DFSClient (Apache Hadoop HDFS Client 3.4.1.300-dep-1001 API)

java.lang.Object
- org.apache.hadoop.hdfs.DFSClient

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, org.apache.hadoop.crypto.key.KeyProviderTokenIssuer, DataEncryptionKeyFactory, RemotePeerFactory, org.apache.hadoop.security.token.DelegationTokenIssuer
```
@Private
public class DFSClient
extends java.lang.Object
implements java.io.Closeable, RemotePeerFactory, DataEncryptionKeyFactory, org.apache.hadoop.crypto.key.KeyProviderTokenIssuer
```
DFSClient can connect to a Hadoop Filesystem and perform basic file tasks. It uses the ClientProtocol to communicate with a NameNode daemon, and connects directly to DataNodes to read/write block data. Hadoop DFS users should obtain an instance of DistributedFileSystem, which uses DFSClient to handle filesystem tasks.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

static class DFSClient.DFSDataInputStream
Deprecated.
use HdfsDataInputStream instead.

static class DFSClient.Renewer

Nested Classes
Modifier and Type	Class	Description
`static class`	`DFSClient.DFSDataInputStream`	Deprecated. use `HdfsDataInputStream` instead.
`static class`	`DFSClient.Renewer`

Field Summary

Fields
Modifier and Type Field Description

static org.slf4j.Logger LOG
- Fields inherited from interface org.apache.hadoop.security.token.DelegationTokenIssuer
  TOKEN_LOG

Fields
Modifier and Type	Field	Description
`static org.slf4j.Logger`	`LOG`

Constructor Summary

Constructors
Constructor	Description
`DFSClient(java.net.InetSocketAddress address, org.apache.hadoop.conf.Configuration conf)`
`DFSClient(java.net.URI nameNodeUri, org.apache.hadoop.conf.Configuration conf)`	Same as this(nameNodeUri, conf, null);
`DFSClient(java.net.URI nameNodeUri, org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem.Statistics stats)`	Same as this(nameNodeUri, null, conf, stats);
`DFSClient(java.net.URI nameNodeUri, ClientProtocol rpcNamenode, org.apache.hadoop.conf.Configuration conf, org.apache.hadoop.fs.FileSystem.Statistics stats)`	Create a new DFSClient connected to the given nameNodeUri or rpcNamenode.
`DFSClient(org.apache.hadoop.conf.Configuration conf)`	Deprecated. Deprecated at 0.21

