Java 类org.apache.hadoop.hdfs.protocol.AlreadyBeingCreatedException 实例源码

/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    if (fs.exists(idPath)) {
      // try appending to it so that it will fail fast if another balancer is
      // running.
      IOUtils.closeStream(fs.append(idPath));
      fs.delete(idPath, true);
    }
    final FSDataOutputStream fsout = fs.create(idPath, false);
    // mark balancer idPath to be deleted during filesystem closure
    fs.deleteOnExit(idPath);
    if (write2IdFile) {
      fsout.writeBytes(InetAddress.getLocalHost().getHostName());
      fsout.hflush();
    }
    return fsout;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

@Override
public FSDataOutputStream call() throws IOException {
  try {
    FileSystem fs = FSUtils.getCurrentFileSystem(getConf());
    FsPermission defaultPerms = FSUtils.getFilePermissions(fs, getConf(),
        HConstants.DATA_FILE_UMASK_KEY);
    Path tmpDir = new Path(FSUtils.getRootDir(getConf()), HConstants.HBASE_TEMP_DIRECTORY);
    fs.mkdirs(tmpDir);
    HBCK_LOCK_PATH = new Path(tmpDir, HBCK_LOCK_FILE);
    final FSDataOutputStream out = createFileWithRetries(fs, HBCK_LOCK_PATH, defaultPerms);
    out.writeBytes(InetAddress.getLocalHost().toString());
    out.flush();
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    if (fs.exists(idPath)) {
      // try appending to it so that it will fail fast if another balancer is
      // running.
      IOUtils.closeStream(fs.append(idPath));
      fs.delete(idPath, true);
    }
    final FSDataOutputStream fsout = fs.create(idPath, false);
    // mark balancer idPath to be deleted during filesystem closure
    fs.deleteOnExit(idPath);
    if (write2IdFile) {
      fsout.writeBytes(InetAddress.getLocalHost().getHostName());
      fsout.hflush();
    }
    return fsout;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    if (fs.exists(idPath)) {
      // try appending to it so that it will fail fast if another balancer is
      // running.
      IOUtils.closeStream(fs.append(idPath));
      fs.delete(idPath, true);
    }
    final FSDataOutputStream fsout = fs.create(idPath, false);
    // mark balancer idPath to be deleted during filesystem closure
    fs.deleteOnExit(idPath);
    if (write2IdFile) {
      fsout.writeBytes(InetAddress.getLocalHost().getHostName());
      fsout.hflush();
    }
    return fsout;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag, boolean createParent,
    short replication, long blockSize, CryptoProtocolVersion[] supportedVersions)
    throws AccessControlException, AlreadyBeingCreatedException,
           DSQuotaExceededException, FileAlreadyExistsException,
           FileNotFoundException, NSQuotaExceededException,
           ParentNotDirectoryException, SafeModeException,
           UnresolvedLinkException, SnapshotAccessControlException,
           IOException {
  try {
    AuthorizationProvider.beginClientOp();
    return server.create(src, masked, clientName, flag, createParent,
        replication, blockSize, supportedVersions);
  } finally {
    AuthorizationProvider.endClientOp();
  }
}

/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    final FSDataOutputStream out = fs.create(idPath);
    if (write2IdFile) {
      out.writeBytes(InetAddress.getLocalHost().getHostName());
      out.hflush();
    }
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

static ClientProtocol createNamenode(ClientProtocol rpcNamenode,
    Configuration conf)
  throws IOException {
  long sleepTime = conf.getLong("dfs.client.rpc.retry.sleep",
      LEASE_SOFTLIMIT_PERIOD);
  RetryPolicy createPolicy = RetryPolicies.retryUpToMaximumCountWithFixedSleep(
      5, sleepTime, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>,RetryPolicy> remoteExceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class, createPolicy);

  Map<Class<? extends Exception>,RetryPolicy> exceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class,
      RetryPolicies.retryByRemoteException(
          RetryPolicies.TRY_ONCE_THEN_FAIL, remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String,RetryPolicy> methodNameToPolicyMap = new HashMap<String,RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (ClientProtocol) RetryProxy.create(ClientProtocol.class,
      rpcNamenode, methodNameToPolicyMap);
}

