FileSystem (Apache Hadoop Common 2.0.6-alpha API)

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

All Implemented Interfaces:

Closeable, AutoCloseable, Configurable

Direct Known Subclasses:

FilterFileSystem, FTPFileSystem, KosmosFileSystem, NativeS3FileSystem, RawLocalFileSystem, S3FileSystem, ViewFileSystem
```
@InterfaceAudience.Public
@InterfaceStability.Stable
public abstract class FileSystem
extends Configured
implements Closeable
```
An abstract base class for a fairly generic filesystem. It may be implemented as a distributed filesystem, or as a "local" one that reflects the locally-connected disk. The local version exists for small Hadoop instances and for testing.
All user code that may potentially use the Hadoop Distributed File System should be written to use a FileSystem object. The Hadoop DFS is a multi-machine system that appears as a single disk. It's useful because of its fault tolerance and potentially very large capacity.
The local implementation is LocalFileSystem and distributed implementation is DistributedFileSystem.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class FileSystem.Statistics

Nested Classes
Modifier and Type	Class and Description
`static class`	`FileSystem.Statistics`

Field Summary

Fields
Modifier and Type	Field and Description
`static String`	`DEFAULT_FS`
`static String`	`FS_DEFAULT_NAME_KEY`
`static org.apache.commons.logging.Log`	`LOG`
`static int`	`SHUTDOWN_HOOK_PRIORITY` Priority of the FileSystem shutdown hook.
`protected FileSystem.Statistics`	`statistics` The statistics for this file system.

Constructor Summary

Constructors
Modifier Constructor and Description

protected FileSystem()