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`long`	`addCacheDirective(CacheDirectiveInfo info, java.util.EnumSet<CacheFlag> flags)`
`void`	`addCachePool(CachePoolInfo info)`
`AddErasureCodingPolicyResponse[]`	`addErasureCodingPolicies(ErasureCodingPolicy[] policies)`
`void`	`addLocatedBlocksRefresh(DFSInputStream dfsInputStream)`	Adds the `DFSInputStream` to the `LocatedBlocksRefresher`, so that the underlying `LocatedBlocks` is periodically refreshed.
`void`	`addNodeToDeadNodeDetector(DFSInputStream dfsInputStream, DatanodeInfo datanodeInfo)`	Add given datanode in DeadNodeDetector.
`void`	`allowSnapshot(java.lang.String snapshotRoot)`	Allow snapshot on a directory.
`HdfsDataOutputStream`	`append(java.lang.String src, int buffersize, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, org.apache.hadoop.util.Progressable progress, org.apache.hadoop.fs.FileSystem.Statistics statistics)`	Append to an existing HDFS file.
`HdfsDataOutputStream`	`append(java.lang.String src, int buffersize, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, org.apache.hadoop.util.Progressable progress, org.apache.hadoop.fs.FileSystem.Statistics statistics, java.net.InetSocketAddress[] favoredNodes)`	Append to an existing HDFS file.
`BatchedDirectoryListing`	`batchedListPaths(java.lang.String[] srcs, byte[] startAfter, boolean needLocation)`	Get a batched listing for the indicated directories
`void`	`cancelDelegationToken(org.apache.hadoop.security.token.Token<DelegationTokenIdentifier> token)`	Deprecated. Use Token.cancel instead.
`void`	`checkAccess(java.lang.String src, org.apache.hadoop.fs.permission.FsAction mode)`
`void`	`clearDataEncryptionKey()`
`void`	`close()`	Close the file system, abandoning all of the leases and files being created and close connections to the namenode.
`void`	`closeAllFilesBeingWritten(boolean abort)`	Close/abort all files being written.
`void`	`closeOutputStreams(boolean abort)`	Close all open streams, abandoning all of the leases and files being created.
`void`	`concat(java.lang.String trg, java.lang.String[] srcs)`	Move blocks from src to trg and delete src See `ClientProtocol.concat(java.lang.String, java.lang.String[])`.
`protected IOStreamPair`	`connectToDN(DatanodeInfo dn, int timeout, org.apache.hadoop.security.token.Token<BlockTokenIdentifier> blockToken)`
`java.io.OutputStream`	`create(java.lang.String src, boolean overwrite)`	Call `create(String, boolean, short, long, Progressable)` with default `replication` and `blockSize` and null `progress`.
`java.io.OutputStream`	`create(java.lang.String src, boolean overwrite, short replication, long blockSize)`	Call `create(String, boolean, short, long, Progressable)` with null `progress`.
`java.io.OutputStream`	`create(java.lang.String src, boolean overwrite, short replication, long blockSize, org.apache.hadoop.util.Progressable progress)`	Call `create(String, boolean, short, long, Progressable, int)` with default bufferSize.
`java.io.OutputStream`	`create(java.lang.String src, boolean overwrite, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize)`	Call `create(String, FsPermission, EnumSet, short, long, Progressable, int, ChecksumOpt)` with default `permission` `FsPermission.getFileDefault()`.
`java.io.OutputStream`	`create(java.lang.String src, boolean overwrite, org.apache.hadoop.util.Progressable progress)`	Call `create(String, boolean, short, long, Progressable)` with default `replication` and `blockSize`.
`DFSOutputStream`	`create(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, boolean createParent, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)`	Create a new dfs file with the specified block replication with write-progress reporting and return an output stream for writing into the file.
`DFSOutputStream`	`create(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, boolean createParent, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt, java.net.InetSocketAddress[] favoredNodes)`	Same as `create(String, FsPermission, EnumSet, boolean, short, long, Progressable, int, ChecksumOpt)` with the addition of favoredNodes that is a hint to where the namenode should place the file blocks.
`DFSOutputStream`	`create(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, boolean createParent, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt, java.net.InetSocketAddress[] favoredNodes, java.lang.String ecPolicyName)`	Same as `create(String, FsPermission, EnumSet, boolean, short, long, Progressable, int, ChecksumOpt, InetSocketAddress[])` with the addition of ecPolicyName that is used to specify a specific erasure coding policy instead of inheriting any policy from this new file's parent directory.
`DFSOutputStream`	`create(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, boolean createParent, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt, java.net.InetSocketAddress[] favoredNodes, java.lang.String ecPolicyName, java.lang.String storagePolicy)`	Same as `create(String, FsPermission, EnumSet, boolean, short, long, Progressable, int, ChecksumOpt, InetSocketAddress[], String)` with the storagePolicy that is used to specify a specific storage policy instead of inheriting any policy from this new file's parent directory.
`DFSOutputStream`	`create(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)`	Call `create(String, FsPermission, EnumSet, boolean, short, long, Progressable, int, ChecksumOpt)` with `createParent` set to true.
`void`	`createEncryptionZone(java.lang.String src, java.lang.String keyName)`
`java.lang.String`	`createSnapshot(java.lang.String snapshotRoot, java.lang.String snapshotName)`	Create one snapshot.
`void`	`createSymlink(java.lang.String target, java.lang.String link, boolean createParent)`	Creates a symbolic link.
`HdfsDataInputStream`	`createWrappedInputStream(DFSInputStream dfsis)`	Wraps the stream in a CryptoInputStream if the underlying file is encrypted.
`HdfsDataOutputStream`	`createWrappedOutputStream(DFSOutputStream dfsos, org.apache.hadoop.fs.FileSystem.Statistics statistics)`	Wraps the stream in a CryptoOutputStream if the underlying file is encrypted.
`HdfsDataOutputStream`	`createWrappedOutputStream(DFSOutputStream dfsos, org.apache.hadoop.fs.FileSystem.Statistics statistics, long startPos)`	Wraps the stream in a CryptoOutputStream if the underlying file is encrypted.
`DatanodeInfo[]`	`datanodeReport(HdfsConstants.DatanodeReportType type)`
`boolean`	`delete(java.lang.String src)`	Deprecated.
`boolean`	`delete(java.lang.String src, boolean recursive)`	delete file or directory.
`void`	`deleteSnapshot(java.lang.String snapshotRoot, java.lang.String snapshotName)`	Delete a snapshot of a snapshottable directory.
`void`	`disableErasureCodingPolicy(java.lang.String ecPolicyName)`
`void`	`disallowSnapshot(java.lang.String snapshotRoot)`	Disallow snapshot on a directory.
`void`	`enableErasureCodingPolicy(java.lang.String ecPolicyName)`
`boolean`	`exists(java.lang.String src)`	Implemented using getFileInfo(src)
`void`	`finalizeUpgrade()`
`org.apache.hadoop.fs.permission.AclStatus`	`getAclStatus(java.lang.String src)`
`protected LocatedBlocks`	`getBlockLocations(java.lang.String src, long length)`
`org.apache.hadoop.fs.BlockLocation[]`	`getBlockLocations(java.lang.String src, long start, long length)`	Get block location info about file getBlockLocations() returns a list of hostnames that store data for a specific file region.
`long`	`getBlockSize(java.lang.String f)`
`long`	`getBytesInFutureBlocks()`	Returns number of bytes that reside in Blocks with future generation stamps.
`java.lang.String`	`getCanonicalServiceName()`	Get a canonical token service name for this client's tokens.
`ClientContext`	`getClientContext()`
`java.lang.String`	`getClientName()`
`DfsClientConf`	`getConf()`
`long`	`getCorruptBlocksCount()`	Returns count of blocks with at least one replica marked corrupt.
`DatanodeStorageReport[]`	`getDatanodeStorageReport(HdfsConstants.DatanodeReportType type)`
`DeadNodeDetector`	`getDeadNodeDetector()`	Obtain DeadNodeDetector of the current client.
`java.util.concurrent.ConcurrentHashMap<DatanodeInfo,DatanodeInfo>`	`getDeadNodes(DFSInputStream dfsInputStream)`	If deadNodeDetectionEnabled is true, return the dead nodes that detected by all the DFSInputStreams in the same client.
`CachingStrategy`	`getDefaultReadCachingStrategy()`
`CachingStrategy`	`getDefaultWriteCachingStrategy()`
`org.apache.hadoop.security.token.Token<?>`	`getDelegationToken(java.lang.String renewer)`
`org.apache.hadoop.security.token.Token<DelegationTokenIdentifier>`	`getDelegationToken(org.apache.hadoop.io.Text renewer)`
`org.apache.hadoop.fs.FsStatus`	`getDiskStatus()`
`ECTopologyVerifierResult`	`getECTopologyResultForPolicies(java.lang.String... policyNames)`
`org.apache.hadoop.fs.Path`	`getEnclosingRoot(java.lang.String src)`
`DataEncryptionKey`	`getEncryptionKey()`
`java.util.Map<java.lang.String,java.lang.String>`	`getErasureCodingCodecs()`
`ErasureCodingPolicyInfo[]`	`getErasureCodingPolicies()`
`ErasureCodingPolicy`	`getErasureCodingPolicy(java.lang.String src)`	Get the erasure coding policy information for the specified path
`EncryptionZone`	`getEZForPath(java.lang.String src)`
`org.apache.hadoop.fs.MD5MD5CRC32FileChecksum`	`getFileChecksum(java.lang.String src, long length)`	Get the checksum of the whole file or a range of the file.
`org.apache.hadoop.fs.FileChecksum`	`getFileChecksumWithCombineMode(java.lang.String src, long length)`	Get the checksum of the whole file or a range of the file.
`HdfsFileStatus`	`getFileInfo(java.lang.String src)`	Get the file info for a specific file or directory.
`HdfsFileStatus`	`getFileLinkInfo(java.lang.String src)`	Get the file info for a specific file or directory.
`org.apache.hadoop.ha.HAServiceProtocol.HAServiceState`	`getHAServiceState()`	An unblocking call to get the HA service state of NameNode.
`DFSInotifyEventInputStream`	`getInotifyEventStream()`
`DFSInotifyEventInputStream`	`getInotifyEventStream(long lastReadTxid)`
`org.apache.hadoop.crypto.key.KeyProvider`	`getKeyProvider()`
`java.net.URI`	`getKeyProviderUri()`
`LeaseRenewer`	`getLeaseRenewer()`	Return the lease renewer instance.
`java.lang.String`	`getLinkTarget(java.lang.String path)`	Resolve the first symlink, if any, in the path.
`LocatedBlocksRefresher`	`getLocatedBlockRefresher()`	Obtain LocatedBlocksRefresher of the current client.
`LocatedBlocks`	`getLocatedBlocks(java.lang.String src, long start)`	Get locations of the blocks of the specified file `src` from offset `start` within the prefetch size which is related to parameter `dfs.client.read.prefetch.size`.
`LocatedBlocks`	`getLocatedBlocks(java.lang.String src, long start, long length)`	This is just a wrapper around callGetBlockLocations, but non-static so that we can stub it out for tests.
`HdfsLocatedFileStatus`	`getLocatedFileInfo(java.lang.String src, boolean needBlockToken)`	Get the file info for a specific file or directory.
`long`	`getLowRedundancyBlocksCount()`	Returns aggregated count of blocks with less redundancy.
`long`	`getMissingBlocksCount()`	Returns count of blocks with no good replicas left.
`long`	`getMissingReplOneBlocksCount()`	Returns count of blocks with replication factor 1 and have lost the only replica.
`ClientProtocol`	`getNamenode()`	Get the namenode associated with this DFSClient object
`int`	`getNumOfFilesBeingWritten()`
`long`	`getPendingDeletionBlocksCount()`	Returns count of blocks pending on deletion.
`long`	`getRefreshReadBlkLocationsInterval()`
`SaslDataTransferClient`	`getSaslDataTransferClient()`	Returns the SaslDataTransferClient configured for this DFSClient.
`org.apache.hadoop.fs.FsServerDefaults`	`getServerDefaults()`	Get server default values for a number of configuration params.
`SnapshotDiffReport`	`getSnapshotDiffReport(java.lang.String snapshotDir, java.lang.String fromSnapshot, java.lang.String toSnapshot)`	Get the difference between two snapshots, or between a snapshot and the current tree of a directory.
`SnapshotDiffReportListing`	`getSnapshotDiffReportListing(java.lang.String snapshotDir, java.lang.String fromSnapshot, java.lang.String toSnapshot, byte[] startPath, int index)`	Get the difference between two snapshots of a directory iteratively.
`SnapshotStatus[]`	`getSnapshotListing(java.lang.String snapshotRoot)`	Get listing of all the snapshots for a snapshottable directory.
`SnapshottableDirectoryStatus[]`	`getSnapshottableDirListing()`	Get all the current snapshottable directories.
`static long`	`getStateAtIndex(long[] states, int index)`
`BlockStoragePolicy[]`	`getStoragePolicies()`
`BlockStoragePolicy`	`getStoragePolicy(java.lang.String path)`
`byte[]`	`getXAttr(java.lang.String src, java.lang.String name)`
`java.util.Map<java.lang.String,byte[]>`	`getXAttrs(java.lang.String src)`
`java.util.Map<java.lang.String,byte[]>`	`getXAttrs(java.lang.String src, java.util.List<java.lang.String> names)`
`protected org.apache.hadoop.util.DataChecksum.Type`	`inferChecksumTypeByReading(LocatedBlock lb, DatanodeInfo dn)`	Infer the checksum type for a replica by sending an OP_READ_BLOCK for the first byte of that replica.
`boolean`	`isClientRunning()`
`boolean`	`isDeadNode(DFSInputStream dfsInputStream, DatanodeInfo datanodeInfo)`	If deadNodeDetectionEnabled is true, judgement based on whether this datanode is included or not in DeadNodeDetector.
`boolean`	`isFileClosed(java.lang.String src)`	Close status of a file
`boolean`	`isFilesBeingWrittenEmpty()`	Is file-being-written map empty?
`org.apache.hadoop.fs.RemoteIterator<CacheDirectiveEntry>`	`listCacheDirectives(CacheDirectiveInfo filter)`
`org.apache.hadoop.fs.RemoteIterator<CachePoolEntry>`	`listCachePools()`
`CorruptFileBlocks`	`listCorruptFileBlocks(java.lang.String path, java.lang.String cookie)`
`org.apache.hadoop.fs.RemoteIterator<EncryptionZone>`	`listEncryptionZones()`
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles()`	Deprecated.
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles(java.lang.String path)`	Get a remote iterator to the open files list by path, managed by NameNode.
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes)`	Get a remote iterator to the open files list by type, managed by NameNode.
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes, java.lang.String path)`	Get a remote iterator to the open files list by type and path, managed by NameNode.
`DirectoryListing`	`listPaths(java.lang.String src, byte[] startAfter)`	Get a partial listing of the indicated directory No block locations need to be fetched
`DirectoryListing`	`listPaths(java.lang.String src, byte[] startAfter, boolean needLocation)`	Get a partial listing of the indicated directory Recommend to use HdfsFileStatus.EMPTY_NAME as startAfter if the application wants to fetch a listing starting from the first entry in the directory
`org.apache.hadoop.fs.RemoteIterator<ZoneReencryptionStatus>`	`listReencryptionStatus()`
`java.util.List<java.lang.String>`	`listXAttrs(java.lang.String src)`
`void`	`metaSave(java.lang.String pathname)`	Dumps DFS data structures into specified file.
`boolean`	`mkdirs(java.lang.String src)`	Deprecated.
`boolean`	`mkdirs(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission, boolean createParent)`	Create a directory (or hierarchy of directories) with the given name and permission.
`void`	`modifyAclEntries(java.lang.String src, java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)`
`void`	`modifyCacheDirective(CacheDirectiveInfo info, java.util.EnumSet<CacheFlag> flags)`
`void`	`modifyCachePool(CachePoolInfo info)`
`void`	`msync()`	A blocking call to wait for Observer NameNode state ID to reach to the current client state ID.
`Peer`	`newConnectedPeer(java.net.InetSocketAddress addr, org.apache.hadoop.security.token.Token<BlockTokenIdentifier> blockToken, DatanodeID datanodeId)`
`DataEncryptionKey`	`newDataEncryptionKey()`	Creates a new DataEncryptionKey.
`DFSInputStream`	`open(java.lang.String src)`
`DFSInputStream`	`open(java.lang.String src, int buffersize, boolean verifyChecksum)`	Create an input stream that obtains a nodelist from the namenode, and then reads from all the right places.
`DFSInputStream`	`open(java.lang.String src, int buffersize, boolean verifyChecksum, org.apache.hadoop.fs.FileSystem.Statistics stats)`	Deprecated. Use `open(String, int, boolean)` instead.
`DFSInputStream`	`open(HdfsPathHandle fd, int buffersize, boolean verifyChecksum)`	Create an input stream from the `HdfsPathHandle` if the constraints encoded from `DistributedFileSystem.createPathHandle(FileStatus, Options.HandleOpt...)` are satisfied.
`DFSOutputStream`	`primitiveCreate(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission absPermission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, boolean createParent, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, int buffersize, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)`	Same as {`create(String, FsPermission, EnumSet, short, long, Progressable, int, ChecksumOpt)` except that the permission is absolute (ie has already been masked with umask.
`boolean`	`primitiveMkdir(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission absPermission)`	Same {`mkdirs(String, FsPermission, boolean)` except that the permissions has already been masked against umask.
`boolean`	`primitiveMkdir(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission absPermission, boolean createParent)`	Same {`mkdirs(String, FsPermission, boolean)` except that the permissions has already been masked against umask.
`void`	`putFileBeingWritten(java.lang.String key, DFSOutputStream out)`	Put a file.
`void`	`reencryptEncryptionZone(java.lang.String zone, HdfsConstants.ReencryptAction action)`
`void`	`refreshNodes()`	Refresh the hosts and exclude files.
`void`	`removeAcl(java.lang.String src)`
`void`	`removeAclEntries(java.lang.String src, java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)`
`void`	`removeCacheDirective(long id)`
`void`	`removeCachePool(java.lang.String poolName)`
`void`	`removeDefaultAcl(java.lang.String src)`
`void`	`removeErasureCodingPolicy(java.lang.String ecPolicyName)`
`void`	`removeFileBeingWritten(java.lang.String key)`	Remove a file.
`void`	`removeLocatedBlocksRefresh(DFSInputStream dfsInputStream)`	Removes the `DFSInputStream` from the `LocatedBlocksRefresher`, so that the underlying `LocatedBlocks` is no longer periodically refreshed.
`void`	`removeNodeFromDeadNodeDetector(DFSInputStream dfsInputStream, DatanodeInfo datanodeInfo)`	Remove given datanode from DeadNodeDetector.
`void`	`removeNodeFromDeadNodeDetector(DFSInputStream dfsInputStream, LocatedBlocks locatedBlocks)`	Remove datanodes that given block placed on from DeadNodeDetector.
`void`	`removeXAttr(java.lang.String src, java.lang.String name)`
`boolean`	`rename(java.lang.String src, java.lang.String dst)`	Deprecated. Use `rename(String, String, Options.Rename...)` instead.
`void`	`rename(java.lang.String src, java.lang.String dst, org.apache.hadoop.fs.Options.Rename... options)`	Rename file or directory.
`void`	`renameSnapshot(java.lang.String snapshotDir, java.lang.String snapshotOldName, java.lang.String snapshotNewName)`	Rename a snapshot.
`long`	`renewDelegationToken(org.apache.hadoop.security.token.Token<DelegationTokenIdentifier> token)`	Deprecated. Use Token.renew instead.
`boolean`	`renewLease()`	Renew leases.
`void`	`reportBadBlocks(LocatedBlock[] blocks)`	Report corrupt blocks that were discovered by the client.
`void`	`satisfyStoragePolicy(java.lang.String src)`	Satisfy storage policy for an existing file/directory.
`void`	`setAcl(java.lang.String src, java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)`
`void`	`setBalancerBandwidth(long bandwidth)`	Requests the namenode to tell all datanodes to use a new, non-persistent bandwidth value for dfs.datanode.balance.bandwidthPerSec.
`static void`	`setDisabledStopDeadNodeDetectorThreadForTest(boolean disabledStopDeadNodeDetectorThreadForTest)`
`void`	`setErasureCodingPolicy(java.lang.String src, java.lang.String ecPolicyName)`
`void`	`setKeyProvider(org.apache.hadoop.crypto.key.KeyProvider provider)`
`void`	`setOwner(java.lang.String src, java.lang.String username, java.lang.String groupname)`	Set file or directory owner.
`void`	`setPermission(java.lang.String src, org.apache.hadoop.fs.permission.FsPermission permission)`	Set permissions to a file or directory.
`boolean`	`setReplication(java.lang.String src, short replication)`	Set replication for an existing file.
`boolean`	`setSafeMode(HdfsConstants.SafeModeAction action)`	Enter, leave or get safe mode.
`boolean`	`setSafeMode(HdfsConstants.SafeModeAction action, boolean isChecked)`	Enter, leave or get safe mode.
`void`	`setStoragePolicy(java.lang.String src, java.lang.String policyName)`	Set storage policy for an existing file/directory
`void`	`setTimes(java.lang.String src, long mtime, long atime)`	set the modification and access time of a file.
`void`	`setXAttr(java.lang.String src, java.lang.String name, byte[] value, java.util.EnumSet<org.apache.hadoop.fs.XAttrSetFlag> flag)`
`DatanodeInfo[]`	`slowDatanodeReport()`
`java.lang.String`	`toString()`
`boolean`	`truncate(java.lang.String src, long newLength)`	Truncate a file to an indicated size See `ClientProtocol.truncate(java.lang.String, long, java.lang.String)`.
`void`	`unsetErasureCodingPolicy(java.lang.String src)`
`void`	`unsetStoragePolicy(java.lang.String src)`	Unset storage policy set for a given file/directory.
`boolean`	`upgradeStatus()`