/** Create a {@link NameNode} proxy */
static DatanodeProtocolPB createNamenodeWithRetry(
    DatanodeProtocolPB rpcNamenode) {
  RetryPolicy createPolicy = RetryPolicies
      .retryUpToMaximumCountWithFixedSleep(5,
          HdfsConstants.LEASE_SOFTLIMIT_PERIOD, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>, RetryPolicy> remoteExceptionToPolicyMap = 
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class,
      createPolicy);

  Map<Class<? extends Exception>, RetryPolicy> exceptionToPolicyMap =
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class, RetryPolicies
      .retryByRemoteException(RetryPolicies.TRY_ONCE_THEN_FAIL,
          remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String, RetryPolicy> methodNameToPolicyMap = new HashMap<String, RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (DatanodeProtocolPB) RetryProxy.create(DatanodeProtocolPB.class,
      rpcNamenode, methodNameToPolicyMap);
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto req = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize)
      .build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

/**
 * The idea for making sure that there is no more than one instance
 * running in an HDFS is to create a file in the HDFS, writes the hostname
 * of the machine on which the instance is running to the file, but did not
 * close the file until it exits. 
 * 
 * This prevents the second instance from running because it can not
 * creates the file while the first one is running.
 * 
 * This method checks if there is any running instance. If no, mark yes.
 * Note that this is an atomic operation.
 * 
 * @return null if there is a running instance;
 *         otherwise, the output stream to the newly created file.
 */
private OutputStream checkAndMarkRunning() throws IOException {
  try {
    final FSDataOutputStream out = fs.create(idPath);
    if (write2IdFile) {
      out.writeBytes(InetAddress.getLocalHost().getHostName());
      out.hflush();
    }
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

public void create(final String src, final FsPermission masked,
    final String clientName, final EnumSetWritable<CreateFlag> flag,
    final boolean createParent, final short replication, final long blockSize)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  ClientActionHandler handler = new ClientActionHandler() {
    @Override
    public Object doAction(ClientProtocol namenode)
        throws RemoteException, IOException {
      namenode
          .create(src, masked, clientName, flag, createParent, replication,
              blockSize);
      return null;
    }
  };
  doClientActionWithRetry(handler, "create");
}

public void create(final String src, final FsPermission masked,
    final String clientName, final EnumSetWritable<CreateFlag> flag,
    final boolean createParent, final short replication, final long blockSize,
    final EncodingPolicy policy)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  ClientActionHandler handler = new ClientActionHandler() {
    @Override
    public Object doAction(ClientProtocol namenode)
        throws RemoteException, IOException {
      namenode
          .create(src, masked, clientName, flag, createParent, replication,
              blockSize, policy);
      return null;
    }
  };
  doClientActionWithRetry(handler, "create");
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag, boolean createParent,
    short replication, long blockSize, EncodingPolicy policy)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto.Builder builder =
      CreateRequestProto.newBuilder().setSrc(src)
          .setMasked(PBHelper.convert(masked)).setClientName(clientName)
          .setCreateFlag(PBHelper.convertCreateFlag(flag))
          .setCreateParent(createParent).setReplication(replication)
          .setBlockSize(blockSize);
  if (policy != null) {
    builder.setPolicy(PBHelper.convert(policy));
  }
  CreateRequestProto req = builder.build();
  try {
    CreateResponseProto result = rpcProxy.create(null, req);
    return result.hasFs() ? PBHelper.convert(result.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }
}

@Override
public FSDataOutputStream call() throws IOException {
  try {
    FileSystem fs = FSUtils.getCurrentFileSystem(getConf());
    FsPermission defaultPerms = FSUtils.getFilePermissions(fs, getConf(),
        HConstants.DATA_FILE_UMASK_KEY);
    Path tmpDir = new Path(FSUtils.getRootDir(getConf()), HConstants.HBASE_TEMP_DIRECTORY);
    fs.mkdirs(tmpDir);
    HBCK_LOCK_PATH = new Path(tmpDir, HBCK_LOCK_FILE);
    final FSDataOutputStream out = createFileWithRetries(fs, HBCK_LOCK_PATH, defaultPerms);
    out.writeBytes(InetAddress.getLocalHost().toString());
    out.flush();
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

