DistributedFileSystem (Apache Hadoop HDFS Client 3.4.1.100-eep-941 API)

java.lang.Object
- org.apache.hadoop.conf.Configured
- - org.apache.hadoop.fs.FileSystem
  - - org.apache.hadoop.hdfs.DistributedFileSystem

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, org.apache.hadoop.conf.Configurable, org.apache.hadoop.crypto.key.KeyProviderTokenIssuer, org.apache.hadoop.fs.BatchListingOperations, org.apache.hadoop.fs.BulkDeleteSource, org.apache.hadoop.fs.LeaseRecoverable, org.apache.hadoop.fs.PathCapabilities, org.apache.hadoop.fs.SafeMode, org.apache.hadoop.security.token.DelegationTokenIssuer

Direct Known Subclasses:

ViewDistributedFileSystem
```
@LimitedPrivate({"MapReduce","HBase"})
@Unstable
public class DistributedFileSystem
extends org.apache.hadoop.fs.FileSystem
implements org.apache.hadoop.crypto.key.KeyProviderTokenIssuer, org.apache.hadoop.fs.BatchListingOperations, org.apache.hadoop.fs.LeaseRecoverable, org.apache.hadoop.fs.SafeMode
```
Implementation of the abstract FileSystem for the DFS system. This object is the way end-user code interacts with a Hadoop DistributedFileSystem.

Nested Class Summary

Nested Classes
Modifier and Type	Class	Description
`static class`	`DistributedFileSystem.HdfsDataOutputStreamBuilder`	HdfsDataOutputStreamBuilder provides the HDFS-specific capabilities to write file on HDFS.

Nested classes/interfaces inherited from class org.apache.hadoop.fs.FileSystem
org.apache.hadoop.fs.FileSystem.DirectoryEntries, org.apache.hadoop.fs.FileSystem.Statistics

Field Summary
- Fields inherited from class org.apache.hadoop.fs.FileSystem
  DEFAULT_FS, FS_DEFAULT_NAME_KEY, LOG, SHUTDOWN_HOOK_PRIORITY, statistics, TRASH_PREFIX, USER_HOME_PREFIX
- Fields inherited from interface org.apache.hadoop.security.token.DelegationTokenIssuer
  TOKEN_LOG

Constructor Summary

Constructors
Constructor Description

DistributedFileSystem()