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface org.apache.hadoop.security.token.DelegationTokenIssuer
addDelegationTokens, getAdditionalTokenIssuers

Field Detail

LOG

public static final org.slf4j.Logger LOG

Constructor Detail

DFSClient
```
@Deprecated
public DFSClient(org.apache.hadoop.conf.Configuration conf)
          throws java.io.IOException
```
Deprecated.
Deprecated at 0.21

Same as this(NameNode.getNNAddress(conf), conf);

Throws:

java.io.IOException

See Also:

DFSClient(InetSocketAddress, Configuration)

DFSClient

public DFSClient(java.net.InetSocketAddress address,
                 org.apache.hadoop.conf.Configuration conf)
          throws java.io.IOException

Throws:: java.io.IOException

DFSClient

public DFSClient(java.net.URI nameNodeUri,
                 org.apache.hadoop.conf.Configuration conf)
          throws java.io.IOException

Same as this(nameNodeUri, conf, null);

Throws:: java.io.IOException
See Also:: DFSClient(URI, Configuration, FileSystem.Statistics)

DFSClient

public DFSClient(java.net.URI nameNodeUri,
                 org.apache.hadoop.conf.Configuration conf,
                 org.apache.hadoop.fs.FileSystem.Statistics stats)
          throws java.io.IOException

Same as this(nameNodeUri, null, conf, stats);

Throws:: java.io.IOException
See Also:: DFSClient(URI, ClientProtocol, Configuration, FileSystem.Statistics)

DFSClient
```
@VisibleForTesting
public DFSClient(java.net.URI nameNodeUri,
                 ClientProtocol rpcNamenode,
                 org.apache.hadoop.conf.Configuration conf,
                 org.apache.hadoop.fs.FileSystem.Statistics stats)
          throws java.io.IOException
```
Create a new DFSClient connected to the given nameNodeUri or rpcNamenode. If HA is enabled and a positive value is set for HdfsClientConfigKeys.DFS_CLIENT_TEST_DROP_NAMENODE_RESPONSE_NUM_KEY in the configuration, the DFSClient will use LossyRetryInvocationHandler as its RetryInvocationHandler. Otherwise one of nameNodeUri or rpcNamenode must be null.

Throws:

java.io.IOException

Method Detail

setDisabledStopDeadNodeDetectorThreadForTest

@VisibleForTesting
public static void setDisabledStopDeadNodeDetectorThreadForTest(boolean disabledStopDeadNodeDetectorThreadForTest)

getConf
```
public DfsClientConf getConf()
```

getClientName

@VisibleForTesting
public java.lang.String getClientName()

getLeaseRenewer
```
public LeaseRenewer getLeaseRenewer()
```
Return the lease renewer instance. The renewer thread won't start until the first output stream is created. The same instance will be returned until all output streams are closed.

putFileBeingWritten
```
public void putFileBeingWritten(java.lang.String key,
                                DFSOutputStream out)
```
Put a file. Only called from LeaseRenewer, where proper locking is enforced to consistently update its local dfsclients array and client's filesBeingWritten map.

removeFileBeingWritten
```
public void removeFileBeingWritten(java.lang.String key)
```
Remove a file. Only called from LeaseRenewer.

isFilesBeingWrittenEmpty
```
public boolean isFilesBeingWrittenEmpty()
```
Is file-being-written map empty?

isClientRunning
```
public boolean isClientRunning()
```
Returns:

true if the client is running

getNumOfFilesBeingWritten

@VisibleForTesting
public int getNumOfFilesBeingWritten()

renewLease
```
public boolean renewLease()
                   throws java.io.IOException
```
Renew leases.

Returns:

true if lease was renewed. May return false if this client has been closed or has no files open.