Constructors
Modifier	Constructor and Description
`protected`	`FileSystem()`

Method Summary

Methods
Modifier and Type	Method and Description
`FSDataOutputStream`	`append(Path f)` Append to an existing file (optional operation).
`FSDataOutputStream`	`append(Path f, int bufferSize)` Append to an existing file (optional operation).
`abstract FSDataOutputStream`	`append(Path f, int bufferSize, Progressable progress)` Append to an existing file (optional operation).
`boolean`	`cancelDeleteOnExit(Path f)` Cancel the deletion of the path when the FileSystem is closed
`protected void`	`checkPath(Path path)` Check that a Path belongs to this FileSystem.
`static void`	`clearStatistics()` Reset all statistics for all file systems
`void`	`close()` No more filesystem operations are needed.
`static void`	`closeAll()` Close all cached filesystems.
`static void`	`closeAllForUGI(org.apache.hadoop.security.UserGroupInformation ugi)` Close all cached filesystems for a given UGI.
`void`	`completeLocalOutput(Path fsOutputFile, Path tmpLocalFile)` Called when we're all done writing to the target.
`void`	`concat(Path trg, Path[] psrcs)` Concat existing files together.
`void`	`copyFromLocalFile(boolean delSrc, boolean overwrite, Path[] srcs, Path dst)` The src files are on the local disk.
`void`	`copyFromLocalFile(boolean delSrc, boolean overwrite, Path src, Path dst)` The src file is on the local disk.
`void`	`copyFromLocalFile(boolean delSrc, Path src, Path dst)` The src file is on the local disk.
`void`	`copyFromLocalFile(Path src, Path dst)` The src file is on the local disk.
`void`	`copyToLocalFile(boolean delSrc, Path src, Path dst)` The src file is under FS, and the dst is on the local disk.
`void`	`copyToLocalFile(boolean delSrc, Path src, Path dst, boolean useRawLocalFileSystem)` The src file is under FS, and the dst is on the local disk.
`void`	`copyToLocalFile(Path src, Path dst)` The src file is under FS, and the dst is on the local disk.
`static FSDataOutputStream`	`create(FileSystem fs, Path file, FsPermission permission)` create a file with the provided permission The permission of the file is set to be the provided permission as in setPermission, not permission&~umask It is implemented using two RPCs.
`FSDataOutputStream`	`create(Path f)` Create an FSDataOutputStream at the indicated Path.
`FSDataOutputStream`	`create(Path f, boolean overwrite)` Create an FSDataOutputStream at the indicated Path.
`FSDataOutputStream`	`create(Path f, boolean overwrite, int bufferSize)` Create an FSDataOutputStream at the indicated Path.
`FSDataOutputStream`	`create(Path f, boolean overwrite, int bufferSize, Progressable progress)` Create an FSDataOutputStream at the indicated Path with write-progress reporting.
`FSDataOutputStream`	`create(Path f, boolean overwrite, int bufferSize, short replication, long blockSize)` Create an FSDataOutputStream at the indicated Path.
`FSDataOutputStream`	`create(Path f, boolean overwrite, int bufferSize, short replication, long blockSize, Progressable progress)` Create an FSDataOutputStream at the indicated Path with write-progress reporting.
`abstract FSDataOutputStream`	`create(Path f, FsPermission permission, boolean overwrite, int bufferSize, short replication, long blockSize, Progressable progress)` Create an FSDataOutputStream at the indicated Path with write-progress reporting.
`FSDataOutputStream`	`create(Path f, FsPermission permission, EnumSet<CreateFlag> flags, int bufferSize, short replication, long blockSize, Progressable progress)` Create an FSDataOutputStream at the indicated Path with write-progress reporting.
`FSDataOutputStream`	`create(Path f, FsPermission permission, EnumSet<CreateFlag> flags, int bufferSize, short replication, long blockSize, Progressable progress, Options.ChecksumOpt checksumOpt)` Create an FSDataOutputStream at the indicated Path with a custom checksum option
`FSDataOutputStream`	`create(Path f, Progressable progress)` Create an FSDataOutputStream at the indicated Path with write-progress reporting.
`FSDataOutputStream`	`create(Path f, short replication)` Create an FSDataOutputStream at the indicated Path.
`FSDataOutputStream`	`create(Path f, short replication, Progressable progress)` Create an FSDataOutputStream at the indicated Path with write-progress reporting.
`boolean`	`createNewFile(Path f)` Creates the given Path as a brand-new zero-length file.
`FSDataOutputStream`	`createNonRecursive(Path f, boolean overwrite, int bufferSize, short replication, long blockSize, Progressable progress)` Deprecated. API only for 0.20-append