Constructors
Constructor	Description
`DistributedFileSystem()`

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`void`	`access(org.apache.hadoop.fs.Path path, org.apache.hadoop.fs.permission.FsAction mode)`
`long`	`addCacheDirective(CacheDirectiveInfo info)`
`long`	`addCacheDirective(CacheDirectiveInfo info, java.util.EnumSet<CacheFlag> flags)`	Add a new CacheDirective.
`void`	`addCachePool(CachePoolInfo info)`	Add a cache pool.
`AddErasureCodingPolicyResponse[]`	`addErasureCodingPolicies(ErasureCodingPolicy[] policies)`	Add Erasure coding policies to HDFS.
`void`	`allowSnapshot(org.apache.hadoop.fs.Path path)`
`org.apache.hadoop.fs.FSDataOutputStream`	`append(org.apache.hadoop.fs.Path f, int bufferSize, org.apache.hadoop.util.Progressable progress)`
`org.apache.hadoop.fs.FSDataOutputStream`	`append(org.apache.hadoop.fs.Path f, int bufferSize, org.apache.hadoop.util.Progressable progress, boolean appendToNewBlock)`
`org.apache.hadoop.fs.FSDataOutputStream`	`append(org.apache.hadoop.fs.Path f, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, int bufferSize, org.apache.hadoop.util.Progressable progress)`	Append to an existing file (optional operation).
`org.apache.hadoop.fs.FSDataOutputStream`	`append(org.apache.hadoop.fs.Path f, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, int bufferSize, org.apache.hadoop.util.Progressable progress, java.net.InetSocketAddress[] favoredNodes)`	Append to an existing file (optional operation).
`DistributedFileSystem.HdfsDataOutputStreamBuilder`	`appendFile(org.apache.hadoop.fs.Path path)`	Create a `DistributedFileSystem.HdfsDataOutputStreamBuilder` to append a file on DFS.
`org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.PartialListing<org.apache.hadoop.fs.LocatedFileStatus>>`	`batchedListLocatedStatusIterator(java.util.List<org.apache.hadoop.fs.Path> paths)`
`org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.PartialListing<org.apache.hadoop.fs.FileStatus>>`	`batchedListStatusIterator(java.util.List<org.apache.hadoop.fs.Path> paths)`
`protected java.net.URI`	`canonicalizeUri(java.net.URI uri)`
`void`	`close()`
`void`	`concat(org.apache.hadoop.fs.Path trg, org.apache.hadoop.fs.Path[] psrcs)`	Move blocks from srcs to trg and delete srcs afterwards.
`org.apache.hadoop.fs.FSDataOutputStream`	`create(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission permission, boolean overwrite, int bufferSize, short replication, long blockSize, org.apache.hadoop.util.Progressable progress)`
`HdfsDataOutputStream`	`create(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission permission, boolean overwrite, int bufferSize, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, java.net.InetSocketAddress[] favoredNodes)`	Same as `create(Path, FsPermission, boolean, int, short, long, Progressable)` with the addition of favoredNodes that is a hint to where the namenode should place the file blocks.
`org.apache.hadoop.fs.FSDataOutputStream`	`create(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> cflags, int bufferSize, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)`
`void`	`createEncryptionZone(org.apache.hadoop.fs.Path path, java.lang.String keyName)`
`DistributedFileSystem.HdfsDataOutputStreamBuilder`	`createFile(org.apache.hadoop.fs.Path path)`	Create a HdfsDataOutputStreamBuilder to create a file on DFS.
`org.apache.hadoop.fs.MultipartUploaderBuilder`	`createMultipartUploader(org.apache.hadoop.fs.Path basePath)`
`org.apache.hadoop.fs.FSDataOutputStream`	`createNonRecursive(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission permission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, int bufferSize, short replication, long blockSize, org.apache.hadoop.util.Progressable progress)`	Same as create(), except fails if parent directory doesn't already exist.
`protected HdfsPathHandle`	`createPathHandle(org.apache.hadoop.fs.FileStatus st, org.apache.hadoop.fs.Options.HandleOpt... opts)`	Create a handle to an HDFS file.
`org.apache.hadoop.fs.Path`	`createSnapshot(org.apache.hadoop.fs.Path path, java.lang.String snapshotName)`
`void`	`createSymlink(org.apache.hadoop.fs.Path target, org.apache.hadoop.fs.Path link, boolean createParent)`
`boolean`	`delete(org.apache.hadoop.fs.Path f, boolean recursive)`
`void`	`deleteSnapshot(org.apache.hadoop.fs.Path snapshotDir, java.lang.String snapshotName)`
`void`	`disableErasureCodingPolicy(java.lang.String ecPolicyName)`	Disable erasure coding policy.
`void`	`disallowSnapshot(org.apache.hadoop.fs.Path path)`
`void`	`enableErasureCodingPolicy(java.lang.String ecPolicyName)`	Enable erasure coding policy.
`void`	`finalizeUpgrade()`	Finalize previously upgraded files system state.
`protected org.apache.hadoop.fs.Path`	`fixRelativePart(org.apache.hadoop.fs.Path p)`
`org.apache.hadoop.fs.permission.AclStatus`	`getAclStatus(org.apache.hadoop.fs.Path path)`
`org.apache.hadoop.security.token.DelegationTokenIssuer[]`	`getAdditionalTokenIssuers()`
`java.util.Map<java.lang.String,java.lang.String>`	`getAllErasureCodingCodecs()`	Retrieve all the erasure coding codecs and coders supported by this file system.
`java.util.Collection<ErasureCodingPolicyInfo>`	`getAllErasureCodingPolicies()`	Retrieve all the erasure coding policies supported by this file system, including enabled, disabled and removed policies, but excluding REPLICATION policy.
`java.util.Collection<BlockStoragePolicy>`	`getAllStoragePolicies()`
`long`	`getBytesWithFutureGenerationStamps()`	Returns number of bytes within blocks with future generation stamp.
`java.lang.String`	`getCanonicalServiceName()`	Get a canonical service name for this file system.
`DFSClient`	`getClient()`
`org.apache.hadoop.fs.ContentSummary`	`getContentSummary(org.apache.hadoop.fs.Path f)`
`long`	`getCorruptBlocksCount()`	Returns count of blocks with at least one replica marked corrupt.
`DatanodeInfo[]`	`getDataNodeStats()`
`DatanodeInfo[]`	`getDataNodeStats(HdfsConstants.DatanodeReportType type)`
`long`	`getDefaultBlockSize()`
`protected int`	`getDefaultPort()`
`short`	`getDefaultReplication()`
`org.apache.hadoop.security.token.Token<DelegationTokenIdentifier>`	`getDelegationToken(java.lang.String renewer)`
`ECTopologyVerifierResult`	`getECTopologyResultForPolicies(java.lang.String... policyNames)`	Verifies if the given policies are supported in the given cluster setup.
`org.apache.hadoop.fs.Path`	`getEnclosingRoot(org.apache.hadoop.fs.Path path)`	Return path of the enclosing root for a given path The enclosing root path is a common ancestor that should be used for temp and staging dirs as well as within encryption zones and other restricted directories.
`ErasureCodingPolicy`	`getErasureCodingPolicy(org.apache.hadoop.fs.Path path)`	Get erasure coding policy information for the specified path.
`EncryptionZone`	`getEZForPath(org.apache.hadoop.fs.Path path)`
`org.apache.hadoop.fs.BlockLocation[]`	`getFileBlockLocations(org.apache.hadoop.fs.FileStatus file, long start, long len)`
`org.apache.hadoop.fs.BlockLocation[]`	`getFileBlockLocations(org.apache.hadoop.fs.Path p, long start, long len)`	The returned BlockLocation will have different formats for replicated and erasure coded file.
`org.apache.hadoop.fs.FileChecksum`	`getFileChecksum(org.apache.hadoop.fs.Path f)`
`org.apache.hadoop.fs.FileChecksum`	`getFileChecksum(org.apache.hadoop.fs.Path f, long length)`
`org.apache.hadoop.fs.FileEncryptionInfo`	`getFileEncryptionInfo(org.apache.hadoop.fs.Path path)`
`org.apache.hadoop.fs.FileStatus`	`getFileLinkStatus(org.apache.hadoop.fs.Path f)`
`org.apache.hadoop.fs.FileStatus`	`getFileStatus(org.apache.hadoop.fs.Path f)`	Returns the stat information about the file.
`DFSHedgedReadMetrics`	`getHedgedReadMetrics()`	Returns the hedged read metrics object for this client.
`org.apache.hadoop.fs.Path`	`getHomeDirectory()`
`DFSInotifyEventInputStream`	`getInotifyEventStream()`
`DFSInotifyEventInputStream`	`getInotifyEventStream(long lastReadTxid)`
`org.apache.hadoop.crypto.key.KeyProvider`	`getKeyProvider()`
`java.net.URI`	`getKeyProviderUri()`
`org.apache.hadoop.fs.Path`	`getLinkTarget(org.apache.hadoop.fs.Path f)`
`LocatedBlocks`	`getLocatedBlocks(org.apache.hadoop.fs.Path p, long start, long len)`	Returns LocatedBlocks of the corresponding HDFS file p from offset start for length len.
`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.
`long`	`getPendingDeletionBlocksCount()`	Returns count of blocks pending on deletion.
`org.apache.hadoop.fs.QuotaUsage`	`getQuotaUsage(org.apache.hadoop.fs.Path f)`
`java.lang.String`	`getScheme()`	Return the protocol scheme for the FileSystem.
`org.apache.hadoop.fs.FsServerDefaults`	`getServerDefaults()`
`DatanodeInfo[]`	`getSlowDatanodeStats()`	Retrieve stats for slow running datanodes.
`SnapshotDiffReport`	`getSnapshotDiffReport(org.apache.hadoop.fs.Path 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(org.apache.hadoop.fs.Path snapshotDir, java.lang.String fromSnapshotName, java.lang.String toSnapshotName, java.lang.String snapshotDiffStartPath, int snapshotDiffIndex)`	Get the difference between two snapshots of a directory iteratively.
`SnapshotStatus[]`	`getSnapshotListing(org.apache.hadoop.fs.Path snapshotRoot)`
`SnapshottableDirectoryStatus[]`	`getSnapshottableDirListing()`	Get the list of snapshottable directories that are owned by the current user.
`org.apache.hadoop.fs.FsStatus`	`getStatus(org.apache.hadoop.fs.Path p)`
`BlockStoragePolicy[]`	`getStoragePolicies()`	Deprecated.
`org.apache.hadoop.fs.BlockStoragePolicySpi`	`getStoragePolicy(org.apache.hadoop.fs.Path path)`
`org.apache.hadoop.fs.Path`	`getTrashRoot(org.apache.hadoop.fs.Path path)`	Get the root directory of Trash for a path in HDFS.
`java.util.Collection<org.apache.hadoop.fs.FileStatus>`	`getTrashRoots(boolean allUsers)`	Get all the trash roots of HDFS for current user or for all the users.
`java.net.URI`	`getUri()`
`org.apache.hadoop.fs.Path`	`getWorkingDirectory()`
`byte[]`	`getXAttr(org.apache.hadoop.fs.Path path, java.lang.String name)`
`java.util.Map<java.lang.String,byte[]>`	`getXAttrs(org.apache.hadoop.fs.Path path)`
`java.util.Map<java.lang.String,byte[]>`	`getXAttrs(org.apache.hadoop.fs.Path path, java.util.List<java.lang.String> names)`
`boolean`	`hasPathCapability(org.apache.hadoop.fs.Path path, java.lang.String capability)`	HDFS client capabilities.
`void`	`initialize(java.net.URI uri, org.apache.hadoop.conf.Configuration conf)`
`boolean`	`isFileClosed(org.apache.hadoop.fs.Path src)`	Get the close status of a file
`boolean`	`isInSafeMode()`	Utility function that returns if the NameNode is in safemode or not.
`boolean`	`isSnapshotTrashRootEnabled()`	HDFS only.
`org.apache.hadoop.fs.RemoteIterator<CacheDirectiveEntry>`	`listCacheDirectives(CacheDirectiveInfo filter)`	List cache directives.
`org.apache.hadoop.fs.RemoteIterator<CachePoolEntry>`	`listCachePools()`	List all cache pools.
`org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.Path>`	`listCorruptFileBlocks(org.apache.hadoop.fs.Path path)`
`org.apache.hadoop.fs.RemoteIterator<EncryptionZone>`	`listEncryptionZones()`
`protected org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.LocatedFileStatus>`	`listLocatedStatus(org.apache.hadoop.fs.Path p, org.apache.hadoop.fs.PathFilter filter)`	The BlockLocation of returned LocatedFileStatus will have different formats for replicated and erasure coded file.
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles()`	Deprecated.
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes)`	Deprecated.
`org.apache.hadoop.fs.RemoteIterator<OpenFileEntry>`	`listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes, java.lang.String path)`
`org.apache.hadoop.fs.RemoteIterator<ZoneReencryptionStatus>`	`listReencryptionStatus()`
`org.apache.hadoop.fs.FileStatus[]`	`listStatus(org.apache.hadoop.fs.Path p)`	List all the entries of a directory Note that this operation is not atomic for a large directory.
`org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.FileStatus>`	`listStatusIterator(org.apache.hadoop.fs.Path p)`	Returns a remote iterator so that followup calls are made on demand while consuming the entries.
`java.util.List<java.lang.String>`	`listXAttrs(org.apache.hadoop.fs.Path path)`
`void`	`metaSave(java.lang.String pathname)`
`boolean`	`mkdir(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission permission)`	Create a directory, only when the parent directories exist.
`boolean`	`mkdirs(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission permission)`	Create a directory and its parent directories.
`void`	`modifyAclEntries(org.apache.hadoop.fs.Path path, java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)`
`void`	`modifyCacheDirective(CacheDirectiveInfo info)`
`void`	`modifyCacheDirective(CacheDirectiveInfo info, java.util.EnumSet<CacheFlag> flags)`	Modify a CacheDirective.
`void`	`modifyCachePool(CachePoolInfo info)`	Modify an existing cache pool.
`void`	`msync()`	Synchronize client metadata state with Active NameNode.
`org.apache.hadoop.fs.FSDataInputStream`	`open(org.apache.hadoop.fs.PathHandle fd, int bufferSize)`	Opens an FSDataInputStream with the indicated file ID extracted from the `PathHandle`.
`org.apache.hadoop.fs.FSDataInputStream`	`open(org.apache.hadoop.fs.Path f, int bufferSize)`
`protected HdfsDataOutputStream`	`primitiveCreate(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission absolutePermission, java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag, int bufferSize, short replication, long blockSize, org.apache.hadoop.util.Progressable progress, org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)`
`protected boolean`	`primitiveMkdir(org.apache.hadoop.fs.Path f, org.apache.hadoop.fs.permission.FsPermission absolutePermission)`
`void`	`provisionEZTrash(org.apache.hadoop.fs.Path path, org.apache.hadoop.fs.permission.FsPermission trashPermission)`
`org.apache.hadoop.fs.Path`	`provisionSnapshotTrash(org.apache.hadoop.fs.Path path, org.apache.hadoop.fs.permission.FsPermission trashPermission)`	HDFS only.
`boolean`	`recoverLease(org.apache.hadoop.fs.Path f)`	Start the lease recovery of a file
`void`	`reencryptEncryptionZone(org.apache.hadoop.fs.Path zone, HdfsConstants.ReencryptAction action)`
`void`	`refreshNodes()`	Refreshes the list of hosts and excluded hosts from the configured files.
`void`	`removeAcl(org.apache.hadoop.fs.Path path)`
`void`	`removeAclEntries(org.apache.hadoop.fs.Path path, java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)`
`void`	`removeCacheDirective(long id)`	Remove a CacheDirectiveInfo.
`void`	`removeCachePool(java.lang.String poolName)`	Remove a cache pool.
`void`	`removeDefaultAcl(org.apache.hadoop.fs.Path path)`
`void`	`removeErasureCodingPolicy(java.lang.String ecPolicyName)`	Remove erasure coding policy.
`void`	`removeXAttr(org.apache.hadoop.fs.Path path, java.lang.String name)`
`boolean`	`rename(org.apache.hadoop.fs.Path src, org.apache.hadoop.fs.Path dst)`
`void`	`rename(org.apache.hadoop.fs.Path src, org.apache.hadoop.fs.Path dst, org.apache.hadoop.fs.Options.Rename... options)`	This rename operation is guaranteed to be atomic.
`void`	`renameSnapshot(org.apache.hadoop.fs.Path path, java.lang.String snapshotOldName, java.lang.String snapshotNewName)`
`protected org.apache.hadoop.fs.Path`	`resolveLink(org.apache.hadoop.fs.Path f)`
`boolean`	`restoreFailedStorage(java.lang.String arg)`	enable/disable/check restoreFaileStorage.
`long`	`rollEdits()`	Rolls the edit log on the active NameNode.
`RollingUpgradeInfo`	`rollingUpgrade(HdfsConstants.RollingUpgradeAction action)`	Rolling upgrade: prepare/finalize/query.
`void`	`satisfyStoragePolicy(org.apache.hadoop.fs.Path path)`	Set the source path to satisfy storage policy.
`void`	`saveNamespace()`	Save namespace image.
`boolean`	`saveNamespace(long timeWindow, long txGap)`	Save namespace image.
`void`	`setAcl(org.apache.hadoop.fs.Path path, 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.
`void`	`setErasureCodingPolicy(org.apache.hadoop.fs.Path path, java.lang.String ecPolicyName)`	Set the source path to the specified erasure coding policy.
`void`	`setOwner(org.apache.hadoop.fs.Path p, java.lang.String username, java.lang.String groupname)`
`void`	`setPermission(org.apache.hadoop.fs.Path p, org.apache.hadoop.fs.permission.FsPermission permission)`
`void`	`setQuota(org.apache.hadoop.fs.Path src, long namespaceQuota, long storagespaceQuota)`	Set a directory's quotas
`void`	`setQuotaByStorageType(org.apache.hadoop.fs.Path src, org.apache.hadoop.fs.StorageType type, long quota)`	Set the per type storage quota of a directory.
`boolean`	`setReplication(org.apache.hadoop.fs.Path src, short replication)`
`boolean`	`setSafeMode(org.apache.hadoop.fs.SafeModeAction action)`	Enter, leave or get safe mode.
`boolean`	`setSafeMode(org.apache.hadoop.fs.SafeModeAction action, boolean isChecked)`	Enter, leave or get safe mode.
`boolean`	`setSafeMode(HdfsConstants.SafeModeAction action)`	Deprecated. please instead use `setSafeMode(SafeModeAction)`.
`boolean`	`setSafeMode(HdfsConstants.SafeModeAction action, boolean isChecked)`	Deprecated. please instead use `setSafeMode(SafeModeAction, boolean)`.
`void`	`setStoragePolicy(org.apache.hadoop.fs.Path src, java.lang.String policyName)`	Set the source path to the specified storage policy.
`void`	`setTimes(org.apache.hadoop.fs.Path p, long mtime, long atime)`
`void`	`setVerifyChecksum(boolean verifyChecksum)`
`void`	`setWorkingDirectory(org.apache.hadoop.fs.Path dir)`
`void`	`setXAttr(org.apache.hadoop.fs.Path path, java.lang.String name, byte[] value, java.util.EnumSet<org.apache.hadoop.fs.XAttrSetFlag> flag)`
`org.apache.hadoop.fs.RemoteIterator<SnapshotDiffReportListing>`	`snapshotDiffReportListingRemoteIterator(org.apache.hadoop.fs.Path snapshotDir, java.lang.String fromSnapshot, java.lang.String toSnapshot)`	Returns a remote iterator so that followup calls are made on demand while consuming the SnapshotDiffReportListing entries.
`boolean`	`supportsSymlinks()`
`java.lang.String`	`toString()`
`boolean`	`truncate(org.apache.hadoop.fs.Path f, long newLength)`
`void`	`unsetErasureCodingPolicy(org.apache.hadoop.fs.Path path)`	Unset the erasure coding policy from the source path.
`void`	`unsetStoragePolicy(org.apache.hadoop.fs.Path src)`
`boolean`	`upgradeStatus()`	Get status of upgrade - finalized or not.