Throws:

java.io.IOException

closeAllFilesBeingWritten
```
public void closeAllFilesBeingWritten(boolean abort)
```
Close/abort all files being written.

close
```
public void close()
           throws java.io.IOException
```
Close the file system, abandoning all of the leases and files being created and close connections to the namenode.

Specified by:

close in interface java.lang.AutoCloseable

Specified by:

close in interface java.io.Closeable

Throws:

java.io.IOException

closeOutputStreams
```
public void closeOutputStreams(boolean abort)
```
Close all open streams, abandoning all of the leases and files being created.

Parameters:

abort - whether streams should be gracefully closed

getBlockSize

public long getBlockSize(java.lang.String f)
                  throws java.io.IOException

Throws:: java.io.IOException
See Also:: ClientProtocol.getPreferredBlockSize(String)

getServerDefaults

public org.apache.hadoop.fs.FsServerDefaults getServerDefaults()
                                                        throws java.io.IOException

Get server default values for a number of configuration params.

Throws:: java.io.IOException
See Also:: ClientProtocol.getServerDefaults()

getCanonicalServiceName
```
@LimitedPrivate("HDFS")
public java.lang.String getCanonicalServiceName()
```
Get a canonical token service name for this client's tokens. Null should be returned if the client is not using tokens.

Specified by:

getCanonicalServiceName in interface org.apache.hadoop.security.token.DelegationTokenIssuer

Returns:

the token service for the client

getDelegationToken

public org.apache.hadoop.security.token.Token<?> getDelegationToken(java.lang.String renewer)
                                                             throws java.io.IOException

Specified by:: getDelegationToken in interface org.apache.hadoop.security.token.DelegationTokenIssuer
Throws:: java.io.IOException

getDelegationToken

public org.apache.hadoop.security.token.Token<DelegationTokenIdentifier> getDelegationToken(org.apache.hadoop.io.Text renewer)
                                                                                     throws java.io.IOException

Throws:: java.io.IOException
See Also:: ClientProtocol.getDelegationToken(Text)

renewDelegationToken

@Deprecated
public long renewDelegationToken(org.apache.hadoop.security.token.Token<DelegationTokenIdentifier> token)
                          throws java.io.IOException

Deprecated.

Use Token.renew instead.

Renew a delegation token

Parameters:: token - the token to renew
Returns:: the new expiration time
Throws:: java.io.IOException

cancelDelegationToken

@Deprecated
public void cancelDelegationToken(org.apache.hadoop.security.token.Token<DelegationTokenIdentifier> token)
                           throws java.io.IOException

Deprecated.

Use Token.cancel instead.

Cancel a delegation token

Parameters:: token - the token to cancel
Throws:: java.io.IOException

reportBadBlocks
```
public void reportBadBlocks(LocatedBlock[] blocks)
                     throws java.io.IOException
```
Report corrupt blocks that were discovered by the client.

Throws:

java.io.IOException

See Also:

ClientProtocol.reportBadBlocks(LocatedBlock[])

getRefreshReadBlkLocationsInterval

public long getRefreshReadBlkLocationsInterval()

getLocatedBlocks
```
public LocatedBlocks getLocatedBlocks(java.lang.String src,
                                      long start)
                               throws java.io.IOException
```
Get locations of the blocks of the specified file `src` from offset `start` within the prefetch size which is related to parameter `dfs.client.read.prefetch.size`. DataNode locations for each block are sorted by the proximity to the client. Please note that the prefetch size is not equal file length generally.

Parameters:

src - the file path.

start - starting offset.

Returns:

LocatedBlocks

Throws:

java.io.IOException

getLocatedBlocks

@VisibleForTesting
public LocatedBlocks getLocatedBlocks(java.lang.String src,
                                      long start,
                                      long length)
                               throws java.io.IOException

This is just a wrapper around callGetBlockLocations, but non-static so that we can stub it out for tests.

Throws:: java.io.IOException

getBlockLocations
```
public org.apache.hadoop.fs.BlockLocation[] getBlockLocations(java.lang.String src,
                                                              long start,
                                                              long length)
                                                       throws java.io.IOException
```
Get block location info about file getBlockLocations() returns a list of hostnames that store data for a specific file region. It returns a set of hostnames for every block within the indicated region. This function is very useful when writing code that considers data-placement when performing operations. For example, the MapReduce system tries to schedule tasks on the same machines as the data-block the task processes. Please refer to FileSystem.getFileBlockLocations(FileStatus, long, long) for more details.

Throws:

java.io.IOException

createWrappedInputStream

public HdfsDataInputStream createWrappedInputStream(DFSInputStream dfsis)
                                             throws java.io.IOException

Wraps the stream in a CryptoInputStream if the underlying file is encrypted.

Throws:: java.io.IOException

createWrappedOutputStream

public HdfsDataOutputStream createWrappedOutputStream(DFSOutputStream dfsos,
                                                      org.apache.hadoop.fs.FileSystem.Statistics statistics)
                                               throws java.io.IOException

Wraps the stream in a CryptoOutputStream if the underlying file is encrypted.

Throws:: java.io.IOException

createWrappedOutputStream

public HdfsDataOutputStream createWrappedOutputStream(DFSOutputStream dfsos,
                                                      org.apache.hadoop.fs.FileSystem.Statistics statistics,
                                                      long startPos)
                                               throws java.io.IOException

Wraps the stream in a CryptoOutputStream if the underlying file is encrypted.

Throws:: java.io.IOException

open

public DFSInputStream open(java.lang.String src)
                    throws java.io.IOException

Throws:: java.io.IOException

open

@Deprecated
public DFSInputStream open(java.lang.String src,
                           int buffersize,
                           boolean verifyChecksum,
                           org.apache.hadoop.fs.FileSystem.Statistics stats)
                    throws java.io.IOException

Deprecated.

Use open(String, int, boolean) instead.

Create an input stream that obtains a nodelist from the namenode, and then reads from all the right places. Creates inner subclass of InputStream that does the right out-of-band work.

Throws:: java.io.IOException

open
```
public DFSInputStream open(java.lang.String src,
                           int buffersize,
                           boolean verifyChecksum)
                    throws java.io.IOException
```
Create an input stream that obtains a nodelist from the namenode, and then reads from all the right places. Creates inner subclass of InputStream that does the right out-of-band work.

Throws:

java.io.IOException

open
```
public DFSInputStream open(HdfsPathHandle fd,
                           int buffersize,
                           boolean verifyChecksum)
                    throws java.io.IOException
```
Create an input stream from the HdfsPathHandle if the constraints encoded from DistributedFileSystem.createPathHandle(FileStatus, Options.HandleOpt...) are satisfied. Note that HDFS does not ensure that these constraints remain invariant for the life of the stream. It only checks that they still held when the stream was opened.

Parameters:

fd - Handle to an entity in HDFS, with constraints

buffersize - ignored

verifyChecksum - Verify checksums before returning data to client

Returns:

Data from the referent of the HdfsPathHandle.

Throws:

java.io.IOException - On I/O error

getNamenode
```
public ClientProtocol getNamenode()
```
Get the namenode associated with this DFSClient object

Returns:

the namenode associated with this DFSClient object

create

public java.io.OutputStream create(java.lang.String src,
                                   boolean overwrite)
                            throws java.io.IOException

Call create(String, boolean, short, long, Progressable) with default replication and blockSize and null progress.

Throws:: java.io.IOException

create

public java.io.OutputStream create(java.lang.String src,
                                   boolean overwrite,
                                   org.apache.hadoop.util.Progressable progress)
                            throws java.io.IOException

Call create(String, boolean, short, long, Progressable) with default replication and blockSize.

Throws:: java.io.IOException

create

public java.io.OutputStream create(java.lang.String src,
                                   boolean overwrite,
                                   short replication,
                                   long blockSize)
                            throws java.io.IOException

Call create(String, boolean, short, long, Progressable) with null progress.

Throws:: java.io.IOException

create

public java.io.OutputStream create(java.lang.String src,
                                   boolean overwrite,
                                   short replication,
                                   long blockSize,
                                   org.apache.hadoop.util.Progressable progress)
                            throws java.io.IOException

Call create(String, boolean, short, long, Progressable, int) with default bufferSize.

Throws:: java.io.IOException

create
```
public java.io.OutputStream create(java.lang.String src,
                                   boolean overwrite,
                                   short replication,
                                   long blockSize,
                                   org.apache.hadoop.util.Progressable progress,
                                   int buffersize)
                            throws java.io.IOException
```
Call create(String, FsPermission, EnumSet, short, long, Progressable, int, ChecksumOpt) with default permission FsPermission.getFileDefault().

Parameters:

src - File name

overwrite - overwrite an existing file if true

replication - replication factor for the file

blockSize - maximum block size

progress - interface for reporting client progress

buffersize - underlying buffersize

Returns:

output stream

Throws:

java.io.IOException

create

public DFSOutputStream create(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission permission,
                              java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                              short replication,
                              long blockSize,
                              org.apache.hadoop.util.Progressable progress,
                              int buffersize,
                              org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)
                       throws java.io.IOException

Call

create(String, FsPermission, EnumSet, boolean, short,
 long, Progressable, int, ChecksumOpt)

with createParent set to true.

Throws:: java.io.IOException

create
```
public DFSOutputStream create(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission permission,
                              java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                              boolean createParent,
                              short replication,
                              long blockSize,
                              org.apache.hadoop.util.Progressable progress,
                              int buffersize,
                              org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)
                       throws java.io.IOException
```
Create a new dfs file with the specified block replication with write-progress reporting and return an output stream for writing into the file.

