(NameNodeDirType.EDITS)) {

    File editFile = new File(sd.getCurrentDir(), logFileName);
      
    System.out.println("Verifying file: " + editFile);
    FSEditLogLoader loader = new FSEditLogLoader(namesystem);
    int numEditsThisLog = loader.loadFSEdits(new EditLogFileInputStream(editFile), 
        startTxId -1);
    
    System.out.println("Number of edits: " + numEditsThisLog);
    LOG.info("num edits: " + numEdits + " this log: " + numEditsThisLog);
    assertTrue(numEdits == -1 || numEditsThisLog == numEdits);
    numEdits = numEditsThisLog;
  }

  assertTrue(numEdits != -1);
  return numEdits;
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
public EditLogByteInputStream(byte[] data) throws IOException {
  len = data.length;
  input = new ByteArrayInputStream(data);

  BufferedInputStream bin = new BufferedInputStream(input);
  DataInputStream in = new DataInputStream(bin);      
  tracker = new FSEditLogLoader.PositionTrackingInputStream(in);
  in = new DataInputStream(tracker);  
  version = EditLogFileInputStream.readLogVersion(in);           
  reader = new FSEditLogOp.Reader(in, version);
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
private void testReadFromClosedLedgerAfterWriteInner(int numEdits)
  throws Exception {
  LedgerHandle ledgerOut = createLedger();
  long ledgerId = ledgerOut.getId();
  BookKeeperEditLogOutputStream bkEditsOut =
      new BookKeeperEditLogOutputStream(ledgerOut);
  EditLogFileOutputStream fileEditsOut =
      new EditLogFileOutputStream(tempEditsFile, null);

  FSEditLogTestUtil.createAndPopulateStreams(1,
      numEdits, bkEditsOut, fileEditsOut);

  BookKeeperEditLogInputStream bkEditsIn =
      new BookKeeperEditLogInputStream(ledgerProvider,
          ledgerId,
          0,
          1,
          numEdits,
          false);
  EditLogFileInputStream fileEditsIn =
      new EditLogFileInputStream(tempEditsFile);

  assertEquals("Length in bytes must be equal!",
      bkEditsIn.length(), fileEditsIn.length());

  FSEditLogTestUtil.assertStreamsAreEquivalent(numEdits,
      ImmutableMap.of("BookKeeper", bkEditsIn, "File", fileEditsIn));
  assertNull("BookKeeper edit log must end at txid 100", bkEditsIn.readOp());
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
@Test
public void testGetInputStreamWithValidation() throws Exception {
  setupTest("test-get-input-stream-with-validation");
  File tempEditsFile = FSEditLogTestUtil.createTempEditsFile(
      "test-get-input-stream-with-validation");
  try {
    TestBKJMInjectionHandler h = new TestBKJMInjectionHandler();
    InjectionHandler.set(h);
    EditLogOutputStream bkeos = bkjm.startLogSegment(1);
    EditLogOutputStream elfos =
        new EditLogFileOutputStream(tempEditsFile, null);
    elfos.create();
    FSEditLogTestUtil.populateStreams(1, 100, bkeos, elfos);
    EditLogInputStream bkeis =
        FSEditLogTestUtil.getJournalInputStream(bkjm, 1, true);
    EditLogInputStream elfis = new EditLogFileInputStream(tempEditsFile);
    Map<String, EditLogInputStream> streamByName =
        ImmutableMap.of("BookKeeper", bkeis, "File", elfis);
    FSEditLogTestUtil.assertStreamsAreEquivalent(100, streamByName);
    assertNotNull("Log was validated", h.logValidation);
    assertEquals("numTrasactions validated correctly",
        100, h.logValidation.getNumTransactions());
    assertEquals("endTxId validated correctly",
        100, h.logValidation.getEndTxId());
  } finally {
    if (!tempEditsFile.delete()) {
      LOG.warn("Unable to delete edits file: " +
          tempEditsFile.getAbsolutePath());
    }
  }
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
@Override
public void selectInputStreams(Collection<EditLogInputStream> streams,
    long fromTxnId, boolean inProgressOk, boolean forReading) throws IOException {

  QuorumCall<AsyncLogger, RemoteEditLogManifest> q =
      loggers.getEditLogManifest(fromTxnId, forReading);
  Map<AsyncLogger, RemoteEditLogManifest> resps =
      loggers.waitForWriteQuorum(q, selectInputStreamsTimeoutMs,
          "selectInputStreams");
  