Methods inherited from class org.apache.hadoop.fs.FileSystem
append, append, append, areSymlinksEnabled, cancelDeleteOnExit, checkPath, clearStatistics, closeAll, closeAllForUGI, completeLocalOutput, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyToLocalFile, copyToLocalFile, copyToLocalFile, create, create, create, create, create, create, create, create, create, create, create, createBulkDelete, createDataInputStreamBuilder, createDataInputStreamBuilder, createDataOutputStreamBuilder, createFid, createNewFile, createNonRecursive, createNonRecursive, createPathId, createSnapshot, delete, deleteFid, deleteOnExit, enableSymlinks, exists, get, get, get, getAllStatistics, getBlockSize, getCanonicalUri, getChildFileSystems, getDefaultBlockSize, getDefaultReplication, getDefaultUri, getFileSystemClass, getFSofPath, getGlobalStorageStatistics, getInitialWorkingDirectory, getJobTrackerAddrs, getLength, getLocal, getName, getNamed, getPathHandle, getReplication, getServerDefaults, getStatistics, getStatistics, getStatus, getStorageStatistics, getUsed, getUsed, getZkConnectString, globStatus, globStatus, isDirectory, isFile, listFiles, listLocatedStatus, listStatus, listStatus, listStatus, listStatusBatch, makeQualified, mkdirs, mkdirs, mkdirsFid, mkdirsFid, moveFromLocalFile, moveFromLocalFile, moveToLocalFile, newInstance, newInstance, newInstance, newInstanceLocal, open, open, openFid, openFid, openFid2, openFile, openFile, openFileWithOptions, openFileWithOptions, primitiveMkdir, printStatistics, processDeleteOnExit, resolvePath, setDefaultUri, setDefaultUri, setOwnerFid, setWriteChecksum, setXAttr, startLocalOutput

Methods inherited from class org.apache.hadoop.conf.Configured
getConf, setConf

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

- Constructor Detail
  - DistributedFileSystem
```
public DistributedFileSystem()
```
- Method Detail
  - getScheme
```
public java.lang.String getScheme()
```
    Return the protocol scheme for the FileSystem.
    
    Overrides:
    
    getScheme in class org.apache.hadoop.fs.FileSystem
    
    Returns:
    
    hdfs
  - getUri
```
public java.net.URI getUri()
```
    Specified by:
    
    getUri in class org.apache.hadoop.fs.FileSystem
  - initialize
```
public void initialize(java.net.URI uri,
                       org.apache.hadoop.conf.Configuration conf)
                throws java.io.IOException
```
    Overrides:
    
    initialize in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getWorkingDirectory
```
public org.apache.hadoop.fs.Path getWorkingDirectory()
```
    Specified by:
    
    getWorkingDirectory in class org.apache.hadoop.fs.FileSystem
  - getDefaultBlockSize
```
public long getDefaultBlockSize()
```
    Overrides:
    
    getDefaultBlockSize in class org.apache.hadoop.fs.FileSystem
  - getDefaultReplication
```
public short getDefaultReplication()
```
    Overrides:
    
    getDefaultReplication in class org.apache.hadoop.fs.FileSystem
  - setWorkingDirectory
```
public void setWorkingDirectory(org.apache.hadoop.fs.Path dir)
```
    Specified by:
    
    setWorkingDirectory in class org.apache.hadoop.fs.FileSystem
  - getHomeDirectory
```
public org.apache.hadoop.fs.Path getHomeDirectory()
```
    Overrides:
    
    getHomeDirectory in class org.apache.hadoop.fs.FileSystem
  - getHedgedReadMetrics
```
public DFSHedgedReadMetrics getHedgedReadMetrics()
```
    Returns the hedged read metrics object for this client.
    
    Returns:
    
    object of DFSHedgedReadMetrics
  - getFileBlockLocations
```
public org.apache.hadoop.fs.BlockLocation[] getFileBlockLocations(org.apache.hadoop.fs.FileStatus file,
                                                                  long start,
                                                                  long len)
                                                           throws java.io.IOException
```
    Overrides:
    
    getFileBlockLocations in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getFileBlockLocations
```
public org.apache.hadoop.fs.BlockLocation[] getFileBlockLocations(org.apache.hadoop.fs.Path p,
                                                                  long start,
                                                                  long len)
                                                           throws java.io.IOException
```
    The returned BlockLocation will have different formats for replicated and erasure coded file. Please refer to FileSystem.getFileBlockLocations(FileStatus, long, long) for more details.
    
    Overrides:
    
    getFileBlockLocations in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setVerifyChecksum
```
public void setVerifyChecksum(boolean verifyChecksum)
```
    Overrides:
    
    setVerifyChecksum in class org.apache.hadoop.fs.FileSystem
  - recoverLease
```
public boolean recoverLease(org.apache.hadoop.fs.Path f)
                     throws java.io.IOException
```
    Start the lease recovery of a file
    
    Specified by:
    
    recoverLease in interface org.apache.hadoop.fs.LeaseRecoverable
    
    Parameters:
    
    f - a file
    
    Returns:
    
    true if the file is already closed
    
    Throws:
    
    java.io.IOException - if an error occurs
  - open
```
public org.apache.hadoop.fs.FSDataInputStream open(org.apache.hadoop.fs.Path f,
                                                   int bufferSize)
                                            throws java.io.IOException
```
    Specified by:
    
    open in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - open
```
public org.apache.hadoop.fs.FSDataInputStream open(org.apache.hadoop.fs.PathHandle fd,
                                                   int bufferSize)
                                            throws java.io.IOException
```
    Opens an FSDataInputStream with the indicated file ID extracted from the PathHandle.
    
    Overrides:
    
    open in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    fd - Reference to entity in this FileSystem.
    
    bufferSize - the size of the buffer to be used.
    
    Throws:
    
    org.apache.hadoop.fs.InvalidPathHandleException - If PathHandle constraints do not hold
    
    java.io.IOException - On I/O errors
  - createPathHandle
```
protected HdfsPathHandle createPathHandle(org.apache.hadoop.fs.FileStatus st,
                                          org.apache.hadoop.fs.Options.HandleOpt... opts)
```
    Create a handle to an HDFS file.
    
    Overrides:
    
    createPathHandle in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    st - HdfsFileStatus instance from NameNode
    
    opts - Standard handle arguments
    
    Returns:
    
    A handle to the file.
    