`FSDataOutputStream`	`createNonRecursive(Path f, FsPermission permission, boolean overwrite, int bufferSize, short replication, long blockSize, Progressable progress)` Deprecated. API only for 0.20-append
`FSDataOutputStream`	`createNonRecursive(Path f, FsPermission permission, EnumSet<CreateFlag> flags, int bufferSize, short replication, long blockSize, Progressable progress)` Deprecated. API only for 0.20-append
`boolean`	`delete(Path f)` Deprecated. Use `delete(Path, boolean)` instead.
`abstract boolean`	`delete(Path f, boolean recursive)` Delete a file.
`boolean`	`deleteOnExit(Path f)` Mark a path to be deleted when FileSystem is closed.
`boolean`	`exists(Path f)` Check if exists.
`static FileSystem`	`get(Configuration conf)` Returns the configured filesystem implementation.
`static FileSystem`	`get(URI uri, Configuration conf)` Returns the FileSystem for this URI's scheme and authority.
`static FileSystem`	`get(URI uri, Configuration conf, String user)` Get a filesystem instance based on the uri, the passed configuration and the user
`static List<FileSystem.Statistics>`	`getAllStatistics()` Return the FileSystem classes that have Statistics
`long`	`getBlockSize(Path f)` Deprecated. Use getFileStatus() instead
`protected URI`	`getCanonicalUri()` Resolve the uri's hostname and add the default port if not in the uri
`ContentSummary`	`getContentSummary(Path f)` Return the `ContentSummary` of a given `Path`.
`long`	`getDefaultBlockSize()` Deprecated. use `getDefaultBlockSize(Path)` instead
`long`	`getDefaultBlockSize(Path f)` Return the number of bytes that large input files should be optimally be split into to minimize i/o time.
`protected int`	`getDefaultPort()` Get the default port for this file system.
`short`	`getDefaultReplication()` Deprecated. use `getDefaultReplication(Path)` instead
`short`	`getDefaultReplication(Path path)` Get the default replication for a path.
`static URI`	`getDefaultUri(Configuration conf)` Get the default filesystem URI from a configuration.
`BlockLocation[]`	`getFileBlockLocations(FileStatus file, long start, long len)` Return an array containing hostnames, offset and size of portions of the given file.
`BlockLocation[]`	`getFileBlockLocations(Path p, long start, long len)` Return an array containing hostnames, offset and size of portions of the given file.
`FileChecksum`	`getFileChecksum(Path f)` Get the checksum of a file.
`abstract FileStatus`	`getFileStatus(Path f)` Return a file status object that represents the path.
`static Class<? extends FileSystem>`	`getFileSystemClass(String scheme, Configuration conf)`
`Path`	`getHomeDirectory()` Return the current user's home directory in this filesystem.
`protected Path`	`getInitialWorkingDirectory()` Note: with the new FilesContext class, getWorkingDirectory() will be removed.
`long`	`getLength(Path f)` Deprecated. Use getFileStatus() instead
`static LocalFileSystem`	`getLocal(Configuration conf)` Get the local file system.
`String`	`getName()` Deprecated. call #getUri() instead.
`static FileSystem`	`getNamed(String name, Configuration conf)` Deprecated. call #get(URI,Configuration) instead.
`short`	`getReplication(Path src)` Deprecated. Use getFileStatus() instead
`String`	`getScheme()` Return the protocol scheme for the FileSystem.
`FsServerDefaults`	`getServerDefaults()` Deprecated. use `getServerDefaults(Path)` instead
`FsServerDefaults`	`getServerDefaults(Path p)` Return a set of server default configuration values
`static Map<String,FileSystem.Statistics>`	`getStatistics()` Deprecated. use `getAllStatistics()` instead
`static FileSystem.Statistics`	`getStatistics(String scheme, Class<? extends FileSystem> cls)` Get the statistics for a particular file system
`FsStatus`	`getStatus()` Returns a status object describing the use and capacity of the file system.
`FsStatus`	`getStatus(Path p)` Returns a status object describing the use and capacity of the file system.
`abstract URI`	`getUri()` Returns a URI whose scheme and authority identify this FileSystem.
`long`	`getUsed()` Return the total size of all files in the filesystem.
`abstract Path`	`getWorkingDirectory()` Get the current working directory for the given file system
`FileStatus[]`	`globStatus(Path pathPattern)` Return all the files that match filePattern and are not checksum files.
`FileStatus[]`	`globStatus(Path pathPattern, PathFilter filter)` Return an array of FileStatus objects whose path names match pathPattern and is accepted by the user-supplied path filter.
`void`	`initialize(URI name, Configuration conf)` Called after a new FileSystem instance is constructed.