  LOG.debug("selectInputStream manifests:\n" +
      Joiner.on("\n").withKeyValueSeparator(": ").join(resps));
  
  final PriorityQueue<EditLogInputStream> allStreams = 
      new PriorityQueue<EditLogInputStream>(64,
          JournalSet.EDIT_LOG_INPUT_STREAM_COMPARATOR);
  for (Map.Entry<AsyncLogger, RemoteEditLogManifest> e : resps.entrySet()) {
    AsyncLogger logger = e.getKey();
    RemoteEditLogManifest manifest = e.getValue();
    
    for (RemoteEditLog remoteLog : manifest.getLogs()) {
      URL url = logger.buildURLToFetchLogs(remoteLog.getStartTxId());

      EditLogInputStream elis = EditLogFileInputStream.fromUrl(
          url, remoteLog.getStartTxId(), remoteLog.getEndTxId(),
          remoteLog.isInProgress());
      allStreams.add(elis);
    }
  }
  JournalSet.chainAndMakeRedundantStreams(
      streams, allStreams, fromTxnId, inProgressOk);
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
@Override
public void selectInputStreams(Collection<EditLogInputStream> streams,
    long fromTxnId, boolean inProgressOk, boolean forReading) throws IOException {

  QuorumCall<AsyncLogger, RemoteEditLogManifest> q =
      loggers.getEditLogManifest(fromTxnId, forReading, inProgressOk);
  Map<AsyncLogger, RemoteEditLogManifest> resps =
      loggers.waitForWriteQuorum(q, selectInputStreamsTimeoutMs,
          "selectInputStreams");
  
  LOG.debug("selectInputStream manifests:\n" +
      Joiner.on("\n").withKeyValueSeparator(": ").join(resps));
  
  final PriorityQueue<EditLogInputStream> allStreams = 
      new PriorityQueue<EditLogInputStream>(64,
          JournalSet.EDIT_LOG_INPUT_STREAM_COMPARATOR);
  for (Map.Entry<AsyncLogger, RemoteEditLogManifest> e : resps.entrySet()) {
    AsyncLogger logger = e.getKey();
    RemoteEditLogManifest manifest = e.getValue();
    
    for (RemoteEditLog remoteLog : manifest.getLogs()) {
      URL url = logger.buildURLToFetchLogs(remoteLog.getStartTxId());

      EditLogInputStream elis = EditLogFileInputStream.fromUrl(
          url, remoteLog.getStartTxId(), remoteLog.getEndTxId(),
          remoteLog.isInProgress());
      allStreams.add(elis);
    }
  }
  JournalSet.chainAndMakeRedundantStreams(streams, allStreams, fromTxnId);
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
private void verifyEditLogs(FSNamesystem namesystem, FSImage fsimage)
  throws IOException {
  // Verify that we can read in all the transactions that we have written.
  // If there were any corruptions, it is likely that the reading in
  // of these transactions will throw an exception.
  for (Iterator<StorageDirectory> it = 
         fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
    File editFile = FSImage.getImageFile(it.next(), NameNodeFile.EDITS);
    System.out.println("Verifying file: " + editFile);
    int numEdits = new FSEditLogLoader(namesystem).loadFSEdits(
      new EditLogFileInputStream(editFile));
    System.out.println("Number of edits: " + numEdits);
  }
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
@Test
public void testPreserveEditLogs() throws Exception {
  conf = new HdfsConfiguration();
  conf = UpgradeUtilities.initializeStorageStateConf(1, conf);
  String[] nameNodeDirs = conf.getStrings(DFSConfigKeys.DFS_NAMENODE_NAME_DIR_KEY);
  conf.setBoolean(DFSConfigKeys.DFS_DATANODE_DUPLICATE_REPLICA_DELETION, false);

  log("Normal NameNode upgrade", 1);
  File[] created =
      UpgradeUtilities.createNameNodeStorageDirs(nameNodeDirs, "current");
  for (final File createdDir : created) {
    List<String> fileNameList =
        IOUtils.listDirectory(createdDir, EditLogsFilter.INSTANCE);
    for (String fileName : fileNameList) {
      String tmpFileName = fileName + ".tmp";
      File existingFile = new File(createdDir, fileName);
      File tmpFile = new File(createdDir, tmpFileName);
      Files.move(existingFile.toPath(), tmpFile.toPath());
      File newFile = new File(createdDir, fileName);
      Preconditions.checkState(newFile.createNewFile(),
          "Cannot create new edits log file in " + createdDir);
      EditLogFileInputStream in = new EditLogFileInputStream(tmpFile,
          HdfsConstants.INVALID_TXID, HdfsConstants.INVALID_TXID,
          false);
      EditLogFileOutputStream out = new EditLogFileOutputStream(conf, newFile,
          (int)tmpFile.length());
      out.create(NameNodeLayoutVersion.CURRENT_LAYOUT_VERSION + 1);
      FSEditLogOp logOp = in.readOp();
      while (logOp != null) {
        out.write(logOp);
        logOp = in.readOp();
      }
      out.setReadyToFlush();
      out.flushAndSync(true);
      out.close();
      Files.delete(tmpFile.toPath());
    }
  }

  cluster = createCluster();