/** Create a {@link NameNode} proxy */
static DatanodeProtocolPB createNamenodeWithRetry(
    DatanodeProtocolPB rpcNamenode) {
  RetryPolicy createPolicy = RetryPolicies
      .retryUpToMaximumCountWithFixedSleep(5,
          HdfsConstants.LEASE_SOFTLIMIT_PERIOD, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>, RetryPolicy> remoteExceptionToPolicyMap = 
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class,
      createPolicy);

  Map<Class<? extends Exception>, RetryPolicy> exceptionToPolicyMap =
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class, RetryPolicies
      .retryByRemoteException(RetryPolicies.TRY_ONCE_THEN_FAIL,
          remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String, RetryPolicy> methodNameToPolicyMap = new HashMap<String, RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (DatanodeProtocolPB) RetryProxy.create(DatanodeProtocolPB.class,
      rpcNamenode, methodNameToPolicyMap);
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto req = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize)
      .build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

/** Create a {@link NameNode} proxy */
static DatanodeProtocolPB createNamenodeWithRetry(
    DatanodeProtocolPB rpcNamenode) {
  RetryPolicy createPolicy = RetryPolicies
      .retryUpToMaximumCountWithFixedSleep(5,
          HdfsConstants.LEASE_SOFTLIMIT_PERIOD, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>, RetryPolicy> remoteExceptionToPolicyMap = 
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class,
      createPolicy);

  Map<Class<? extends Exception>, RetryPolicy> exceptionToPolicyMap =
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class, RetryPolicies
      .retryByRemoteException(RetryPolicies.TRY_ONCE_THEN_FAIL,
          remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String, RetryPolicy> methodNameToPolicyMap = new HashMap<String, RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (DatanodeProtocolPB) RetryProxy.create(DatanodeProtocolPB.class,
      rpcNamenode, methodNameToPolicyMap);
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto req = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize)
      .build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

/** Create a {@link NameNode} proxy */
static DatanodeProtocolPB createNamenodeWithRetry(
    DatanodeProtocolPB rpcNamenode) {
  RetryPolicy createPolicy = RetryPolicies
      .retryUpToMaximumCountWithFixedSleep(5,
          HdfsConstants.LEASE_SOFTLIMIT_PERIOD, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>, RetryPolicy> remoteExceptionToPolicyMap = 
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class,
      createPolicy);

  Map<Class<? extends Exception>, RetryPolicy> exceptionToPolicyMap =
      new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class, RetryPolicies
      .retryByRemoteException(RetryPolicies.TRY_ONCE_THEN_FAIL,
          remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String, RetryPolicy> methodNameToPolicyMap = new HashMap<String, RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (DatanodeProtocolPB) RetryProxy.create(DatanodeProtocolPB.class,
      rpcNamenode, methodNameToPolicyMap);
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto req = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize)
      .build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

private static ClientProtocol createNamenode(ClientProtocol rpcNamenode)
  throws IOException {
  RetryPolicy createPolicy = RetryPolicies.retryUpToMaximumCountWithFixedSleep(
      5, LEASE_SOFTLIMIT_PERIOD, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>,RetryPolicy> remoteExceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class, createPolicy);

  Map<Class<? extends Exception>,RetryPolicy> exceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class, 
      RetryPolicies.retryByRemoteException(
          RetryPolicies.TRY_ONCE_THEN_FAIL, remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String,RetryPolicy> methodNameToPolicyMap = new HashMap<String,RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (ClientProtocol) RetryProxy.create(ClientProtocol.class,
      rpcNamenode, methodNameToPolicyMap);
}