`boolean`	`isDirectory(Path f)` True iff the named path is a directory.
`boolean`	`isFile(Path f)` True iff the named path is a regular file.
`RemoteIterator<Path>`	`listCorruptFileBlocks(Path path)`
`RemoteIterator<LocatedFileStatus>`	`listFiles(Path f, boolean recursive)` List the statuses and block locations of the files in the given path.
`RemoteIterator<LocatedFileStatus>`	`listLocatedStatus(Path f)` List the statuses of the files/directories in the given path if the path is a directory.
`protected RemoteIterator<LocatedFileStatus>`	`listLocatedStatus(Path f, PathFilter filter)` Listing a directory The returned results include its block location if it is a file The results are filtered by the given path filter
`abstract FileStatus[]`	`listStatus(Path f)` List the statuses of the files/directories in the given path if the path is a directory.
`FileStatus[]`	`listStatus(Path[] files)` Filter files/directories in the given list of paths using default path filter.
`FileStatus[]`	`listStatus(Path[] files, PathFilter filter)` Filter files/directories in the given list of paths using user-supplied path filter.
`FileStatus[]`	`listStatus(Path f, PathFilter filter)` Filter files/directories in the given path using the user-supplied path filter.
`Path`	`makeQualified(Path path)` Make sure that a path specifies a FileSystem.
`static boolean`	`mkdirs(FileSystem fs, Path dir, FsPermission permission)` create a directory with the provided permission The permission of the directory is set to be the provided permission as in setPermission, not permission&~umask
`boolean`	`mkdirs(Path f)` Call `mkdirs(Path, FsPermission)` with default permission.
`abstract boolean`	`mkdirs(Path f, FsPermission permission)` Make the given file and all non-existent parents into directories.
`void`	`moveFromLocalFile(Path[] srcs, Path dst)` The src files is on the local disk.
`void`	`moveFromLocalFile(Path src, Path dst)` The src file is on the local disk.
`void`	`moveToLocalFile(Path src, Path dst)` The src file is under FS, and the dst is on the local disk.
`static FileSystem`	`newInstance(Configuration conf)` Returns a unique configured filesystem implementation.
`static FileSystem`	`newInstance(URI uri, Configuration conf)` Returns the FileSystem for this URI's scheme and authority.
`static FileSystem`	`newInstance(URI uri, Configuration conf, String user)` Returns the FileSystem for this URI's scheme and authority and the passed user.
`static LocalFileSystem`	`newInstanceLocal(Configuration conf)` Get a unique local file system object
`FSDataInputStream`	`open(Path f)` Opens an FSDataInputStream at the indicated Path.
`abstract FSDataInputStream`	`open(Path f, int bufferSize)` Opens an FSDataInputStream at the indicated Path.
`protected FSDataOutputStream`	`primitiveCreate(Path f, FsPermission absolutePermission, EnumSet<CreateFlag> flag, int bufferSize, short replication, long blockSize, Progressable progress, Options.ChecksumOpt checksumOpt)` Deprecated.
`protected boolean`	`primitiveMkdir(Path f, FsPermission absolutePermission)` Deprecated.
`protected void`	`primitiveMkdir(Path f, FsPermission absolutePermission, boolean createParent)` Deprecated.
`static void`	`printStatistics()` Print all statistics for all file systems
`protected void`	`processDeleteOnExit()` Delete all files that were marked as delete-on-exit.
`abstract boolean`	`rename(Path src, Path dst)` Renames Path src to Path dst.
`protected void`	`rename(Path src, Path dst, Options.Rename... options)` Deprecated.
`Path`	`resolvePath(Path p)` Return the fully-qualified path of path f resolving the path through any symlinks or mount point
`static void`	`setDefaultUri(Configuration conf, String uri)` Set the default filesystem URI in a configuration.
`static void`	`setDefaultUri(Configuration conf, URI uri)` Set the default filesystem URI in a configuration.
`void`	`setOwner(Path p, String username, String groupname)` Set owner of a path (i.e.
`void`	`setPermission(Path p, FsPermission permission)` Set permission of a path.
`boolean`	`setReplication(Path src, short replication)` Set replication for an existing file.
`void`	`setTimes(Path p, long mtime, long atime)` Set access time of a file
`void`	`setVerifyChecksum(boolean verifyChecksum)` Set the verify checksum flag.
`abstract void`	`setWorkingDirectory(Path new_dir)` Set the current working directory for the given file system.
`void`	`setWriteChecksum(boolean writeChecksum)` Set the write checksum flag.
`Path`	`startLocalOutput(Path fsOutputFile, Path tmpLocalFile)` Returns a local File that the user can write output to.