  DFSInotifyEventInputStream ieis =
      cluster.getFileSystem().getInotifyEventStream(0);
  EventBatch batch = ieis.poll();
  Event[] events = batch.getEvents();
  assertTrue("Should be able to get transactions before the upgrade.",
      events.length > 0);
  assertEquals(events[0].getEventType(), Event.EventType.CREATE);
  assertEquals(((CreateEvent) events[0]).getPath(), "/TestUpgrade");
  cluster.shutdown();
  UpgradeUtilities.createEmptyDirs(nameNodeDirs);
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
private void testReadAndRefreshAfterEachTransactionInner(int numEdits)
  throws Exception {
  FSEditLog.sizeFlushBuffer = 100;
  LedgerHandle ledgerOut = createLedger();
  long ledgerId = ledgerOut.getId();
  BookKeeperEditLogOutputStream bkEditsOut =
      new BookKeeperEditLogOutputStream(ledgerOut);
  EditLogFileOutputStream fileEditsOut =
      new EditLogFileOutputStream(tempEditsFile, null);

  FSEditLogTestUtil.createAndPopulateStreams(1,
      numEdits, bkEditsOut, fileEditsOut);

  BookKeeperEditLogInputStream bkEditsIn =
      new BookKeeperEditLogInputStream(ledgerProvider,
          ledgerId,
          0,
          1,
          numEdits,
          false);

  EditLogFileInputStream fileEditsIn =
      new EditLogFileInputStream(tempEditsFile);

  assertEquals("Length in bytes must be equal!",
      bkEditsIn.length(), fileEditsIn.length());

  long lastBkPos = bkEditsIn.getPosition();
  long lastFilePos = fileEditsIn.getPosition();
  for (int i = 1; i <= numEdits; i++) {
    assertEquals("Position in file must be equal position in bk",
        lastBkPos, lastFilePos);
    bkEditsIn.refresh(lastBkPos, -1);
    fileEditsIn.refresh(lastFilePos, -1);
    FSEditLogOp opFromBk = bkEditsIn.readOp();
    FSEditLogOp opFromFile = fileEditsIn.readOp();
    if (LOG.isDebugEnabled()) {
      LOG.debug("txId = " + i + ", " + "opFromBk = " + opFromBk +
          ", opFromFile = " + opFromFile);
    }
    assertEquals(
        "Operation read from file and BookKeeper must be same after refresh",
        opFromBk, opFromFile);
    lastBkPos = bkEditsIn.getPosition();
    lastFilePos = fileEditsIn.getPosition();
  }
  assertNull("BookKeeper edit log must end at last txId", bkEditsIn.readOp());
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
private void testReadBufferGreaterThanLedgerSizeInner(int numEdits)
    throws Exception {
  LedgerHandle ledgerOut = createLedger();
  long ledgerId = ledgerOut.getId();
  BookKeeperEditLogInputStream bkEditsIn =
      new BookKeeperEditLogInputStream(ledgerProvider,
          ledgerId,
          0,
          1,
          -1,
          true);
  EditLogFileOutputStream fileEditsOut =
      new EditLogFileOutputStream(tempEditsFile, null);
  bkEditsIn.init();
  // Set the edit log buffer flush size smaller than the size of
  // of the buffer in BufferedInputStream in BookKeeperJournalInputStream
  FSEditLog.sizeFlushBuffer = bkEditsIn.bin.available() / 3;
  LOG.info("Set flush buffer size to " + FSEditLog.sizeFlushBuffer);

  BookKeeperEditLogOutputStream bkEditsOut =
      new BookKeeperEditLogOutputStream(ledgerOut);

  FSEditLogTestUtil.createAndPopulateStreams(1, numEdits, bkEditsOut,
      fileEditsOut);