/**
 * Mocks FSNamesystem instance, adds an empty file, sets status of last two
 * blocks to COMMITTED and COMMITTED and invokes lease recovery
 * method. AlreadyBeingCreatedException is expected.
 * @throws AlreadyBeingCreatedException as the result
 */
@Test(expected=AlreadyBeingCreatedException.class)
public void testInternalReleaseLease_COMM_COMM () throws IOException {
  if(LOG.isDebugEnabled()) {
    LOG.debug("Running " + GenericTestUtils.getMethodName());
  }
  LeaseManager.Lease lm = mock(LeaseManager.Lease.class);
  Path file = 
    spy(new Path("/" + GenericTestUtils.getMethodName() + "_test.dat"));
  DatanodeDescriptor dnd = mock(DatanodeDescriptor.class);
  PermissionStatus ps =
    new PermissionStatus("test", "test", new FsPermission((short)0777));

  mockFileBlocks(2, HdfsConstants.BlockUCState.COMMITTED, 
    HdfsConstants.BlockUCState.COMMITTED, file, dnd, ps, false);

  fsn.internalReleaseLease(lm, file.toString(), null);
  assertTrue("FSNamesystem.internalReleaseLease suppose to throw " +
    "AlreadyBeingCreatedException here", false);
}

/**
 * Mocks FSNamesystem instance, adds an empty file with 1 block
 * and invokes lease recovery method. 
 * AlreadyBeingCreatedException is expected.
 * @throws AlreadyBeingCreatedException as the result
 */
@Test(expected=AlreadyBeingCreatedException.class)
public void testInternalReleaseLease_1blocks () throws IOException {
  if(LOG.isDebugEnabled()) {
    LOG.debug("Running " + GenericTestUtils.getMethodName());
  }
  LeaseManager.Lease lm = mock(LeaseManager.Lease.class);
  Path file = 
    spy(new Path("/" + GenericTestUtils.getMethodName() + "_test.dat"));
  DatanodeDescriptor dnd = mock(DatanodeDescriptor.class);
  PermissionStatus ps =
    new PermissionStatus("test", "test", new FsPermission((short)0777));

  mockFileBlocks(1, null, HdfsConstants.BlockUCState.COMMITTED, file, dnd, ps, false);

  fsn.internalReleaseLease(lm, file.toString(), null);
  assertTrue("FSNamesystem.internalReleaseLease suppose to throw " +
    "AlreadyBeingCreatedException here", false);
}

private static ClientProtocol createNamenode(ClientProtocol rpcNamenode,
    Configuration conf)
  throws IOException {
  long sleepTime = conf.getLong("dfs.client.rpc.retry.sleep",
      LEASE_SOFTLIMIT_PERIOD);
  RetryPolicy createPolicy = RetryPolicies.retryUpToMaximumCountWithFixedSleep(
      5, sleepTime, TimeUnit.MILLISECONDS);

  Map<Class<? extends Exception>,RetryPolicy> remoteExceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  remoteExceptionToPolicyMap.put(AlreadyBeingCreatedException.class, createPolicy);

  Map<Class<? extends Exception>,RetryPolicy> exceptionToPolicyMap =
    new HashMap<Class<? extends Exception>, RetryPolicy>();
  exceptionToPolicyMap.put(RemoteException.class,
      RetryPolicies.retryByRemoteException(
          RetryPolicies.TRY_ONCE_THEN_FAIL, remoteExceptionToPolicyMap));
  RetryPolicy methodPolicy = RetryPolicies.retryByException(
      RetryPolicies.TRY_ONCE_THEN_FAIL, exceptionToPolicyMap);
  Map<String,RetryPolicy> methodNameToPolicyMap = new HashMap<String,RetryPolicy>();

  methodNameToPolicyMap.put("create", methodPolicy);

  return (ClientProtocol) RetryProxy.create(ClientProtocol.class,
      rpcNamenode, methodNameToPolicyMap);
}