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, toString, wait, wait, wait

- Field Detail
  - FS_DEFAULT_NAME_KEY
```
public static final String FS_DEFAULT_NAME_KEY
```
    See Also:
    Constant Field Values
  - DEFAULT_FS
```
public static final String DEFAULT_FS
```
    See Also:
    Constant Field Values
  - LOG
```
public static final org.apache.commons.logging.Log LOG
```
  - SHUTDOWN_HOOK_PRIORITY
```
public static final int SHUTDOWN_HOOK_PRIORITY
```
    Priority of the FileSystem shutdown hook.
    
    See Also:
    Constant Field Values
  - statistics
```
protected FileSystem.Statistics statistics
```
    The statistics for this file system.
- Constructor Detail
  - FileSystem
```
protected FileSystem()
```
- Method Detail
  - get
```
public static FileSystem get(URI uri,
             Configuration conf,
             String user)
                      throws IOException,
                             InterruptedException
```
    Get a filesystem instance based on the uri, the passed configuration and the user
    
    Parameters:
    uri - of the filesystem
    conf - the configuration to use
    user - to perform the get as
    
    Returns:
    the filesystem instance
    
    Throws:
    
    IOException
    
    InterruptedException
  - get
```
public static FileSystem get(Configuration conf)
                      throws IOException
```
    Returns the configured filesystem implementation.
    
    Parameters:
    conf - the configuration to use
    
    Throws:
    
    IOException
  - getDefaultUri
```
public static URI getDefaultUri(Configuration conf)
```
    Get the default filesystem URI from a configuration.
    
    Parameters:
    conf - the configuration to use
    
    Returns:
    the uri of the default filesystem
  - setDefaultUri
```
public static void setDefaultUri(Configuration conf,
                 URI uri)
```
    Set the default filesystem URI in a configuration.
    
    Parameters:
    conf - the configuration to alter
    uri - the new default filesystem uri
  - setDefaultUri
```
public static void setDefaultUri(Configuration conf,
                 String uri)
```
    Set the default filesystem URI in a configuration.
    
    Parameters:
    conf - the configuration to alter
    uri - the new default filesystem uri
  - initialize
```
public void initialize(URI name,
              Configuration conf)
                throws IOException
```
    Called after a new FileSystem instance is constructed.
    
    Parameters:
    name - a uri whose authority section names the host, port, etc. for this FileSystem
    conf - the configuration
    
    Throws:
    
    IOException
  - getScheme
```
public String getScheme()
```
    Return the protocol scheme for the FileSystem.
    This implementation throws an UnsupportedOperationException.
    
    Returns:
    the protocol scheme for the FileSystem.
  - getUri
```
public abstract URI getUri()
```
    Returns a URI whose scheme and authority identify this FileSystem.
  - getCanonicalUri
```
protected URI getCanonicalUri()
```
    Resolve the uri's hostname and add the default port if not in the uri
    
    Returns:
    URI
    See Also:
    NetUtils.getCanonicalUri(URI, int)
  - getDefaultPort
```
protected int getDefaultPort()
```
    Get the default port for this file system.
    
    Returns:
    the default port or 0 if there isn't one
  - getName
```
@Deprecated
public String getName()
```
    Deprecated. call #getUri() instead.
  - getNamed
```
@Deprecated
public static FileSystem getNamed(String name,
                             Configuration conf)
                           throws IOException
```
    Deprecated. call #get(URI,Configuration) instead.
    
    Throws:
    
    IOException
  - getLocal
```
public static LocalFileSystem getLocal(Configuration conf)
                                throws IOException
```
    Get the local file system.
    