    Throws:
    
    java.lang.IllegalArgumentException - If the FileStatus instance refers to a directory, symlink, or another namesystem.
    
    java.lang.UnsupportedOperationException - If opts are not specified or both data and location are not allowed to change.
  - append
```
public org.apache.hadoop.fs.FSDataOutputStream append(org.apache.hadoop.fs.Path f,
                                                      int bufferSize,
                                                      org.apache.hadoop.util.Progressable progress)
                                               throws java.io.IOException
```
    Specified by:
    
    append in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - append
```
public org.apache.hadoop.fs.FSDataOutputStream append(org.apache.hadoop.fs.Path f,
                                                      int bufferSize,
                                                      org.apache.hadoop.util.Progressable progress,
                                                      boolean appendToNewBlock)
                                               throws java.io.IOException
```
    Overrides:
    
    append in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - append
```
public org.apache.hadoop.fs.FSDataOutputStream append(org.apache.hadoop.fs.Path f,
                                                      java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                                      int bufferSize,
                                                      org.apache.hadoop.util.Progressable progress)
                                               throws java.io.IOException
```
    Append to an existing file (optional operation).
    
    Parameters:
    
    f - the existing file to be appended.
    
    flag - Flags for the Append operation. CreateFlag.APPEND is mandatory to be present.
    
    bufferSize - the size of the buffer to be used.
    
    progress - for reporting progress if it is not null.
    
    Returns:
    
    Returns instance of FSDataOutputStream
    
    Throws:
    
    java.io.IOException
  - append
```
public org.apache.hadoop.fs.FSDataOutputStream append(org.apache.hadoop.fs.Path f,
                                                      java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                                      int bufferSize,
                                                      org.apache.hadoop.util.Progressable progress,
                                                      java.net.InetSocketAddress[] favoredNodes)
                                               throws java.io.IOException
```
    Append to an existing file (optional operation).
    
    Parameters:
    
    f - the existing file to be appended.
    
    flag - Flags for the Append operation. CreateFlag.APPEND is mandatory to be present.
    
    bufferSize - the size of the buffer to be used.
    
    progress - for reporting progress if it is not null.
    
    favoredNodes - Favored nodes for new blocks
    
    Returns:
    
    Returns instance of FSDataOutputStream
    
    Throws:
    
    java.io.IOException
  - create
```
public org.apache.hadoop.fs.FSDataOutputStream create(org.apache.hadoop.fs.Path f,
                                                      org.apache.hadoop.fs.permission.FsPermission permission,
                                                      boolean overwrite,
                                                      int bufferSize,
                                                      short replication,
                                                      long blockSize,
                                                      org.apache.hadoop.util.Progressable progress)
                                               throws java.io.IOException
```
    Specified by:
    