Parameters:

src - File name

permission - The permission of the directory being created. If null, use default permission FsPermission.getFileDefault()

flag - indicates create a new file or create/overwrite an existing file or append to an existing file

createParent - create missing parent directory if true

replication - block replication

blockSize - maximum block size

progress - interface for reporting client progress

buffersize - underlying buffer size

checksumOpt - checksum options

Returns:

output stream

Throws:

java.io.IOException

See Also:

for detailed description of exceptions thrown

create

public DFSOutputStream create(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission permission,
                              java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                              boolean createParent,
                              short replication,
                              long blockSize,
                              org.apache.hadoop.util.Progressable progress,
                              int buffersize,
                              org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt,
                              java.net.InetSocketAddress[] favoredNodes)
                       throws java.io.IOException

Same as

create(String, FsPermission, EnumSet, boolean, short, long,
 Progressable, int, ChecksumOpt)

with the addition of favoredNodes that is a hint to where the namenode should place the file blocks. The favored nodes hint is not persisted in HDFS. Hence it may be honored at the creation time only. HDFS could move the blocks during balancing or replication, to move the blocks from favored nodes. A value of null means no favored nodes for this create

Throws:: java.io.IOException

create

public DFSOutputStream create(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission permission,
                              java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                              boolean createParent,
                              short replication,
                              long blockSize,
                              org.apache.hadoop.util.Progressable progress,
                              int buffersize,
                              org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt,
                              java.net.InetSocketAddress[] favoredNodes,
                              java.lang.String ecPolicyName)
                       throws java.io.IOException

Same as

create(String, FsPermission, EnumSet, boolean, short, long,
 Progressable, int, ChecksumOpt, InetSocketAddress[])

with the addition of ecPolicyName that is used to specify a specific erasure coding policy instead of inheriting any policy from this new file's parent directory. This policy will be persisted in HDFS. A value of null means inheriting parent groups' whatever policy.

Throws:: java.io.IOException

create

public DFSOutputStream create(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission permission,
                              java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                              boolean createParent,
                              short replication,
                              long blockSize,
                              org.apache.hadoop.util.Progressable progress,
                              int buffersize,
                              org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt,
                              java.net.InetSocketAddress[] favoredNodes,
                              java.lang.String ecPolicyName,
                              java.lang.String storagePolicy)
                       throws java.io.IOException

Same as

create(String, FsPermission, EnumSet, boolean, short, long,
 Progressable, int, ChecksumOpt, InetSocketAddress[], String)

with the storagePolicy that is used to specify a specific storage policy instead of inheriting any policy from this new file's parent directory. This policy will be persisted in HDFS. A value of null means inheriting parent groups' whatever policy.

Throws:: java.io.IOException

primitiveCreate

public DFSOutputStream primitiveCreate(java.lang.String src,
                                       org.apache.hadoop.fs.permission.FsPermission absPermission,
                                       java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                       boolean createParent,
                                       short replication,
                                       long blockSize,
                                       org.apache.hadoop.util.Progressable progress,
                                       int buffersize,
                                       org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)
                                throws java.io.IOException

Same as {

create(String, FsPermission, EnumSet, short, long,
  Progressable, int, ChecksumOpt)

except that the permission is absolute (ie has already been masked with umask.

Throws:: java.io.IOException

createSymlink

public void createSymlink(java.lang.String target,
                          java.lang.String link,
                          boolean createParent)
                   throws java.io.IOException

Creates a symbolic link.

Throws:: java.io.IOException
See Also:: ClientProtocol.createSymlink(String, String,FsPermission, boolean)

getLinkTarget
```
public java.lang.String getLinkTarget(java.lang.String path)
                               throws java.io.IOException
```
Resolve the *first* symlink, if any, in the path.

Throws:

java.io.IOException

See Also:

ClientProtocol.getLinkTarget(String)

append

public HdfsDataOutputStream append(java.lang.String src,
                                   int buffersize,
                                   java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                   org.apache.hadoop.util.Progressable progress,
                                   org.apache.hadoop.fs.FileSystem.Statistics statistics)
                            throws java.io.IOException

Append to an existing HDFS file.

Parameters:: src - file name; buffersize - buffer size; flag - indicates whether to append data to a new block instead of the last block; progress - for reporting write-progress; null is acceptable.; statistics - file system statistics; null is acceptable.
Returns:: an output stream for writing into the file
Throws:: java.io.IOException
See Also:: ClientProtocol.append(String, String, EnumSetWritable)

append

public HdfsDataOutputStream append(java.lang.String src,
                                   int buffersize,
                                   java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                   org.apache.hadoop.util.Progressable progress,
                                   org.apache.hadoop.fs.FileSystem.Statistics statistics,
                                   java.net.InetSocketAddress[] favoredNodes)
                            throws java.io.IOException

Append to an existing HDFS file.

Parameters:: src - file name; buffersize - buffer size; flag - indicates whether to append data to a new block instead of the last block; progress - for reporting write-progress; null is acceptable.; statistics - file system statistics; null is acceptable.; favoredNodes - FavoredNodes for new blocks
Returns:: an output stream for writing into the file
Throws:: java.io.IOException
See Also:: ClientProtocol.append(String, String, EnumSetWritable)

setReplication
```
public boolean setReplication(java.lang.String src,
                              short replication)
                       throws java.io.IOException
```
Set replication for an existing file.

Parameters:

src - file name

replication - replication to set the file to

Throws:

java.io.IOException

See Also:

ClientProtocol.setReplication(String, short)

setStoragePolicy

public void setStoragePolicy(java.lang.String src,
                             java.lang.String policyName)
                      throws java.io.IOException

Set storage policy for an existing file/directory

Parameters:: src - file/directory name; policyName - name of the storage policy
Throws:: java.io.IOException

unsetStoragePolicy
```
public void unsetStoragePolicy(java.lang.String src)
                        throws java.io.IOException
```
Unset storage policy set for a given file/directory.

Parameters:

src - file/directory name

Throws:

java.io.IOException

getStoragePolicy

public BlockStoragePolicy getStoragePolicy(java.lang.String path)
                                    throws java.io.IOException

Parameters:: path - file/directory name
Returns:: Get the storage policy for specified path
Throws:: java.io.IOException

getStoragePolicies

public BlockStoragePolicy[] getStoragePolicies()
                                        throws java.io.IOException

Returns:: All the existing storage policies
Throws:: java.io.IOException

rename
```
@Deprecated
public boolean rename(java.lang.String src,
                      java.lang.String dst)
               throws java.io.IOException
```
Deprecated.
Use rename(String, String, Options.Rename...) instead.

Rename file or directory.

Throws:

java.io.IOException

See Also:

ClientProtocol.rename(String, String)

concat
```
public void concat(java.lang.String trg,
                   java.lang.String[] srcs)
            throws java.io.IOException
```
Move blocks from src to trg and delete src See ClientProtocol.concat(java.lang.String, java.lang.String[]).

Throws:

java.io.IOException

rename

public void rename(java.lang.String src,
                   java.lang.String dst,
                   org.apache.hadoop.fs.Options.Rename... options)
            throws java.io.IOException

Rename file or directory.

Throws:: java.io.IOException
See Also:: ClientProtocol.rename2(String, String, Options.Rename...)

truncate
```
public boolean truncate(java.lang.String src,
                        long newLength)
                 throws java.io.IOException
```
Truncate a file to an indicated size See ClientProtocol.truncate(java.lang.String, long, java.lang.String).

Throws:

java.io.IOException

delete
```
@Deprecated
public boolean delete(java.lang.String src)
               throws java.io.IOException
```
Deprecated.

Delete file or directory. See ClientProtocol.delete(String, boolean).

Throws:

java.io.IOException

delete
```
public boolean delete(java.lang.String src,
                      boolean recursive)
               throws java.io.IOException
```
delete file or directory. delete contents of the directory if non empty and recursive set to true

Throws:

java.io.IOException

See Also:

ClientProtocol.delete(String, boolean)

exists

public boolean exists(java.lang.String src)
               throws java.io.IOException

Implemented using getFileInfo(src)

Throws:: java.io.IOException

listPaths

public DirectoryListing listPaths(java.lang.String src,
                                  byte[] startAfter)
                           throws java.io.IOException

Get a partial listing of the indicated directory No block locations need to be fetched

Throws:: java.io.IOException

listPaths
```
public DirectoryListing listPaths(java.lang.String src,
                                  byte[] startAfter,
                                  boolean needLocation)
                           throws java.io.IOException
```
Get a partial listing of the indicated directory Recommend to use HdfsFileStatus.EMPTY_NAME as startAfter if the application wants to fetch a listing starting from the first entry in the directory

Throws:

java.io.IOException

See Also:

ClientProtocol.getListing(String, byte[], boolean)

batchedListPaths

public BatchedDirectoryListing batchedListPaths(java.lang.String[] srcs,
                                                byte[] startAfter,
                                                boolean needLocation)
                                         throws java.io.IOException

Get a batched listing for the indicated directories

Throws:: java.io.IOException
See Also:: ClientProtocol.getBatchedListing(String[], byte[], boolean)

getFileInfo
```
public HdfsFileStatus getFileInfo(java.lang.String src)
                           throws java.io.IOException
```
Get the file info for a specific file or directory.

Parameters:

src - The string representation of the path to the file

Returns:

object containing information regarding the file or null if file not found

Throws:

java.io.IOException

See Also:

for description of exceptions

getLocatedFileInfo
```
public HdfsLocatedFileStatus getLocatedFileInfo(java.lang.String src,
                                                boolean needBlockToken)
                                         throws java.io.IOException
```
Get the file info for a specific file or directory.