  // Re-try refreshing up to ten times until we are able to refresh
  // successfully to be beginning of the ledger and read the edit log
  // layout version
  int maxTries = 10;
  for (int i = 0; i < maxTries; i++) {
    try {
      bkEditsIn.refresh(0, -1);
      assertEquals("refresh succeeded", bkEditsIn.logVersion,
          FSConstants.LAYOUT_VERSION);
    } catch (AssertionFailedError e) {
      if (i == maxTries) {
        // Fail the unit test rethrowing the assertion failure if we've
        // reached the maximum number of retries
        throw e;
      }
    }
  }
  EditLogFileInputStream fileEditsIn =
      new EditLogFileInputStream(tempEditsFile);
  for (int i = 0; i <= numEdits; i++) {
    FSEditLogOp opFromBk = bkEditsIn.readOp();
    FSEditLogOp opFromFile = fileEditsIn.readOp();
    if (LOG.isDebugEnabled()) {
      LOG.debug("txId = " + i + ", " + "opFromBk = " + opFromBk +
          ", opFromFile = " + opFromFile);
    }
    assertEquals(
        "Operation read from file and BookKeeper must be same after refresh",
        opFromBk, opFromFile);
  }
  assertNull("BookKeeper edit log must end at txid 1000", bkEditsIn.readOp());
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
/**
 * Merge Journal Spool to memory.<p>
 * Journal Spool reader reads journal records from edits.new.
 * When it reaches the end of the file it sets {@link JSpoolState} to WAIT.
 * This blocks journaling (see {@link #journal(int,byte[])}.
 * The reader
 * <ul>
 * <li> reads remaining journal records if any,</li>
 * <li> renames edits.new to edits,</li>
 * <li> sets {@link JSpoolState} to OFF,</li> 
 * <li> and notifies the journaling thread.</li>
 * </ul>
 * Journaling resumes with applying new journal records to the memory state,
 * and writing them into edits file(s).
 */
void convergeJournalSpool() throws IOException {
  Iterator<StorageDirectory> itEdits = dirIterator(NameNodeDirType.EDITS);
  if(! itEdits.hasNext())
    throw new IOException("Could not locate checkpoint directories");
  StorageDirectory sdEdits = itEdits.next();
  int numEdits = 0;
  File jSpoolFile = getJSpoolFile(sdEdits);
  long startTime = now();
  if(jSpoolFile.exists()) {
    // load edits.new
    EditLogFileInputStream edits = new EditLogFileInputStream(jSpoolFile);
    DataInputStream in = edits.getDataInputStream();
    FSEditLogLoader logLoader = new FSEditLogLoader(namesystem);
    numEdits += logLoader.loadFSEdits(in, false);

    // first time reached the end of spool
    jsState = JSpoolState.WAIT;
    numEdits += logLoader.loadEditRecords(getLayoutVersion(), in, true);
    getFSNamesystem().dir.updateCountForINodeWithQuota();
    edits.close();
  }

  FSImage.LOG.info("Edits file " + jSpoolFile.getCanonicalPath() 
      + " of size " + jSpoolFile.length() + " edits # " + numEdits 
      + " loaded in " + (now()-startTime)/1000 + " seconds.");

  // rename spool edits.new to edits making it in sync with the active node
  // subsequent journal records will go directly to edits
  editLog.revertFileStreams(STORAGE_JSPOOL_DIR + "/" + STORAGE_JSPOOL_FILE);

  // write version file
  resetVersion(false, imageDigest);

  // wake up journal writer
  synchronized(this) {
    jsState = JSpoolState.OFF;
    notifyAll();
  }

  // Rename lastcheckpoint.tmp to previous.checkpoint
  for(StorageDirectory sd : storageDirs) {
    moveLastCheckpoint(sd);
  }
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
/**
 * Tests transaction logging in dfs.
 */
public void testEditLog() throws IOException {

  // start a cluster 
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = null;
  FileSystem fileSys = null;

  try {
    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(NUM_DATA_NODES).build();
    cluster.waitActive();
    fileSys = cluster.getFileSystem();
    final FSNamesystem namesystem = cluster.getNamesystem();

    for (Iterator<URI> it = cluster.getNameDirs().iterator(); it.hasNext(); ) {
      File dir = new File(it.next().getPath());
      System.out.println(dir);
    }
    
    FSImage fsimage = namesystem.getFSImage();
    FSEditLog editLog = fsimage.getEditLog();

    // set small size of flush buffer
    editLog.setBufferCapacity(2048);
    editLog.close();
    editLog.open();
    namesystem.getDelegationTokenSecretManager().startThreads();
  