    create in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - create
```
public HdfsDataOutputStream create(org.apache.hadoop.fs.Path f,
                                   org.apache.hadoop.fs.permission.FsPermission permission,
                                   boolean overwrite,
                                   int bufferSize,
                                   short replication,
                                   long blockSize,
                                   org.apache.hadoop.util.Progressable progress,
                                   java.net.InetSocketAddress[] favoredNodes)
                            throws java.io.IOException
```
    Same as create(Path, FsPermission, boolean, int, short, long, Progressable) 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. And with favored nodes, blocks will be pinned on the datanodes to prevent balancing move the block. HDFS could move the blocks during 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 org.apache.hadoop.fs.FSDataOutputStream create(org.apache.hadoop.fs.Path f,
                                                      org.apache.hadoop.fs.permission.FsPermission permission,
                                                      java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> cflags,
                                                      int bufferSize,
                                                      short replication,
                                                      long blockSize,
                                                      org.apache.hadoop.util.Progressable progress,
                                                      org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)
                                               throws java.io.IOException
```
    Overrides:
    
    create in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - primitiveCreate
```
protected HdfsDataOutputStream primitiveCreate(org.apache.hadoop.fs.Path f,
                                               org.apache.hadoop.fs.permission.FsPermission absolutePermission,
                                               java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                               int bufferSize,
                                               short replication,
                                               long blockSize,
                                               org.apache.hadoop.util.Progressable progress,
                                               org.apache.hadoop.fs.Options.ChecksumOpt checksumOpt)
                                        throws java.io.IOException
```
    Overrides:
    
    primitiveCreate in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - createNonRecursive
```
public org.apache.hadoop.fs.FSDataOutputStream createNonRecursive(org.apache.hadoop.fs.Path f,
                                                                  org.apache.hadoop.fs.permission.FsPermission permission,
                                                                  java.util.EnumSet<org.apache.hadoop.fs.CreateFlag> flag,
                                                                  int bufferSize,
                                                                  short replication,
                                                                  long blockSize,
                                                                  org.apache.hadoop.util.Progressable progress)
                                                           throws java.io.IOException
```
    Same as create(), except fails if parent directory doesn't already exist.
    
    Overrides:
    
    createNonRecursive in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setReplication
```
public boolean setReplication(org.apache.hadoop.fs.Path src,
                              short replication)
                       throws java.io.IOException
```
    Overrides:
    
    setReplication in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setStoragePolicy
```
public void setStoragePolicy(org.apache.hadoop.fs.Path src,
                             java.lang.String policyName)
                      throws java.io.IOException
```
    Set the source path to the specified storage policy.
    
    Overrides:
    
    setStoragePolicy in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    src - The source path referring to either a directory or a file.
    
    policyName - The name of the storage policy.
    
    Throws:
    
    java.io.IOException
  - unsetStoragePolicy
```
public void unsetStoragePolicy(org.apache.hadoop.fs.Path src)
                        throws java.io.IOException
```
    Overrides:
    
    unsetStoragePolicy in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getStoragePolicy
```
public org.apache.hadoop.fs.BlockStoragePolicySpi getStoragePolicy(org.apache.hadoop.fs.Path path)
                                                            throws java.io.IOException
```
    Overrides:
    
    getStoragePolicy in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getAllStoragePolicies
```
public java.util.Collection<BlockStoragePolicy> getAllStoragePolicies()
                                                               throws java.io.IOException
```
    Overrides:
    
    getAllStoragePolicies in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getBytesWithFutureGenerationStamps
```
public long getBytesWithFutureGenerationStamps()
                                        throws java.io.IOException
```
    Returns number of bytes within blocks with future generation stamp. These are bytes that will be potentially deleted if we forceExit from safe mode.
    
    Returns:
    
    number of bytes.
    
    Throws:
    
    java.io.IOException
  - getStoragePolicies
```
@Deprecated
public BlockStoragePolicy[] getStoragePolicies()
                                        throws java.io.IOException
```
    Deprecated.
    
    Deprecated. Prefer FileSystem.getAllStoragePolicies()
    
    Throws:
    
    java.io.IOException
  - concat
```
public void concat(org.apache.hadoop.fs.Path trg,
                   org.apache.hadoop.fs.Path[] psrcs)
            throws java.io.IOException
```
    Move blocks from srcs to trg and delete srcs afterwards. The file block sizes must be the same.
    
    Overrides:
    
    concat in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    trg - existing file to append to
    
    psrcs - list of files (same block size, same replication)
    
    Throws:
    
    java.io.IOException
  - rename
```
public boolean rename(org.apache.hadoop.fs.Path src,
                      org.apache.hadoop.fs.Path dst)
               throws java.io.IOException
```
    Specified by:
    
    rename in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - rename
```
public void rename(org.apache.hadoop.fs.Path src,
                   org.apache.hadoop.fs.Path dst,
                   org.apache.hadoop.fs.Options.Rename... options)
            throws java.io.IOException
```
    This rename operation is guaranteed to be atomic.
    
    Overrides:
    
    rename in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - truncate
```
public boolean truncate(org.apache.hadoop.fs.Path f,
                        long newLength)
                 throws java.io.IOException
```
    Overrides:
    
    truncate in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - delete
```
public boolean delete(org.apache.hadoop.fs.Path f,
                      boolean recursive)
               throws java.io.IOException
```
    Specified by:
    
    delete in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getContentSummary
```
public org.apache.hadoop.fs.ContentSummary getContentSummary(org.apache.hadoop.fs.Path f)
                                                      throws java.io.IOException
```
    Overrides:
    
    getContentSummary in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getQuotaUsage
```
public org.apache.hadoop.fs.QuotaUsage getQuotaUsage(org.apache.hadoop.fs.Path f)
                                              throws java.io.IOException
```
    Overrides:
    
    getQuotaUsage in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setQuota
```
public void setQuota(org.apache.hadoop.fs.Path src,
                     long namespaceQuota,
                     long storagespaceQuota)
              throws java.io.IOException
```
    Set a directory's quotas
    
    Overrides:
    
    setQuota in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.setQuota(String, long, long, StorageType)
  - setQuotaByStorageType
```
public void setQuotaByStorageType(org.apache.hadoop.fs.Path src,
                                  org.apache.hadoop.fs.StorageType type,
                                  long quota)
                           throws java.io.IOException
```
    Set the per type storage quota of a directory.
    
    Overrides:
    
    setQuotaByStorageType in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    src - target directory whose quota is to be modified.
    
    type - storage type of the specific storage type quota to be modified.
    
    quota - value of the specific storage type quota to be modified. Maybe HdfsConstants.QUOTA_RESET to clear quota by storage type.
    
    Throws:
    
    java.io.IOException
  - listStatus
```
public org.apache.hadoop.fs.FileStatus[] listStatus(org.apache.hadoop.fs.Path p)
                                             throws java.io.IOException
```
    List all the entries of a directory Note that this operation is not atomic for a large directory. The entries of a directory may be fetched from NameNode multiple times. It only guarantees that each name occurs once if a directory undergoes changes between the calls. If any of the the immediate children of the given path f is a symlink, the returned FileStatus object of that children would be represented as a symlink. It will not be resolved to the target path and will not get the target path FileStatus object. The target path will be available via getSymlink on that children's FileStatus object. Since it represents as symlink, isDirectory on that children's FileStatus will return false. If you want to get the FileStatus of target path for that children, you may want to use GetFileStatus API with that children's symlink path. Please see getFileStatus(Path f)
    
    Specified by:
    
    listStatus in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - listLocatedStatus
```
protected org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.LocatedFileStatus> listLocatedStatus(org.apache.hadoop.fs.Path p,
                                                                                                        org.apache.hadoop.fs.PathFilter filter)
                                                                                                 throws java.io.IOException
```
    The BlockLocation of returned LocatedFileStatus will have different formats for replicated and erasure coded file. Please refer to FileSystem.getFileBlockLocations(FileStatus, long, long) for more details.
    
    Overrides:
    
    listLocatedStatus in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - listStatusIterator
```
public org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.FileStatus> listStatusIterator(org.apache.hadoop.fs.Path p)
                                                                                        throws java.io.IOException
```
    Returns a remote iterator so that followup calls are made on demand while consuming the entries. This reduces memory consumption during listing of a large directory.
    
    Overrides:
    
    listStatusIterator in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    p - target path
    
    Returns:
    
    remote iterator
    
    Throws:
    
    java.io.IOException
  - batchedListStatusIterator
```
public org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.PartialListing<org.apache.hadoop.fs.FileStatus>> batchedListStatusIterator(java.util.List<org.apache.hadoop.fs.Path> paths)
                                                                                                                                    throws java.io.IOException
```
    Specified by:
    
    batchedListStatusIterator in interface org.apache.hadoop.fs.BatchListingOperations
    
    Throws:
    
    java.io.IOException
  - batchedListLocatedStatusIterator
```
public org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.PartialListing<org.apache.hadoop.fs.LocatedFileStatus>> batchedListLocatedStatusIterator(java.util.List<org.apache.hadoop.fs.Path> paths)
                                                                                                                                                  throws java.io.IOException
```
    Specified by:
    
    batchedListLocatedStatusIterator in interface org.apache.hadoop.fs.BatchListingOperations
    
    Throws:
    
    java.io.IOException
  - mkdir
```
public boolean mkdir(org.apache.hadoop.fs.Path f,
                     org.apache.hadoop.fs.permission.FsPermission permission)
              throws java.io.IOException
```
    Create a directory, only when the parent directories exist. See FsPermission.applyUMask(FsPermission) for details of how the permission is applied.
    
    Parameters:
    
    f - The path to create
    
    permission - The permission. See FsPermission#applyUMask for details about how this is used to calculate the effective permission.
    
    Throws:
    
    java.io.IOException
  - mkdirs
```
public boolean mkdirs(org.apache.hadoop.fs.Path f,
                      org.apache.hadoop.fs.permission.FsPermission permission)
               throws java.io.IOException
```
    Create a directory and its parent directories. See FsPermission.applyUMask(FsPermission) for details of how the permission is applied.
    
    Specified by:
    
    mkdirs in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    f - The path to create
    
    permission - The permission. See FsPermission#applyUMask for details about how this is used to calculate the effective permission.
    
    Throws:
    
    java.io.IOException
  - primitiveMkdir
```
protected boolean primitiveMkdir(org.apache.hadoop.fs.Path f,
                                 org.apache.hadoop.fs.permission.FsPermission absolutePermission)
                          throws java.io.IOException
```
    Overrides:
    
    primitiveMkdir in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - close
```
public void close()
           throws java.io.IOException
```
    Specified by:
    
    close in interface java.lang.AutoCloseable
    
    Specified by:
    
    close in interface java.io.Closeable
    
    Overrides:
    
    close in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object
  - getClient
```
@Private
@VisibleForTesting
public DFSClient getClient()
```
  - getStatus
```
public org.apache.hadoop.fs.FsStatus getStatus(org.apache.hadoop.fs.Path p)
                                        throws java.io.IOException
```
    Overrides:
    
    getStatus in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - 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
  - getPendingDeletionBlocksCount
```
public long getPendingDeletionBlocksCount()
                                   throws java.io.IOException
```
    Returns count of blocks pending on deletion.
    
    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
  - 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
  - listCorruptFileBlocks
```
public org.apache.hadoop.fs.RemoteIterator<org.apache.hadoop.fs.Path> listCorruptFileBlocks(org.apache.hadoop.fs.Path path)
                                                                                     throws java.io.IOException
```
    Overrides:
    
    listCorruptFileBlocks in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getDataNodeStats
```
public DatanodeInfo[] getDataNodeStats()
                                throws java.io.IOException
```
    Returns:
    
    datanode statistics.
    
    Throws:
    
    java.io.IOException
  - getDataNodeStats
```
public DatanodeInfo[] getDataNodeStats(HdfsConstants.DatanodeReportType type)
                                throws java.io.IOException
```
    Returns:
    
    datanode statistics for the given type.
    
    Throws:
    
    java.io.IOException
  - setSafeMode
```
public boolean setSafeMode(org.apache.hadoop.fs.SafeModeAction action)
                    throws java.io.IOException
```
    Enter, leave or get safe mode.
    
    Specified by:
    
    setSafeMode in interface org.apache.hadoop.fs.SafeMode
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.setSafeMode( HdfsConstants.SafeModeAction,boolean)
  - setSafeMode
```
public boolean setSafeMode(org.apache.hadoop.fs.SafeModeAction action,
                           boolean isChecked)
                    throws java.io.IOException
```
    Enter, leave or get safe mode.
    
    Specified by:
    
    setSafeMode in interface org.apache.hadoop.fs.SafeMode
    
    Parameters:
    
    action - One of SafeModeAction.ENTER, SafeModeAction.LEAVE and SafeModeAction.GET.
    
    isChecked - If true check only for Active NNs status, else check first NN's status.
    
    Throws:
    
    java.io.IOException
  - setSafeMode
```
@Deprecated
public boolean setSafeMode(HdfsConstants.SafeModeAction action)
                    throws java.io.IOException
```
    Deprecated.
    please instead use setSafeMode(SafeModeAction).
    
    Enter, leave or get safe mode.
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.setSafeMode(HdfsConstants.SafeModeAction, boolean)
  - setSafeMode
```
@Deprecated
public boolean setSafeMode(HdfsConstants.SafeModeAction action,
                           boolean isChecked)
                    throws java.io.IOException
```
    Deprecated.
    please instead use setSafeMode(SafeModeAction, boolean).
    
    Enter, leave or get safe mode.
    
    Parameters:
    
    action - One of SafeModeAction.ENTER, SafeModeAction.LEAVE and SafeModeAction.GET.
    
    isChecked - If true check only for Active NNs status, else check first NN's status.
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.setSafeMode(HdfsConstants.SafeModeAction, boolean)
  - saveNamespace
```
public boolean saveNamespace(long timeWindow,
                             long txGap)
                      throws java.io.IOException
```
    Save namespace image.
    
    Parameters:
    
    timeWindow - NameNode can ignore this command if the latest checkpoint was done within the given time period (in seconds).
    
    Returns:
    
    true if a new checkpoint has been made
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.saveNamespace(long, long)
  - saveNamespace
```
public void saveNamespace()
                   throws java.io.IOException
```
    Save namespace image. NameNode always does the checkpoint.
    
    Throws:
    
    java.io.IOException
  - rollEdits
```
public long rollEdits()
               throws java.io.IOException
```
    Rolls the edit log on the active NameNode. Requires super-user privileges.
    
    Returns:
    
    the transaction ID of the newly created segment
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.rollEdits()
  - restoreFailedStorage
```
public boolean restoreFailedStorage(java.lang.String arg)
                             throws java.io.IOException
```
    enable/disable/check restoreFaileStorage.
    
    Throws:
    
    java.io.IOException
    
    See Also:
    
    ClientProtocol.restoreFailedStorage(String arg)
  - refreshNodes
```
public void refreshNodes()
                  throws java.io.IOException
```
    Refreshes the list of hosts and excluded hosts from the configured files.
    
    Throws:
    
    java.io.IOException
  - finalizeUpgrade
```
public void finalizeUpgrade()
                     throws java.io.IOException
```
    Finalize previously upgraded files system state.
    
    Throws:
    
    java.io.IOException
  - upgradeStatus
```
public boolean upgradeStatus()
                      throws java.io.IOException
```
    Get status of upgrade - finalized or not.
    
    Returns:
    
    true if upgrade is finalized or if no upgrade is in progress and false otherwise.
    
    Throws:
    
    java.io.IOException
  - rollingUpgrade
```
public RollingUpgradeInfo rollingUpgrade(HdfsConstants.RollingUpgradeAction action)
                                  throws java.io.IOException
```
    Rolling upgrade: prepare/finalize/query.
    
    Throws:
    
    java.io.IOException
  - metaSave
```
public void metaSave(java.lang.String pathname)
              throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - getServerDefaults
```
public org.apache.hadoop.fs.FsServerDefaults getServerDefaults()
                                                        throws java.io.IOException
```
    Overrides:
    
    getServerDefaults in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getFileStatus
```
public org.apache.hadoop.fs.FileStatus getFileStatus(org.apache.hadoop.fs.Path f)
                                              throws java.io.IOException
```
    Returns the stat information about the file. If the given path is a symlink, the path will be resolved to a target path and it will get the resolved path's FileStatus object. It will not be represented as a symlink and isDirectory API returns true if the resolved path is a directory, false otherwise.
    