Parameters:

src - The string representation of the path to the file

needBlockToken - Include block tokens in LocatedBlocks. When block tokens are included, this call is a superset of getBlockLocations(String, long).

Returns:

object containing information regarding the file or null if file not found

Throws:

java.io.IOException

See Also:

open(HdfsPathHandle, int, boolean), for description of exceptions

isFileClosed

public boolean isFileClosed(java.lang.String src)
                     throws java.io.IOException

Close status of a file

Returns:: true if file is already closed
Throws:: java.io.IOException

getFileLinkInfo
```
public HdfsFileStatus getFileLinkInfo(java.lang.String src)
                               throws java.io.IOException
```
Get the file info for a specific file or directory. If src refers to a symlink then the FileStatus of the link is returned.

Parameters:

src - path to a file or directory. For description of exceptions thrown

Throws:

java.io.IOException

See Also:

ClientProtocol.getFileLinkInfo(String)

clearDataEncryptionKey

@Private
public void clearDataEncryptionKey()

newDataEncryptionKey
```
public DataEncryptionKey newDataEncryptionKey()
                                       throws java.io.IOException
```
Description copied from interface: DataEncryptionKeyFactory

Creates a new DataEncryptionKey.

Specified by:

newDataEncryptionKey in interface DataEncryptionKeyFactory

Returns:

DataEncryptionKey newly created

Throws:

java.io.IOException - for any error

getEncryptionKey

@VisibleForTesting
public DataEncryptionKey getEncryptionKey()

getFileChecksumWithCombineMode
```
public org.apache.hadoop.fs.FileChecksum getFileChecksumWithCombineMode(java.lang.String src,
                                                                        long length)
                                                                 throws java.io.IOException
```
Get the checksum of the whole file or a range of the file. Note that the range always starts from the beginning of the file. The file can be in replicated form, or striped mode. Depending on the dfs.checksum.combine.mode, checksums may or may not be comparable between different block layout forms.

Parameters:

src - The file path

length - the length of the range, i.e., the range is [0, length]

Returns:

The checksum

Throws:

java.io.IOException

See Also:

DistributedFileSystem.getFileChecksum(Path)

getFileChecksum
```
public org.apache.hadoop.fs.MD5MD5CRC32FileChecksum getFileChecksum(java.lang.String src,
                                                                    long length)
                                                             throws java.io.IOException
```
Get the checksum of the whole file or a range of the file. Note that the range always starts from the beginning of the file. The file can be in replicated form, or striped mode. It can be used to checksum and compare two replicated files, or two striped files, but not applicable for two files of different block layout forms.

Parameters:

src - The file path

length - the length of the range, i.e., the range is [0, length]

Returns:

The checksum

Throws:

java.io.IOException

See Also:

DistributedFileSystem.getFileChecksum(Path)

getBlockLocations

protected LocatedBlocks getBlockLocations(java.lang.String src,
                                          long length)
                                   throws java.io.IOException

Throws:: java.io.IOException

connectToDN

protected IOStreamPair connectToDN(DatanodeInfo dn,
                                   int timeout,
                                   org.apache.hadoop.security.token.Token<BlockTokenIdentifier> blockToken)
                            throws java.io.IOException

Throws:: java.io.IOException

inferChecksumTypeByReading
```
protected org.apache.hadoop.util.DataChecksum.Type inferChecksumTypeByReading(LocatedBlock lb,
                                                                              DatanodeInfo dn)
                                                                       throws java.io.IOException
```
Infer the checksum type for a replica by sending an OP_READ_BLOCK for the first byte of that replica. This is used for compatibility with older HDFS versions which did not include the checksum type in OpBlockChecksumResponseProto.

Parameters:

lb - the located block

dn - the connected datanode

Returns:

the inferred checksum type

Throws:

java.io.IOException - if an error occurs

setPermission
```
public void setPermission(java.lang.String src,
                          org.apache.hadoop.fs.permission.FsPermission permission)
                   throws java.io.IOException
```
Set permissions to a file or directory.

Parameters:

src - path name.

permission - permission to set to

Throws:

java.io.IOException

See Also:

ClientProtocol.setPermission(String, FsPermission)

setOwner

public void setOwner(java.lang.String src,
                     java.lang.String username,
                     java.lang.String groupname)
              throws java.io.IOException

Set file or directory owner.

Parameters:: src - path name.; username - user id.; groupname - user group.
Throws:: java.io.IOException
See Also:: ClientProtocol.setOwner(String, String, String)

getDiskStatus

public org.apache.hadoop.fs.FsStatus getDiskStatus()
                                            throws java.io.IOException

Throws:: java.io.IOException
See Also:: ClientProtocol.getStats()

getStateAtIndex

public static long getStateAtIndex(long[] states,
                                   int index)

getMissingBlocksCount
```
public long getMissingBlocksCount()
                           throws java.io.IOException
```
Returns count of blocks with no good replicas left. Normally should be zero.

Throws:

java.io.IOException

getMissingReplOneBlocksCount
```
public long getMissingReplOneBlocksCount()
                                  throws java.io.IOException
```
Returns count of blocks with replication factor 1 and have lost the only replica.

Throws:

java.io.IOException

getPendingDeletionBlocksCount

public long getPendingDeletionBlocksCount()
                                   throws java.io.IOException

Returns count of blocks pending on deletion.

Throws:: java.io.IOException

getLowRedundancyBlocksCount
```
public long getLowRedundancyBlocksCount()
                                 throws java.io.IOException
```
Returns aggregated count of blocks with less redundancy.

Throws:

java.io.IOException

getCorruptBlocksCount
```
public long getCorruptBlocksCount()
                           throws java.io.IOException
```
Returns count of blocks with at least one replica marked corrupt.

Throws:

java.io.IOException

getBytesInFutureBlocks
```
public long getBytesInFutureBlocks()
                            throws java.io.IOException
```
Returns number of bytes that reside in Blocks with future generation stamps.

Returns:

Bytes in Blocks with future generation stamps.

Throws:

java.io.IOException

listCorruptFileBlocks

public CorruptFileBlocks listCorruptFileBlocks(java.lang.String path,
                                               java.lang.String cookie)
                                        throws java.io.IOException

Returns:: a list in which each entry describes a corrupt file/block
Throws:: java.io.IOException

datanodeReport

public DatanodeInfo[] datanodeReport(HdfsConstants.DatanodeReportType type)
                              throws java.io.IOException

Throws:: java.io.IOException

getDatanodeStorageReport

public DatanodeStorageReport[] getDatanodeStorageReport(HdfsConstants.DatanodeReportType type)
                                                 throws java.io.IOException

Throws:: java.io.IOException

setSafeMode
```
public boolean setSafeMode(HdfsConstants.SafeModeAction action)
                    throws java.io.IOException
```
Enter, leave or get safe mode.

Throws:

java.io.IOException

See Also:

ClientProtocol.setSafeMode(HdfsConstants.SafeModeAction,boolean)

setSafeMode
```
public boolean setSafeMode(HdfsConstants.SafeModeAction action,
                           boolean isChecked)
                    throws java.io.IOException
```
Enter, leave or get safe mode.

Parameters:

action - One of SafeModeAction.GET, SafeModeAction.ENTER and SafeModeActiob.LEAVE

isChecked - If true, then check only active namenode's safemode status, else check first namenode's status.

Throws:

java.io.IOException

See Also:

ClientProtocol.setSafeMode(HdfsConstants.SafeModeAction, boolean)

createSnapshot
```
public java.lang.String createSnapshot(java.lang.String snapshotRoot,
                                       java.lang.String snapshotName)
                                throws java.io.IOException
```
Create one snapshot.

Parameters:

snapshotRoot - The directory where the snapshot is to be taken

snapshotName - Name of the snapshot

Returns:

the snapshot path.

Throws:

java.io.IOException

See Also:

ClientProtocol.createSnapshot(String, String)

deleteSnapshot
```
public void deleteSnapshot(java.lang.String snapshotRoot,
                           java.lang.String snapshotName)
                    throws java.io.IOException
```
Delete a snapshot of a snapshottable directory.

Parameters:

snapshotRoot - The snapshottable directory that the to-be-deleted snapshot belongs to

snapshotName - The name of the to-be-deleted snapshot

Throws:

java.io.IOException

See Also:

ClientProtocol.deleteSnapshot(String, String)

renameSnapshot
```
public void renameSnapshot(java.lang.String snapshotDir,
                           java.lang.String snapshotOldName,
                           java.lang.String snapshotNewName)
                    throws java.io.IOException
```
Rename a snapshot.

Parameters:

snapshotDir - The directory path where the snapshot was taken

snapshotOldName - Old name of the snapshot

snapshotNewName - New name of the snapshot

Throws:

java.io.IOException

See Also:

ClientProtocol.renameSnapshot(String, String, String)

getSnapshottableDirListing
```
public SnapshottableDirectoryStatus[] getSnapshottableDirListing()
                                                          throws java.io.IOException
```
Get all the current snapshottable directories.

Returns:

All the current snapshottable directories

Throws:

java.io.IOException

See Also:

ClientProtocol.getSnapshottableDirListing()

getSnapshotListing
```
public SnapshotStatus[] getSnapshotListing(java.lang.String snapshotRoot)
                                    throws java.io.IOException
```
Get listing of all the snapshots for a snapshottable directory.