    Parameters:
    conf - the configuration to configure the file system with
    
    Returns:
    a LocalFileSystem
    
    Throws:
    
    IOException
  - get
```
public static FileSystem get(URI uri,
             Configuration conf)
                      throws IOException
```
    Returns the FileSystem for this URI's scheme and authority. The scheme of the URI determines a configuration property name, fs.scheme.class whose value names the FileSystem class. The entire URI is passed to the FileSystem instance's initialize method.
    
    Throws:
    
    IOException
  - newInstance
```
public static FileSystem newInstance(URI uri,
                     Configuration conf,
                     String user)
                              throws IOException,
                                     InterruptedException
```
    Returns the FileSystem for this URI's scheme and authority and the passed user. Internally invokes newInstance(URI, Configuration)
    
    Parameters:
    uri - of the filesystem
    conf - the configuration to use
    user - to perform the get as
    
    Returns:
    filesystem instance
    
    Throws:
    
    IOException
    
    InterruptedException
  - newInstance
```
public static FileSystem newInstance(URI uri,
                     Configuration conf)
                              throws IOException
```
    Returns the FileSystem for this URI's scheme and authority. The scheme of the URI determines a configuration property name, fs.scheme.class whose value names the FileSystem class. The entire URI is passed to the FileSystem instance's initialize method. This always returns a new FileSystem object.
    
    Throws:
    
    IOException
  - newInstance
```
public static FileSystem newInstance(Configuration conf)
                              throws IOException
```
    Returns a unique configured filesystem implementation. This always returns a new FileSystem object.
    
    Parameters:
    conf - the configuration to use
    
    Throws:
    
    IOException
  - newInstanceLocal
```
public static LocalFileSystem newInstanceLocal(Configuration conf)
                                        throws IOException
```
    Get a unique local file system object
    
    Parameters:
    conf - the configuration to configure the file system with
    
    Returns:
    a LocalFileSystem This always returns a new FileSystem object.
    
    Throws:
    
    IOException
  - closeAll
```
public static void closeAll()
                     throws IOException
```
    Close all cached filesystems. Be sure those filesystems are not used anymore.
    
    Throws:
    
    IOException
  - closeAllForUGI
```
public static void closeAllForUGI(org.apache.hadoop.security.UserGroupInformation ugi)
                           throws IOException
```
    Close all cached filesystems for a given UGI. Be sure those filesystems are not used anymore.
    
    Parameters:
    ugi - user group info to close
    
    Throws:
    
    IOException
  - makeQualified
```
public Path makeQualified(Path path)
```
    Make sure that a path specifies a FileSystem.
    
    Parameters:
    path - to use
  - create
```
public static FSDataOutputStream create(FileSystem fs,
                        Path file,
                        FsPermission permission)
                                 throws IOException
```
    create a file with the provided permission The permission of the file is set to be the provided permission as in setPermission, not permission&~umask It is implemented using two RPCs. It is understood that it is inefficient, but the implementation is thread-safe. The other option is to change the value of umask in configuration to be 0, but it is not thread-safe.
    
    Parameters:
    fs - file system handle
    file - the name of the file to be created
    permission - the permission of the file
    
    Returns:
    an output stream
    
    Throws:
    
    IOException
  - mkdirs
```
public static boolean mkdirs(FileSystem fs,
             Path dir,
             FsPermission permission)
                      throws IOException
```
    create a directory with the provided permission The permission of the directory is set to be the provided permission as in setPermission, not permission&~umask
    
    Parameters:
    fs - file system handle
    dir - the name of the directory to be created
    permission - the permission of the directory
    
    Returns:
    true if the directory creation succeeds; false otherwise
    
    Throws:
    
    IOException
    See Also:
    create(FileSystem, Path, FsPermission)
  - checkPath
```
protected void checkPath(Path path)
```
    Check that a Path belongs to this FileSystem.
    