    Specified by:
    
    getFileStatus in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.FileNotFoundException - if the file does not exist.
    
    java.io.IOException
  - msync
```
public void msync()
           throws java.io.IOException
```
    Synchronize client metadata state with Active NameNode.
    In HA the client synchronizes its state with the Active NameNode in order to guarantee subsequent read consistency from Observer Nodes.
    
    Overrides:
    
    msync in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - createSymlink
```
public void createSymlink(org.apache.hadoop.fs.Path target,
                          org.apache.hadoop.fs.Path link,
                          boolean createParent)
                   throws java.io.IOException
```
    Overrides:
    
    createSymlink in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - supportsSymlinks
```
public boolean supportsSymlinks()
```
    Overrides:
    
    supportsSymlinks in class org.apache.hadoop.fs.FileSystem
  - getFileLinkStatus
```
public org.apache.hadoop.fs.FileStatus getFileLinkStatus(org.apache.hadoop.fs.Path f)
                                                  throws java.io.IOException
```
    Overrides:
    
    getFileLinkStatus in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getLinkTarget
```
public org.apache.hadoop.fs.Path getLinkTarget(org.apache.hadoop.fs.Path f)
                                        throws java.io.IOException
```
    Overrides:
    
    getLinkTarget in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - resolveLink
```
protected org.apache.hadoop.fs.Path resolveLink(org.apache.hadoop.fs.Path f)
                                         throws java.io.IOException
```
    Overrides:
    
    resolveLink in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getFileChecksum
```
public org.apache.hadoop.fs.FileChecksum getFileChecksum(org.apache.hadoop.fs.Path f)
                                                  throws java.io.IOException
```
    Overrides:
    
    getFileChecksum in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getFileChecksum
```
public org.apache.hadoop.fs.FileChecksum getFileChecksum(org.apache.hadoop.fs.Path f,
                                                         long length)
                                                  throws java.io.IOException
```
    Overrides:
    
    getFileChecksum in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setPermission
```
public void setPermission(org.apache.hadoop.fs.Path p,
                          org.apache.hadoop.fs.permission.FsPermission permission)
                   throws java.io.IOException
```
    Overrides:
    
    setPermission in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setOwner
```
public void setOwner(org.apache.hadoop.fs.Path p,
                     java.lang.String username,
                     java.lang.String groupname)
              throws java.io.IOException
```
    Overrides:
    
    setOwner in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setTimes
```
public void setTimes(org.apache.hadoop.fs.Path p,
                     long mtime,
                     long atime)
              throws java.io.IOException
```
    Overrides:
    
    setTimes in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getDefaultPort
```
protected int getDefaultPort()
```
    Overrides:
    
    getDefaultPort in class org.apache.hadoop.fs.FileSystem
  - getDelegationToken
```
public org.apache.hadoop.security.token.Token<DelegationTokenIdentifier> getDelegationToken(java.lang.String renewer)
                                                                                     throws java.io.IOException
```
    Specified by:
    
    getDelegationToken in interface org.apache.hadoop.security.token.DelegationTokenIssuer
    
    Overrides:
    
    getDelegationToken in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - 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. The bandwidth parameter is the max number of bytes per second of network bandwidth to be used by a datanode during balancing.
    
    Parameters:
    
    bandwidth - Balancer bandwidth in bytes per second for all datanodes.
    
    Throws:
    
    java.io.IOException
  - getCanonicalServiceName
```
public java.lang.String getCanonicalServiceName()
```
    Get a canonical service name for this file system. If the URI is logical, the hostname part of the URI will be returned.
    
    Specified by:
    
    getCanonicalServiceName in interface org.apache.hadoop.security.token.DelegationTokenIssuer
    
    Overrides:
    
    getCanonicalServiceName in class org.apache.hadoop.fs.FileSystem
    
    Returns:
    
    a service string that uniquely identifies this file system.
  - canonicalizeUri
```
protected java.net.URI canonicalizeUri(java.net.URI uri)
```
    Overrides:
    
    canonicalizeUri in class org.apache.hadoop.fs.FileSystem
  - isInSafeMode
```
public boolean isInSafeMode()
                     throws java.io.IOException
```
    Utility function that returns if the NameNode is in safemode or not. In HA mode, this API will return only ActiveNN's safemode status.
    
    Returns:
    
    true if NameNode is in safemode, false otherwise.
    
    Throws:
    
    java.io.IOException - when there is an issue communicating with the NameNode
  - isSnapshotTrashRootEnabled
```
public boolean isSnapshotTrashRootEnabled()
                                   throws java.io.IOException
```
    HDFS only. Returns if the NameNode enabled the snapshot trash root configuration dfs.namenode.snapshot.trashroot.enabled
    
    Returns:
    
    true if NameNode enabled snapshot trash root
    
    Throws:
    
    java.io.IOException - when there is an issue communicating with the NameNode
  - allowSnapshot
```
public void allowSnapshot(org.apache.hadoop.fs.Path path)
                   throws java.io.IOException
```
    Throws:
    
    java.io.IOException
    
    See Also:
    
    HdfsAdmin.allowSnapshot(Path)
  - disallowSnapshot
```
public void disallowSnapshot(org.apache.hadoop.fs.Path path)
                      throws java.io.IOException
```
    Throws:
    
    java.io.IOException
    
    See Also:
    
    HdfsAdmin.disallowSnapshot(Path)
  - createSnapshot
```
public org.apache.hadoop.fs.Path createSnapshot(org.apache.hadoop.fs.Path path,
                                                java.lang.String snapshotName)
                                         throws java.io.IOException
```
    Overrides:
    
    createSnapshot in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - renameSnapshot
```
public void renameSnapshot(org.apache.hadoop.fs.Path path,
                           java.lang.String snapshotOldName,
                           java.lang.String snapshotNewName)
                    throws java.io.IOException
```
    Overrides:
    
    renameSnapshot in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getSnapshottableDirListing
```
public SnapshottableDirectoryStatus[] getSnapshottableDirListing()
                                                          throws java.io.IOException
```
    Get the list of snapshottable directories that are owned by the current user. Return all the snapshottable directories if the current user is a super user.
    
    Returns:
    
    The list of all the current snapshottable directories.
    
    Throws:
    
    java.io.IOException - If an I/O error occurred.
  - getSnapshotListing
```
public SnapshotStatus[] getSnapshotListing(org.apache.hadoop.fs.Path snapshotRoot)
                                    throws java.io.IOException
```
    Returns:
    
    all the snapshots for a snapshottable directory
    
    Throws:
    
    java.io.IOException
  - deleteSnapshot
```
public void deleteSnapshot(org.apache.hadoop.fs.Path snapshotDir,
                           java.lang.String snapshotName)
                    throws java.io.IOException
```
    Overrides:
    
    deleteSnapshot in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - snapshotDiffReportListingRemoteIterator
```
public org.apache.hadoop.fs.RemoteIterator<SnapshotDiffReportListing> snapshotDiffReportListingRemoteIterator(org.apache.hadoop.fs.Path snapshotDir,
                                                                                                              java.lang.String fromSnapshot,
                                                                                                              java.lang.String toSnapshot)
                                                                                                       throws java.io.IOException
```
    Returns a remote iterator so that followup calls are made on demand while consuming the SnapshotDiffReportListing entries. This reduces memory consumption overhead in case the snapshotDiffReport is huge.
    
    Parameters:
    
    snapshotDir - full path of the directory where snapshots are taken
    
    fromSnapshot - snapshot name of the from point. Null indicates the current tree
    
    toSnapshot - snapshot name of the to point. Null indicates the current tree.
    
    Returns:
    
    Remote iterator
    
    Throws:
    