Returns:

Information about all the snapshots for a snapshottable directory

Throws:

java.io.IOException - If an I/O error occurred

See Also:

ClientProtocol.getSnapshotListing(String)

allowSnapshot
```
public void allowSnapshot(java.lang.String snapshotRoot)
                   throws java.io.IOException
```
Allow snapshot on a directory.

Throws:

java.io.IOException

See Also:

ClientProtocol.allowSnapshot(String snapshotRoot)

disallowSnapshot
```
public void disallowSnapshot(java.lang.String snapshotRoot)
                      throws java.io.IOException
```
Disallow snapshot on a directory.

Throws:

java.io.IOException

See Also:

ClientProtocol.disallowSnapshot(String snapshotRoot)

getSnapshotDiffReport

public SnapshotDiffReport getSnapshotDiffReport(java.lang.String snapshotDir,
                                                java.lang.String fromSnapshot,
                                                java.lang.String toSnapshot)
                                         throws java.io.IOException

Get the difference between two snapshots, or between a snapshot and the current tree of a directory.

Throws:: java.io.IOException
See Also:: ClientProtocol.getSnapshotDiffReport(java.lang.String, java.lang.String, java.lang.String)

getSnapshotDiffReportListing

public SnapshotDiffReportListing getSnapshotDiffReportListing(java.lang.String snapshotDir,
                                                              java.lang.String fromSnapshot,
                                                              java.lang.String toSnapshot,
                                                              byte[] startPath,
                                                              int index)
                                                       throws java.io.IOException

Get the difference between two snapshots of a directory iteratively.

Throws:: java.io.IOException
See Also:: ClientProtocol.getSnapshotDiffReportListing(java.lang.String, java.lang.String, java.lang.String, byte[], int)

addCacheDirective

public long addCacheDirective(CacheDirectiveInfo info,
                              java.util.EnumSet<CacheFlag> flags)
                       throws java.io.IOException

Throws:: java.io.IOException

modifyCacheDirective

public void modifyCacheDirective(CacheDirectiveInfo info,
                                 java.util.EnumSet<CacheFlag> flags)
                          throws java.io.IOException

Throws:: java.io.IOException

removeCacheDirective

public void removeCacheDirective(long id)
                          throws java.io.IOException

Throws:: java.io.IOException

listCacheDirectives

public org.apache.hadoop.fs.RemoteIterator<CacheDirectiveEntry> listCacheDirectives(CacheDirectiveInfo filter)
                                                                             throws java.io.IOException

Throws:: java.io.IOException

addCachePool

public void addCachePool(CachePoolInfo info)
                  throws java.io.IOException

Throws:: java.io.IOException

modifyCachePool

public void modifyCachePool(CachePoolInfo info)
                     throws java.io.IOException

Throws:: java.io.IOException

removeCachePool

public void removeCachePool(java.lang.String poolName)
                     throws java.io.IOException

Throws:: java.io.IOException

listCachePools

public org.apache.hadoop.fs.RemoteIterator<CachePoolEntry> listCachePools()
                                                                   throws java.io.IOException

Throws:: java.io.IOException

refreshNodes
```
public void refreshNodes()
                  throws java.io.IOException
```
Refresh the hosts and exclude files. (Rereads them.) See ClientProtocol.refreshNodes() for more details.

Throws:

java.io.IOException

See Also:

ClientProtocol.refreshNodes()

metaSave
```
public void metaSave(java.lang.String pathname)
              throws java.io.IOException
```
Dumps DFS data structures into specified file.

Throws:

java.io.IOException

See Also:

ClientProtocol.metaSave(String)

setBalancerBandwidth
```
public void setBalancerBandwidth(long bandwidth)
                          throws java.io.IOException
```
Requests the namenode to tell all datanodes to use a new, non-persistent bandwidth value for dfs.datanode.balance.bandwidthPerSec. See ClientProtocol.setBalancerBandwidth(long) for more details.

Throws:

java.io.IOException

See Also:

ClientProtocol.setBalancerBandwidth(long)

finalizeUpgrade
```
public void finalizeUpgrade()
                     throws java.io.IOException
```
Throws:

java.io.IOException

See Also:

ClientProtocol.finalizeUpgrade()

upgradeStatus

public boolean upgradeStatus()
                      throws java.io.IOException

Throws:: java.io.IOException
See Also:: ClientProtocol.upgradeStatus()

mkdirs

@Deprecated
public boolean mkdirs(java.lang.String src)
               throws java.io.IOException

Deprecated.

Throws:: java.io.IOException

mkdirs
```
public boolean mkdirs(java.lang.String src,
                      org.apache.hadoop.fs.permission.FsPermission permission,
                      boolean createParent)
               throws java.io.IOException
```
Create a directory (or hierarchy of directories) with the given name and permission.

Parameters:

src - The path of the directory being created

permission - The permission of the directory being created. If permission == null, use FsPermission.getDirDefault().

createParent - create missing parent directory if true

Returns:

True if the operation success.

Throws:

java.io.IOException

See Also:

ClientProtocol.mkdirs(String, FsPermission, boolean)

primitiveMkdir

public boolean primitiveMkdir(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission absPermission)
                       throws java.io.IOException

Same {mkdirs(String, FsPermission, boolean) except that the permissions has already been masked against umask.

Throws:: java.io.IOException

primitiveMkdir

public boolean primitiveMkdir(java.lang.String src,
                              org.apache.hadoop.fs.permission.FsPermission absPermission,
                              boolean createParent)
                       throws java.io.IOException

Same {mkdirs(String, FsPermission, boolean) except that the permissions has already been masked against umask.

Throws:: java.io.IOException

setTimes

public void setTimes(java.lang.String src,
                     long mtime,
                     long atime)
              throws java.io.IOException

set the modification and access time of a file.

Throws:: java.io.IOException
See Also:: ClientProtocol.setTimes(String, long, long)

toString
```
public java.lang.String toString()
```
Overrides:

toString in class java.lang.Object

getDefaultReadCachingStrategy

public CachingStrategy getDefaultReadCachingStrategy()

getDefaultWriteCachingStrategy

public CachingStrategy getDefaultWriteCachingStrategy()

getClientContext

public ClientContext getClientContext()

modifyAclEntries

public void modifyAclEntries(java.lang.String src,
                             java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)
                      throws java.io.IOException

Throws:: java.io.IOException

removeAclEntries

public void removeAclEntries(java.lang.String src,
                             java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)
                      throws java.io.IOException

Throws:: java.io.IOException

removeDefaultAcl

public void removeDefaultAcl(java.lang.String src)
                      throws java.io.IOException

Throws:: java.io.IOException

removeAcl

public void removeAcl(java.lang.String src)
               throws java.io.IOException

Throws:: java.io.IOException

setAcl

public void setAcl(java.lang.String src,
                   java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)
            throws java.io.IOException

Throws:: java.io.IOException

getAclStatus

public org.apache.hadoop.fs.permission.AclStatus getAclStatus(java.lang.String src)
                                                       throws java.io.IOException

Throws:: java.io.IOException

createEncryptionZone

public void createEncryptionZone(java.lang.String src,
                                 java.lang.String keyName)
                          throws java.io.IOException

Throws:: java.io.IOException

getEZForPath

public EncryptionZone getEZForPath(java.lang.String src)
                            throws java.io.IOException

Throws:: java.io.IOException

listEncryptionZones

public org.apache.hadoop.fs.RemoteIterator<EncryptionZone> listEncryptionZones()
                                                                        throws java.io.IOException

Throws:: java.io.IOException

reencryptEncryptionZone

public void reencryptEncryptionZone(java.lang.String zone,
                                    HdfsConstants.ReencryptAction action)
                             throws java.io.IOException

Throws:: java.io.IOException

listReencryptionStatus

public org.apache.hadoop.fs.RemoteIterator<ZoneReencryptionStatus> listReencryptionStatus()
                                                                                   throws java.io.IOException

Throws:: java.io.IOException

setErasureCodingPolicy

public void setErasureCodingPolicy(java.lang.String src,
                                   java.lang.String ecPolicyName)
                            throws java.io.IOException

Throws:: java.io.IOException

unsetErasureCodingPolicy

public void unsetErasureCodingPolicy(java.lang.String src)
                              throws java.io.IOException

Throws:: java.io.IOException

getECTopologyResultForPolicies

public ECTopologyVerifierResult getECTopologyResultForPolicies(java.lang.String... policyNames)
                                                        throws java.io.IOException

Throws:: java.io.IOException

setXAttr

public void setXAttr(java.lang.String src,
                     java.lang.String name,
                     byte[] value,
                     java.util.EnumSet<org.apache.hadoop.fs.XAttrSetFlag> flag)
              throws java.io.IOException

Throws:: java.io.IOException

getXAttr

public byte[] getXAttr(java.lang.String src,
                       java.lang.String name)
                throws java.io.IOException

Throws:: java.io.IOException

getXAttrs

public java.util.Map<java.lang.String,byte[]> getXAttrs(java.lang.String src)
                                                       throws java.io.IOException

Throws:: java.io.IOException

getXAttrs

public java.util.Map<java.lang.String,byte[]> getXAttrs(java.lang.String src,
                                                              java.util.List<java.lang.String> names)
                                                       throws java.io.IOException

Throws:: java.io.IOException

listXAttrs

public java.util.List<java.lang.String> listXAttrs(java.lang.String src)
                                            throws java.io.IOException

Throws:: java.io.IOException

removeXAttr

public void removeXAttr(java.lang.String src,
                        java.lang.String name)
                 throws java.io.IOException