/**
 * Takes ownership of the lock file if possible.
 * @param lockFile
 * @param lastEntry   last entry in the lock file. this param is an optimization.
 *                    we dont scan the lock file again to find its last entry here since
 *                    its already been done once by the logic used to check if the lock
 *                    file is stale. so this value comes from that earlier scan.
 * @param spoutId     spout id
 * @throws IOException if unable to acquire
 * @return null if lock File is not recoverable
 */
public static FileLock takeOwnership(FileSystem fs, Path lockFile, LogEntry lastEntry, String spoutId)
        throws IOException {
  try {
    if(fs instanceof DistributedFileSystem ) {
      if( !((DistributedFileSystem) fs).recoverLease(lockFile) ) {
        LOG.warn("Unable to recover lease on lock file {} right now. Cannot transfer ownership. Will need to try later. Spout = {}", lockFile, spoutId);
        return null;
      }
    }
    return new FileLock(fs, lockFile, spoutId, lastEntry);
  } catch (IOException e) {
    if (e instanceof RemoteException &&
            ((RemoteException) e).unwrapRemoteException() instanceof AlreadyBeingCreatedException) {
      LOG.warn("Lock file " + lockFile + "is currently open. Cannot transfer ownership now. Will need to try later. Spout= " + spoutId, e);
      return null;
    } else { // unexpected error
      LOG.warn("Cannot transfer ownership now for lock file " + lockFile + ". Will need to try later. Spout =" + spoutId, e);
      throw e;
    }
  }
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize, 
    CryptoProtocolVersion[] supportedVersions)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto.Builder builder = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize);
  builder.addAllCryptoProtocolVersion(PBHelper.convert(supportedVersions));
  CreateRequestProto req = builder.build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction. 
    fs2.append(p);

    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppend2Twice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final DistributedFileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {
    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction.
    ((DistributedFileSystem) fs2).append(p,
        EnumSet.of(CreateFlag.APPEND, CreateFlag.NEW_BLOCK), 4096, null);

    // 2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but does not have a BlockUnderConstructionFeature.
    fs2.append(p);

    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppend2Twice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final DistributedFileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {
    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but does not have a BlockUnderConstructionFeature.
    ((DistributedFileSystem) fs2).append(p,
        EnumSet.of(CreateFlag.APPEND, CreateFlag.NEW_BLOCK), 4096, null);

    // 2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize, 
    CryptoProtocolVersion[] supportedVersions)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto.Builder builder = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize);
  builder.addAllCryptoProtocolVersion(PBHelper.convert(supportedVersions));
  CreateRequestProto req = builder.build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction. 
    fs2.append(p);

    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppend2Twice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final DistributedFileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {
    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction.
    ((DistributedFileSystem) fs2).append(p,
        EnumSet.of(CreateFlag.APPEND, CreateFlag.NEW_BLOCK), 4096, null);

    // 2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

@Override
public HdfsFileStatus create(String src, FsPermission masked,
    String clientName, EnumSetWritable<CreateFlag> flag,
    boolean createParent, short replication, long blockSize, 
    CryptoProtocolVersion[] supportedVersions)
    throws AccessControlException, AlreadyBeingCreatedException,
    DSQuotaExceededException, FileAlreadyExistsException,
    FileNotFoundException, NSQuotaExceededException,
    ParentNotDirectoryException, SafeModeException, UnresolvedLinkException,
    IOException {
  CreateRequestProto.Builder builder = CreateRequestProto.newBuilder()
      .setSrc(src)
      .setMasked(PBHelper.convert(masked))
      .setClientName(clientName)
      .setCreateFlag(PBHelper.convertCreateFlag(flag))
      .setCreateParent(createParent)
      .setReplication(replication)
      .setBlockSize(blockSize);
  builder.addAllCryptoProtocolVersion(PBHelper.convert(supportedVersions));
  CreateRequestProto req = builder.build();
  try {
    CreateResponseProto res = rpcProxy.create(null, req);
    return res.hasFs() ? PBHelper.convert(res.getFs()) : null;
  } catch (ServiceException e) {
    throw ProtobufHelper.getRemoteException(e);
  }

}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction. 
    fs2.append(p);

    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}

private void recoverLeaseUsingCreate(Path filepath) throws IOException {
  Configuration conf2 = new Configuration(conf);
  String username = UserGroupInformation.getCurrentUGI().getUserName()+"_1";
  UnixUserGroupInformation.saveToConf(conf2,
      UnixUserGroupInformation.UGI_PROPERTY_NAME,
      new UnixUserGroupInformation(username, new String[]{"supergroup"}));
  FileSystem dfs2 = FileSystem.get(conf2);