    java.io.IOException
  - getSnapshotDiffReport
```
public SnapshotDiffReport getSnapshotDiffReport(org.apache.hadoop.fs.Path 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:
    
    DFSClient.getSnapshotDiffReportListing(java.lang.String, java.lang.String, java.lang.String, byte[], int)
  - getSnapshotDiffReportListing
```
public SnapshotDiffReportListing getSnapshotDiffReportListing(org.apache.hadoop.fs.Path snapshotDir,
                                                              java.lang.String fromSnapshotName,
                                                              java.lang.String toSnapshotName,
                                                              java.lang.String snapshotDiffStartPath,
                                                              int snapshotDiffIndex)
                                                       throws java.io.IOException
```
    Get the difference between two snapshots of a directory iteratively.
    
    Parameters:
    
    snapshotDir - full path of the directory where snapshots are taken.
    
    fromSnapshotName - snapshot name of the from point. Null indicates the current tree.
    
    toSnapshotName - snapshot name of the to point. Null indicates the current tree.
    
    snapshotDiffStartPath - path relative to the snapshottable root directory from where the snapshotdiff computation needs to start.
    
    snapshotDiffIndex - index in the created or deleted list of the directory at which the snapshotdiff computation stopped during the last rpc call. -1 indicates the diff computation needs to start right from the start path.
    
    Returns:
    
    the difference report represented as a SnapshotDiffReportListing.
    
    Throws:
    
    java.io.IOException - if an I/O error occurred.
  - isFileClosed
```
public boolean isFileClosed(org.apache.hadoop.fs.Path src)
                     throws java.io.IOException
```
    Get the close status of a file
    
    Specified by:
    
    isFileClosed in interface org.apache.hadoop.fs.LeaseRecoverable
    
    Parameters:
    
    src - The path to the file
    
    Returns:
    
    return true if file is closed
    
    Throws:
    
    java.io.FileNotFoundException - if the file does not exist.
    
    java.io.IOException - If an I/O error occurred
  - addCacheDirective
```
public long addCacheDirective(CacheDirectiveInfo info)
                       throws java.io.IOException
```
    Throws:
    
    java.io.IOException
    
    See Also:
    
    addCacheDirective(CacheDirectiveInfo, EnumSet)
  - addCacheDirective
```
public long addCacheDirective(CacheDirectiveInfo info,
                              java.util.EnumSet<CacheFlag> flags)
                       throws java.io.IOException
```
    Add a new CacheDirective.
    
    Parameters:
    
    info - Information about a directive to add.
    
    flags - CacheFlags to use for this operation.
    
    Returns:
    
    the ID of the directive that was created.
    
    Throws:
    
    java.io.IOException - if the directive could not be added
  - modifyCacheDirective
```
public void modifyCacheDirective(CacheDirectiveInfo info)
                          throws java.io.IOException
```
    Throws:
    
    java.io.IOException
    
    See Also:
    
    modifyCacheDirective(CacheDirectiveInfo, EnumSet)
  - modifyCacheDirective
```
public void modifyCacheDirective(CacheDirectiveInfo info,
                                 java.util.EnumSet<CacheFlag> flags)
                          throws java.io.IOException
```
    Modify a CacheDirective.
    
    Parameters:
    
    info - Information about the directive to modify. You must set the ID to indicate which CacheDirective you want to modify.
    
    flags - CacheFlags to use for this operation.
    
    Throws:
    
    java.io.IOException - if the directive could not be modified
  - removeCacheDirective
```
public void removeCacheDirective(long id)
                          throws java.io.IOException
```
    Remove a CacheDirectiveInfo.
    
    Parameters:
    
    id - identifier of the CacheDirectiveInfo to remove
    
    Throws:
    
    java.io.IOException - if the directive could not be removed
  - listCacheDirectives
```
public org.apache.hadoop.fs.RemoteIterator<CacheDirectiveEntry> listCacheDirectives(CacheDirectiveInfo filter)
                                                                             throws java.io.IOException
```
    List cache directives. Incrementally fetches results from the server.
    
    Parameters:
    
    filter - Filter parameters to use when listing the directives, null to list all directives visible to us.
    
    Returns:
    
    A RemoteIterator which returns CacheDirectiveInfo objects.
    
    Throws:
    
    java.io.IOException
  - addCachePool
```
public void addCachePool(CachePoolInfo info)
                  throws java.io.IOException
```
    Add a cache pool.
    
    Parameters:
    
    info - The request to add a cache pool.
    
    Throws:
    
    java.io.IOException - If the request could not be completed.
  - modifyCachePool
```
public void modifyCachePool(CachePoolInfo info)
                     throws java.io.IOException
```
    Modify an existing cache pool.
    
    Parameters:
    
    info - The request to modify a cache pool.
    
    Throws:
    
    java.io.IOException - If the request could not be completed.
  - removeCachePool
```
public void removeCachePool(java.lang.String poolName)
                     throws java.io.IOException
```
    Remove a cache pool.
    
    Parameters:
    
    poolName - Name of the cache pool to remove.
    
    Throws:
    
    java.io.IOException - if the cache pool did not exist, or could not be removed.
  - listCachePools
```
public org.apache.hadoop.fs.RemoteIterator<CachePoolEntry> listCachePools()
                                                                   throws java.io.IOException
```
    List all cache pools.
    
    Returns:
    
    A remote iterator from which you can get CachePoolEntry objects. Requests will be made as needed.
    
    Throws:
    
    java.io.IOException - If there was an error listing cache pools.
  - modifyAclEntries
```
public void modifyAclEntries(org.apache.hadoop.fs.Path path,
                             java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)
                      throws java.io.IOException
```
    Overrides:
    
    modifyAclEntries in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - removeAclEntries
```
public void removeAclEntries(org.apache.hadoop.fs.Path path,
                             java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)
                      throws java.io.IOException
```
    Overrides:
    
    removeAclEntries in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - removeDefaultAcl
```
public void removeDefaultAcl(org.apache.hadoop.fs.Path path)
                      throws java.io.IOException
```
    Overrides:
    
    removeDefaultAcl in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - removeAcl
```
public void removeAcl(org.apache.hadoop.fs.Path path)
               throws java.io.IOException
```
    Overrides:
    
    removeAcl in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - setAcl
```
public void setAcl(org.apache.hadoop.fs.Path path,
                   java.util.List<org.apache.hadoop.fs.permission.AclEntry> aclSpec)
            throws java.io.IOException
```
    Overrides:
    
    setAcl in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getAclStatus
```
public org.apache.hadoop.fs.permission.AclStatus getAclStatus(org.apache.hadoop.fs.Path path)
                                                       throws java.io.IOException
```
    Overrides:
    
    getAclStatus in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - createEncryptionZone
```
public void createEncryptionZone(org.apache.hadoop.fs.Path path,
                                 java.lang.String keyName)
                          throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - getEZForPath
```
public EncryptionZone getEZForPath(org.apache.hadoop.fs.Path path)
                            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(org.apache.hadoop.fs.Path 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
  - getFileEncryptionInfo
```
public org.apache.hadoop.fs.FileEncryptionInfo getFileEncryptionInfo(org.apache.hadoop.fs.Path path)
                                                              throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - provisionEZTrash
```
public void provisionEZTrash(org.apache.hadoop.fs.Path path,
                             org.apache.hadoop.fs.permission.FsPermission trashPermission)
                      throws java.io.IOException
```
    Throws:
    
    java.io.IOException
  - provisionSnapshotTrash
```
public org.apache.hadoop.fs.Path provisionSnapshotTrash(org.apache.hadoop.fs.Path path,
                                                        org.apache.hadoop.fs.permission.FsPermission trashPermission)
                                                 throws java.io.IOException
```
    HDFS only. Provision snapshottable directory trash.
    
    Parameters:
    
    path - Path to a snapshottable directory.
    
    trashPermission - Expected FsPermission of the trash root.
    
    Returns:
    
    Path of the provisioned trash root
    
    Throws:
    
    java.io.IOException
  - setXAttr
```
public void setXAttr(org.apache.hadoop.fs.Path path,
                     java.lang.String name,
                     byte[] value,
                     java.util.EnumSet<org.apache.hadoop.fs.XAttrSetFlag> flag)
              throws java.io.IOException
```
    Overrides:
    
    setXAttr in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getXAttr
```
public byte[] getXAttr(org.apache.hadoop.fs.Path path,
                       java.lang.String name)
                throws java.io.IOException
```
    Overrides:
    
    getXAttr in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getXAttrs
```
public java.util.Map<java.lang.String,byte[]> getXAttrs(org.apache.hadoop.fs.Path path)
                                                       throws java.io.IOException
```
    Overrides:
    
    getXAttrs in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getXAttrs
```
public java.util.Map<java.lang.String,byte[]> getXAttrs(org.apache.hadoop.fs.Path path,
                                                              java.util.List<java.lang.String> names)
                                                       throws java.io.IOException
```
    Overrides:
    
    getXAttrs in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - listXAttrs
```
public java.util.List<java.lang.String> listXAttrs(org.apache.hadoop.fs.Path path)
                                            throws java.io.IOException
```
    Overrides:
    
    listXAttrs in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - removeXAttr
```
public void removeXAttr(org.apache.hadoop.fs.Path path,
                        java.lang.String name)
                 throws java.io.IOException
```
    Overrides:
    
    removeXAttr in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - access
```
public void access(org.apache.hadoop.fs.Path path,
                   org.apache.hadoop.fs.permission.FsAction mode)
            throws java.io.IOException
```
    Overrides:
    
    access in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - 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
  - getAdditionalTokenIssuers
```
public org.apache.hadoop.security.token.DelegationTokenIssuer[] getAdditionalTokenIssuers()
                                                                                   throws java.io.IOException
```
    Specified by:
    
    getAdditionalTokenIssuers in interface org.apache.hadoop.security.token.DelegationTokenIssuer
    
    Overrides:
    
    getAdditionalTokenIssuers in class org.apache.hadoop.fs.FileSystem
    
    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
  - setErasureCodingPolicy
```
public void setErasureCodingPolicy(org.apache.hadoop.fs.Path path,
                                   java.lang.String ecPolicyName)
                            throws java.io.IOException
```
    Set the source path to the specified erasure coding policy.
    
    Parameters:
    
    path - The directory to set the policy
    
    ecPolicyName - The erasure coding policy name.
    
    Throws:
    
    java.io.IOException
  - satisfyStoragePolicy
```
public void satisfyStoragePolicy(org.apache.hadoop.fs.Path path)
                          throws java.io.IOException
```
    Set the source path to satisfy storage policy.
    
    Overrides:
    
    satisfyStoragePolicy in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    path - The source path referring to either a directory or a file.
    
    Throws:
    
    java.io.IOException
  - getErasureCodingPolicy
```
public ErasureCodingPolicy getErasureCodingPolicy(org.apache.hadoop.fs.Path path)
                                           throws java.io.IOException
```
    Get erasure coding policy information for the specified path.
    
    Parameters:
    
    path - The path of the file or directory
    
    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
  - getAllErasureCodingPolicies
```
public java.util.Collection<ErasureCodingPolicyInfo> getAllErasureCodingPolicies()
                                                                          throws java.io.IOException
```
    Retrieve all the erasure coding policies supported by this file system, including enabled, disabled and removed policies, but excluding REPLICATION policy.
    
    Returns:
    
    all erasure coding policies supported by this file system.
    
    Throws:
    
    java.io.IOException
  - getAllErasureCodingCodecs
```
public java.util.Map<java.lang.String,java.lang.String> getAllErasureCodingCodecs()
                                                                                 throws java.io.IOException
```
    Retrieve all the erasure coding codecs and coders supported by this file system.
    
    Returns:
    
    all erasure coding codecs and coders supported by this file system.
    