    // Create threads and make them run transactions concurrently.
    Thread threadId[] = new Thread[NUM_THREADS];
    for (int i = 0; i < NUM_THREADS; i++) {
      Transactions trans = new Transactions(namesystem, NUM_TRANSACTIONS);
      threadId[i] = new Thread(trans, "TransactionThread-" + i);
      threadId[i].start();
    }

    // wait for all transactions to get over
    for (int i = 0; i < NUM_THREADS; i++) {
      try {
        threadId[i].join();
      } catch (InterruptedException e) {
        i--;      // retry 
      }
    } 
    
    editLog.close();

    // Verify that we can read in all the transactions that we have written.
    // If there were any corruptions, it is likely that the reading in
    // of these transactions will throw an exception.
    //
    FSEditLogLoader loader = new FSEditLogLoader(namesystem);
    namesystem.getDelegationTokenSecretManager().stopThreads();
    int numKeys = namesystem.getDelegationTokenSecretManager().getNumberOfKeys();
    for (Iterator<StorageDirectory> it = 
            fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
      File editFile = FSImage.getImageFile(it.next(), NameNodeFile.EDITS);
      System.out.println("Verifying file: " + editFile);
      int numEdits = loader.loadFSEdits(
                                new EditLogFileInputStream(editFile));
      assertTrue("Verification for " + editFile + " failed. " +
                 "Expected " + (NUM_THREADS * opsPerTrans * NUM_TRANSACTIONS + numKeys) + " transactions. "+
                 "Found " + numEdits + " transactions.",
                 numEdits == NUM_THREADS * opsPerTrans * NUM_TRANSACTIONS +numKeys);

    }
  } finally {
    if(fileSys != null) fileSys.close();
    if(cluster != null) cluster.shutdown();
  }
}
 

import org.apache.hadoop.hdfs.server.namenode.EditLogFileInputStream; //导入依赖的package包/类
/**
 * Test edit log with different initial buffer size
 * 
 * @param initialSize initial edit log buffer size
 * @throws IOException
 */
private void testEditLog(int initialSize) throws IOException {

  // start a cluster 
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = null;
  FileSystem fileSys = null;

  try {
    cluster = new MiniDFSCluster.Builder(conf).numDataNodes(NUM_DATA_NODES).build();
    cluster.waitActive();
    fileSys = cluster.getFileSystem();
    final FSNamesystem namesystem = cluster.getNamesystem();

    for (Iterator<URI> it = cluster.getNameDirs().iterator(); it.hasNext(); ) {
      File dir = new File(it.next().getPath());
      System.out.println(dir);
    }

    FSImage fsimage = namesystem.getFSImage();
    FSEditLog editLog = fsimage.getEditLog();

    // set small size of flush buffer
    editLog.setBufferCapacity(initialSize);
    editLog.close();
    editLog.open();
  
    // Create threads and make them run transactions concurrently.
    Thread threadId[] = new Thread[NUM_THREADS];
    for (int i = 0; i < NUM_THREADS; i++) {
      Transactions trans = new Transactions(namesystem, NUM_TRANSACTIONS);
      threadId[i] = new Thread(trans, "TransactionThread-" + i);
      threadId[i].start();
    }

    // wait for all transactions to get over
    for (int i = 0; i < NUM_THREADS; i++) {
      try {
        threadId[i].join();
      } catch (InterruptedException e) {
        i--;      // retry 
      }
    } 
    
    editLog.close();
    editLog.open();

    // Verify that we can read in all the transactions that we have written.
    // If there were any corruptions, it is likely that the reading in
    // of these transactions will throw an exception.
    //
    FSEditLogLoader loader = new FSEditLogLoader(namesystem);
    for (Iterator<StorageDirectory> it = 
            fsimage.dirIterator(NameNodeDirType.EDITS); it.hasNext();) {
      File editFile = FSImage.getImageFile(it.next(), NameNodeFile.EDITS);
      System.out.println("Verifying file: " + editFile);
      int numEdits = loader.loadFSEdits(
                                new EditLogFileInputStream(editFile));
      int numLeases = namesystem.leaseManager.countLease();
      System.out.println("Number of outstanding leases " + numLeases);
      assertEquals(0, numLeases);
      assertTrue("Verification for " + editFile + " failed. " +
                 "Expected " + (NUM_THREADS * 2 * NUM_TRANSACTIONS) + " transactions. "+
                 "Found " + numEdits + " transactions.",
                 numEdits == NUM_THREADS * 2 * NUM_TRANSACTIONS);

    }
  } finally {
    if(fileSys != null) fileSys.close();
    if(cluster != null) cluster.shutdown();
  }
}