  boolean done = false;
  for(int i = 0; i < 10 && !done; i++) {
    AppendTestUtil.LOG.info("i=" + i);
    try {
      dfs2.create(filepath, false, bufferSize, (short)1, BLOCK_SIZE);
      fail("Creation of an existing file should never succeed.");
    } catch (IOException ioe) {
      final String message = ioe.getMessage();
      if (message.contains("file exists")) {
        AppendTestUtil.LOG.info("done", ioe);
        done = true;
      }
      else if (message.contains(AlreadyBeingCreatedException.class.getSimpleName())) {
        AppendTestUtil.LOG.info("GOOD! got " + message);
      }
      else {
        AppendTestUtil.LOG.warn("UNEXPECTED IOException", ioe);
      }
    }

    if (!done) {
      AppendTestUtil.LOG.info("sleep " + 5000 + "ms");
      try {Thread.sleep(5000);} catch (InterruptedException e) {}
    }
  }
  assertTrue(done);

}

private void recoverLeaseUsingCreate(Path filepath) throws IOException {
  Configuration conf2 = new Configuration(conf);
  String username = UserGroupInformation.getCurrentUGI().getUserName()+"_1";
  UnixUserGroupInformation.saveToConf(conf2,
      UnixUserGroupInformation.UGI_PROPERTY_NAME,
      new UnixUserGroupInformation(username, new String[]{"supergroup"}));
  FileSystem dfs2 = FileSystem.get(conf2);

  boolean done = false;
  for(int i = 0; i < 10 && !done; i++) {
    AppendTestUtil.LOG.info("i=" + i);
    try {
      dfs2.create(filepath, false, bufferSize, (short)1, BLOCK_SIZE);
      fail("Creation of an existing file should never succeed.");
    } catch (IOException ioe) {
      final String message = ioe.getMessage();
      if (message.contains("file exists")) {
        AppendTestUtil.LOG.info("done", ioe);
        done = true;
      }
      else if (message.contains(AlreadyBeingCreatedException.class.getSimpleName())) {
        AppendTestUtil.LOG.info("GOOD! got " + message);
      }
      else {
        AppendTestUtil.LOG.warn("UNEXPECTED IOException", ioe);
      }
    }

    if (!done) {
      AppendTestUtil.LOG.info("sleep " + 5000 + "ms");
      try {Thread.sleep(5000);} catch (InterruptedException e) {}
    }
  }
  assertTrue(done);

}

private OutputStream checkAndMarkRunningBalancer() throws IOException {
  try {
    DataOutputStream out = fs.create(BALANCER_ID_PATH);
    out. writeBytes(InetAddress.getLocalHost().getHostName());
    out.flush();
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

private OutputStream checkAndMarkRunningBalancer() throws IOException {
  try {
    final DataOutputStream out = fs.create(BALANCER_ID_PATH);
    out.writeBytes(InetAddress.getLocalHost().getHostName());
    out.flush();
    return out;
  } catch(RemoteException e) {
    if(AlreadyBeingCreatedException.class.getName().equals(e.getClassName())){
      return null;
    } else {
      throw e;
    }
  }
}

/** Test two consecutive appends on a file with a full block. */
@Test
public void testAppendTwice() throws Exception {
  Configuration conf = new HdfsConfiguration();
  MiniDFSCluster cluster = new MiniDFSCluster.Builder(conf).build();
  final FileSystem fs1 = cluster.getFileSystem();
  final FileSystem fs2 = AppendTestUtil.createHdfsWithDifferentUsername(conf);
  try {

    final Path p = new Path("/testAppendTwice/foo");
    final int len = 1 << 16;
    final byte[] fileContents = AppendTestUtil.initBuffer(len);

    {
      // create a new file with a full block.
      FSDataOutputStream out = fs2.create(p, true, 4096, (short)1, len);
      out.write(fileContents, 0, len);
      out.close();
    }

    //1st append does not add any data so that the last block remains full
    //and the last block in INodeFileUnderConstruction is a BlockInfo
    //but not BlockInfoUnderConstruction. 
    fs2.append(p);

    //2nd append should get AlreadyBeingCreatedException
    fs1.append(p);
    Assert.fail();
  } catch(RemoteException re) {
    AppendTestUtil.LOG.info("Got an exception:", re);
    Assert.assertEquals(AlreadyBeingCreatedException.class.getName(),
        re.getClassName());
  } finally {
    fs2.close();
    fs1.close();
    cluster.shutdown();
  }
}