    Throws:
    
    java.io.IOException
  - addErasureCodingPolicies
```
public AddErasureCodingPolicyResponse[] addErasureCodingPolicies(ErasureCodingPolicy[] policies)
                                                          throws java.io.IOException
```
    Add Erasure coding policies to HDFS. For each policy input, schema and cellSize are musts, name and id are ignored. They will be automatically created and assigned by Namenode once the policy is successfully added, and will be returned in the response; policy states will be set to DISABLED automatically.
    
    Parameters:
    
    policies - The user defined ec policy list to add.
    
    Returns:
    
    Return the response list of adding operations.
    
    Throws:
    
    java.io.IOException
  - removeErasureCodingPolicy
```
public void removeErasureCodingPolicy(java.lang.String ecPolicyName)
                               throws java.io.IOException
```
    Remove erasure coding policy.
    
    Parameters:
    
    ecPolicyName - The name of the policy to be removed.
    
    Throws:
    
    java.io.IOException
  - enableErasureCodingPolicy
```
public void enableErasureCodingPolicy(java.lang.String ecPolicyName)
                               throws java.io.IOException
```
    Enable erasure coding policy.
    
    Parameters:
    
    ecPolicyName - The name of the policy to be enabled.
    
    Throws:
    
    java.io.IOException
  - disableErasureCodingPolicy
```
public void disableErasureCodingPolicy(java.lang.String ecPolicyName)
                                throws java.io.IOException
```
    Disable erasure coding policy.
    
    Parameters:
    
    ecPolicyName - The name of the policy to be disabled.
    
    Throws:
    
    java.io.IOException
  - unsetErasureCodingPolicy
```
public void unsetErasureCodingPolicy(org.apache.hadoop.fs.Path path)
                              throws java.io.IOException
```
    Unset the erasure coding policy from the source path.
    
    Parameters:
    
    path - The directory to unset the policy
    
    Throws:
    
    java.io.IOException
  - getECTopologyResultForPolicies
```
public ECTopologyVerifierResult getECTopologyResultForPolicies(java.lang.String... policyNames)
                                                        throws java.io.IOException
```
    Verifies if the given policies are supported in the given cluster setup. If not policy is specified checks for all enabled policies.
    
    Parameters:
    
    policyNames - name of policies.
    
    Returns:
    
    the result if the given policies are supported in the cluster setup
    
    Throws:
    
    java.io.IOException
  - getTrashRoot
```
public org.apache.hadoop.fs.Path getTrashRoot(org.apache.hadoop.fs.Path path)
```
    Get the root directory of Trash for a path in HDFS. 1. File in encryption zone returns /ez1/.Trash/username 2. File in snapshottable directory returns /snapdir1/.Trash/username if dfs.namenode.snapshot.trashroot.enabled is set to true. 3. In other cases, or encountered exception when checking the encryption zone or when checking snapshot root of the path, returns /users/username/.Trash Caller appends either Current or checkpoint timestamp for trash destination
    
    Overrides:
    
    getTrashRoot in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    path - the trash root of the path to be determined.
    
    Returns:
    
    trash root
  - getTrashRoots
```
public java.util.Collection<org.apache.hadoop.fs.FileStatus> getTrashRoots(boolean allUsers)
```
    Get all the trash roots of HDFS for current user or for all the users. 1. File deleted from encryption zones e.g., ez1 rooted at /ez1 has its trash root at /ez1/.Trash/$USER 2. File deleted from snapshottable directories if dfs.namenode.snapshot.trashroot.enabled is set to true. e.g., snapshottable directory /snapdir1 has its trash root at /snapdir1/.Trash/$USER 3. File deleted from other directories /user/username/.Trash
    
    Overrides:
    
    getTrashRoots in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    allUsers - return trashRoots of all users if true, used by emptier
    
    Returns:
    
    trash roots of HDFS
  - fixRelativePart
```
protected org.apache.hadoop.fs.Path fixRelativePart(org.apache.hadoop.fs.Path p)
```
    Overrides:
    
    fixRelativePart in class org.apache.hadoop.fs.FileSystem
  - createFile
```
public DistributedFileSystem.HdfsDataOutputStreamBuilder createFile(org.apache.hadoop.fs.Path path)
```
    Create a HdfsDataOutputStreamBuilder to create a file on DFS. Similar to FileSystem.create(Path), file is overwritten by default.
    
    Overrides:
    
    createFile in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    path - the path of the file to create.
    
    Returns:
    
    A HdfsDataOutputStreamBuilder for creating a file.
  - listOpenFiles
```
@Deprecated
public org.apache.hadoop.fs.RemoteIterator<OpenFileEntry> listOpenFiles()
                                                                 throws java.io.IOException
```
    Deprecated.
    
    Returns a RemoteIterator which can be used to list all open files currently managed by the NameNode. For large numbers of open files, iterator will fetch the list in batches of configured size.
    Since the list is fetched in batches, it does not represent a consistent snapshot of the all open files.
    This method can only be called by HDFS superusers.
    
    Throws:
    
    java.io.IOException
  - listOpenFiles
```
@Deprecated
public org.apache.hadoop.fs.RemoteIterator<OpenFileEntry> listOpenFiles(java.util.EnumSet<OpenFilesIterator.OpenFilesType> openFilesTypes)
                                                                 throws java.io.IOException
```
    Deprecated.
    
    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
```
    Throws:
    
    java.io.IOException
  - appendFile
```
public DistributedFileSystem.HdfsDataOutputStreamBuilder appendFile(org.apache.hadoop.fs.Path path)
```
    Create a DistributedFileSystem.HdfsDataOutputStreamBuilder to append a file on DFS.
    
    Overrides:
    
    appendFile in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    path - file path.
    
    Returns:
    
    A DistributedFileSystem.HdfsDataOutputStreamBuilder for appending a file.
  - hasPathCapability
```
public boolean hasPathCapability(org.apache.hadoop.fs.Path path,
                                 java.lang.String capability)
                          throws java.io.IOException
```
    HDFS client capabilities. Uses DfsPathCapabilities to keep WebHdfsFileSystem in sync.
    
    Specified by:
    
    hasPathCapability in interface org.apache.hadoop.fs.PathCapabilities
    
    Overrides:
    
    hasPathCapability in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - createMultipartUploader
```
public org.apache.hadoop.fs.MultipartUploaderBuilder createMultipartUploader(org.apache.hadoop.fs.Path basePath)
                                                                      throws java.io.IOException
```
    Overrides:
    
    createMultipartUploader in class org.apache.hadoop.fs.FileSystem
    
    Throws:
    
    java.io.IOException
  - getSlowDatanodeStats
```
public DatanodeInfo[] getSlowDatanodeStats()
                                    throws java.io.IOException
```
    Retrieve stats for slow running datanodes.
    
    Returns:
    
    An array of slow datanode info.
    
    Throws:
    
    java.io.IOException - If an I/O error occurs.
  - getLocatedBlocks
```
public LocatedBlocks getLocatedBlocks(org.apache.hadoop.fs.Path p,
                                      long start,
                                      long len)
                               throws java.io.IOException
```
    Returns LocatedBlocks of the corresponding HDFS file p from offset start for length len. This is similar to getFileBlockLocations(Path, long, long) except that it returns LocatedBlocks rather than BlockLocation array.
    
    Parameters:
    
    p - path representing the file of interest.
    
    start - offset
    
    len - length
    
    Returns:
    
    a LocatedBlocks object
    
    Throws:
    
    java.io.IOException
  - getEnclosingRoot
```
public org.apache.hadoop.fs.Path getEnclosingRoot(org.apache.hadoop.fs.Path path)
                                           throws java.io.IOException
```
    Return path of the enclosing root for a given path The enclosing root path is a common ancestor that should be used for temp and staging dirs as well as within encryption zones and other restricted directories.
    
    Overrides:
    
    getEnclosingRoot in class org.apache.hadoop.fs.FileSystem
    
    Parameters:
    
    path - file path to find the enclosing root path for
    
    Returns:
    
    a path to the enclosing root
    
    Throws:
    
    java.io.IOException - early checks like failure to resolve path cause IO failures

Class DistributedFileSystem

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.fs.FileSystem

Field Summary

Fields inherited from class org.apache.hadoop.fs.FileSystem

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

Constructor Summary

Method Summary

Methods inherited from class org.apache.hadoop.fs.FileSystem

Methods inherited from class org.apache.hadoop.conf.Configured

Methods inherited from class java.lang.Object

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

Constructor Detail

DistributedFileSystem

Method Detail

getScheme

getUri

initialize

getWorkingDirectory

getDefaultBlockSize

getDefaultReplication

setWorkingDirectory

getHomeDirectory

getHedgedReadMetrics

getFileBlockLocations

getFileBlockLocations

setVerifyChecksum

recoverLease

open

open

createPathHandle

append

append

append

append

create

create

create

primitiveCreate

createNonRecursive

setReplication

setStoragePolicy

unsetStoragePolicy

getStoragePolicy

getAllStoragePolicies

getBytesWithFutureGenerationStamps

getStoragePolicies

concat

rename

rename

truncate

delete

getContentSummary

getQuotaUsage

setQuota

setQuotaByStorageType

listStatus

listLocatedStatus

listStatusIterator

batchedListStatusIterator

batchedListLocatedStatusIterator

mkdir

mkdirs

primitiveMkdir

close

toString

getClient

getStatus

getMissingBlocksCount

getPendingDeletionBlocksCount

getMissingReplOneBlocksCount

getLowRedundancyBlocksCount

getCorruptBlocksCount

listCorruptFileBlocks

getDataNodeStats

getDataNodeStats

setSafeMode

setSafeMode

setSafeMode

setSafeMode