Throws:: java.io.IOException

checkAccess

public void checkAccess(java.lang.String src,
                        org.apache.hadoop.fs.permission.FsAction mode)
                 throws java.io.IOException

Throws:: java.io.IOException

getErasureCodingPolicies

public ErasureCodingPolicyInfo[] getErasureCodingPolicies()
                                                   throws java.io.IOException

Throws:: java.io.IOException

getErasureCodingCodecs

public java.util.Map<java.lang.String,java.lang.String> getErasureCodingCodecs()
                                                                              throws java.io.IOException

Throws:: java.io.IOException

addErasureCodingPolicies

public AddErasureCodingPolicyResponse[] addErasureCodingPolicies(ErasureCodingPolicy[] policies)
                                                          throws java.io.IOException

Throws:: java.io.IOException

removeErasureCodingPolicy

public void removeErasureCodingPolicy(java.lang.String ecPolicyName)
                               throws java.io.IOException

Throws:: java.io.IOException

enableErasureCodingPolicy

public void enableErasureCodingPolicy(java.lang.String ecPolicyName)
                               throws java.io.IOException

Throws:: java.io.IOException

disableErasureCodingPolicy

public void disableErasureCodingPolicy(java.lang.String ecPolicyName)
                                throws java.io.IOException

Throws:: java.io.IOException

getInotifyEventStream

public DFSInotifyEventInputStream getInotifyEventStream()
                                                 throws java.io.IOException

Throws:: java.io.IOException

getInotifyEventStream

public DFSInotifyEventInputStream getInotifyEventStream(long lastReadTxid)
                                                 throws java.io.IOException

Throws:: java.io.IOException

newConnectedPeer
```
public Peer newConnectedPeer(java.net.InetSocketAddress addr,
                             org.apache.hadoop.security.token.Token<BlockTokenIdentifier> blockToken,
                             DatanodeID datanodeId)
                      throws java.io.IOException
```
Specified by:

newConnectedPeer in interface RemotePeerFactory

Parameters:

addr - The address to connect to.

blockToken - Token used during optional SASL negotiation

datanodeId - ID of destination DataNode

Returns:

A new Peer connected to the address.

Throws:

java.io.IOException - If there was an error connecting or creating the remote socket, encrypted stream, etc.

getKeyProviderUri
```
public java.net.URI getKeyProviderUri()
                               throws java.io.IOException
```
Specified by:

getKeyProviderUri in interface org.apache.hadoop.crypto.key.KeyProviderTokenIssuer

Throws:

java.io.IOException

getKeyProvider

public org.apache.hadoop.crypto.key.KeyProvider getKeyProvider()
                                                        throws java.io.IOException

Specified by:: getKeyProvider in interface org.apache.hadoop.crypto.key.KeyProviderTokenIssuer
Throws:: java.io.IOException

setKeyProvider

@VisibleForTesting
public void setKeyProvider(org.apache.hadoop.crypto.key.KeyProvider provider)

getSaslDataTransferClient
```
public SaslDataTransferClient getSaslDataTransferClient()
```
Returns the SaslDataTransferClient configured for this DFSClient.

Returns:

SaslDataTransferClient configured for this DFSClient

getErasureCodingPolicy
```
public ErasureCodingPolicy getErasureCodingPolicy(java.lang.String src)
                                           throws java.io.IOException
```
Get the erasure coding policy information for the specified path

Parameters:

src - path to get the information for

Returns:

Returns the policy information if file or directory on the path is erasure coded, null otherwise. Null will be returned if directory or file has REPLICATION policy.

Throws:

java.io.IOException

satisfyStoragePolicy
```
public void satisfyStoragePolicy(java.lang.String src)
                          throws java.io.IOException
```
Satisfy storage policy for an existing file/directory.

Parameters:

src - file/directory name

Throws:

java.io.IOException

listOpenFiles

@Deprecated
public org.apache.hadoop.fs.RemoteIterator<OpenFileEntry> listOpenFiles()
                                                                 throws java.io.IOException

Deprecated.

Get a remote iterator to the open files list managed by NameNode.

Throws:: java.io.IOException

listOpenFiles

public org.apache.hadoop.fs.RemoteIterator<OpenFileEntry> listOpenFiles(java.lang.String path)
                                                                 throws java.io.IOException

Get a remote iterator to the open files list by path, managed by NameNode.

Parameters:: path -
Throws:: java.io.IOException

listOpenFiles

public org.apache.hadoop.fs.RemoteIterator<OpenFileEntry> listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes)
                                                                 throws java.io.IOException

Get a remote iterator to the open files list by type, managed by NameNode.

Parameters:: openFilesTypes -
Throws:: java.io.IOException

listOpenFiles

public org.apache.hadoop.fs.RemoteIterator<OpenFileEntry> listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes,
                                                                        java.lang.String path)
                                                                 throws java.io.IOException

Get a remote iterator to the open files list by type and path, managed by NameNode.

Parameters:: openFilesTypes -; path -
Throws:: java.io.IOException

msync
```
public void msync()
           throws java.io.IOException
```
A blocking call to wait for Observer NameNode state ID to reach to the current client state ID. Current client state ID is given by the client alignment context. An assumption is that client alignment context has the state ID set at this point. This is become ObserverReadProxyProvider sets up the initial state ID when it is being created.

Throws:

java.io.IOException

getHAServiceState

@VisibleForTesting
public org.apache.hadoop.ha.HAServiceProtocol.HAServiceState getHAServiceState()
                                                                        throws java.io.IOException

An unblocking call to get the HA service state of NameNode.

Returns:: HA state of NameNode
Throws:: java.io.IOException

getDeadNodes
```
public java.util.concurrent.ConcurrentHashMap<DatanodeInfo,DatanodeInfo> getDeadNodes(DFSInputStream dfsInputStream)
```
If deadNodeDetectionEnabled is true, return the dead nodes that detected by all the DFSInputStreams in the same client. Otherwise return the dead nodes that detected by given DFSInputStream.

isDeadNode
```
public boolean isDeadNode(DFSInputStream dfsInputStream,
                          DatanodeInfo datanodeInfo)
```
If deadNodeDetectionEnabled is true, judgement based on whether this datanode is included or not in DeadNodeDetector. Otherwise judgment based given DFSInputStream.

addNodeToDeadNodeDetector

public void addNodeToDeadNodeDetector(DFSInputStream dfsInputStream,
                                      DatanodeInfo datanodeInfo)

Add given datanode in DeadNodeDetector.

removeNodeFromDeadNodeDetector

public void removeNodeFromDeadNodeDetector(DFSInputStream dfsInputStream,
                                           DatanodeInfo datanodeInfo)

Remove given datanode from DeadNodeDetector.

removeNodeFromDeadNodeDetector

public void removeNodeFromDeadNodeDetector(DFSInputStream dfsInputStream,
                                           LocatedBlocks locatedBlocks)

Remove datanodes that given block placed on from DeadNodeDetector.

getDeadNodeDetector
```
public DeadNodeDetector getDeadNodeDetector()
```
Obtain DeadNodeDetector of the current client.

getLocatedBlockRefresher
```
public LocatedBlocksRefresher getLocatedBlockRefresher()
```
Obtain LocatedBlocksRefresher of the current client.

addLocatedBlocksRefresh
```
public void addLocatedBlocksRefresh(DFSInputStream dfsInputStream)
```
Adds the DFSInputStream to the LocatedBlocksRefresher, so that the underlying LocatedBlocks is periodically refreshed.

removeLocatedBlocksRefresh
```
public void removeLocatedBlocksRefresh(DFSInputStream dfsInputStream)
```
Removes the DFSInputStream from the LocatedBlocksRefresher, so that the underlying LocatedBlocks is no longer periodically refreshed.

Parameters:

dfsInputStream -

slowDatanodeReport

public DatanodeInfo[] slowDatanodeReport()
                                  throws java.io.IOException

Throws:: java.io.IOException

getEnclosingRoot

public org.apache.hadoop.fs.Path getEnclosingRoot(java.lang.String src)
                                           throws java.io.IOException

Throws:: java.io.IOException

Class DFSClient

Nested Class Summary

Field Summary

Fields inherited from interface org.apache.hadoop.security.token.DelegationTokenIssuer

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.hadoop.security.token.DelegationTokenIssuer

Field Detail

LOG

Constructor Detail

DFSClient

DFSClient

DFSClient

DFSClient

DFSClient

Method Detail

setDisabledStopDeadNodeDetectorThreadForTest

getConf

getClientName

getLeaseRenewer

putFileBeingWritten

removeFileBeingWritten

isFilesBeingWrittenEmpty

isClientRunning

getNumOfFilesBeingWritten

renewLease

closeAllFilesBeingWritten

close

closeOutputStreams

getBlockSize

getServerDefaults

getCanonicalServiceName

getDelegationToken

getDelegationToken

renewDelegationToken

cancelDelegationToken

reportBadBlocks

getRefreshReadBlkLocationsInterval

getLocatedBlocks

getLocatedBlocks

getBlockLocations

createWrappedInputStream

createWrappedOutputStream

createWrappedOutputStream

open

open

open

open

getNamenode

create

create

create

create

create

create

create

create

create

create

primitiveCreate

createSymlink

getLinkTarget

append

append

setReplication

setStoragePolicy

unsetStoragePolicy

getStoragePolicy

getStoragePolicies

rename

concat

rename

truncate

delete

delete

exists

listPaths

listPaths

batchedListPaths