    Parameters:
    path - to check
  - getFileBlockLocations
```
public BlockLocation[] getFileBlockLocations(FileStatus file,
                                    long start,
                                    long len)
                                      throws IOException
```
    Return an array containing hostnames, offset and size of portions of the given file. For a nonexistent file or regions, null will be returned. This call is most helpful with DFS, where it returns hostnames of machines that contain the given file. The FileSystem will simply return an elt containing 'localhost'.
    
    Parameters:
    file - FilesStatus to get data from
    start - offset into the given file
    len - length for which to get locations for
    
    Throws:
    
    IOException
  - getFileBlockLocations
```
public BlockLocation[] getFileBlockLocations(Path p,
                                    long start,
                                    long len)
                                      throws IOException
```
    Return an array containing hostnames, offset and size of portions of the given file. For a nonexistent file or regions, null will be returned. This call is most helpful with DFS, where it returns hostnames of machines that contain the given file. The FileSystem will simply return an elt containing 'localhost'.
    
    Parameters:
    p - path is used to identify an FS since an FS could have another FS that it could be delegating the call to
    start - offset into the given file
    len - length for which to get locations for
    
    Throws:
    
    IOException
  - getServerDefaults
```
@Deprecated
public FsServerDefaults getServerDefaults()
                                   throws IOException
```
    Deprecated. use getServerDefaults(Path) instead
    
    Return a set of server default configuration values
    
    Returns:
    server default configuration values
    
    Throws:
    
    IOException
  - getServerDefaults
```
public FsServerDefaults getServerDefaults(Path p)
                                   throws IOException
```
    Return a set of server default configuration values
    
    Parameters:
    p - path is used to identify an FS since an FS could have another FS that it could be delegating the call to
    
    Returns:
    server default configuration values
    
    Throws:
    
    IOException
  - resolvePath
```
public Path resolvePath(Path p)
                 throws IOException
```
    Return the fully-qualified path of path f resolving the path through any symlinks or mount point
    
    Parameters:
    p - path to be resolved
    
    Returns:
    fully qualified path
    
    Throws:
    
    FileNotFoundException
    
    IOException
  - open
```
public abstract FSDataInputStream open(Path f,
                     int bufferSize)
                                throws IOException
```
    Opens an FSDataInputStream at the indicated Path.
    
    Parameters:
    f - the file name to open
    bufferSize - the size of the buffer to be used.
    
    Throws:
    
    IOException
  - open
```
public FSDataInputStream open(Path f)
                       throws IOException
```
    Opens an FSDataInputStream at the indicated Path.
    
    Parameters:
    f - the file to open
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path. Files are overwritten by default.
    
    Parameters:
    f - the file to create
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        boolean overwrite)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path.
    
    Parameters:
    f - the file to create
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an exception will be thrown.
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        Progressable progress)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path with write-progress reporting. Files are overwritten by default.
    
    Parameters:
    f - the file to create
    progress - to report progress
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        short replication)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path. Files are overwritten by default.
    
    Parameters:
    f - the file to create
    replication - the replication factor
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        short replication,
                        Progressable progress)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path with write-progress reporting. Files are overwritten by default.
    
    Parameters:
    f - the file to create
    replication - the replication factor
    progress - to report progress
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        boolean overwrite,
                        int bufferSize)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path.
    
    Parameters:
    f - the file name to create
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        boolean overwrite,
                        int bufferSize,
                        Progressable progress)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path with write-progress reporting.
    
    Parameters:
    f - the path of the file to open
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        boolean overwrite,
                        int bufferSize,
                        short replication,
                        long blockSize)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path.
    
    Parameters:
    f - the file name to open
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    
    Throws:
    
    IOException
  - create
```
public FSDataOutputStream create(Path f,
                        boolean overwrite,
                        int bufferSize,
                        short replication,
                        long blockSize,
                        Progressable progress)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path with write-progress reporting.
    
    Parameters:
    f - the file name to open
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    
    Throws:
    
    IOException
  - create
```
public abstract FSDataOutputStream create(Path f,
                        FsPermission permission,
                        boolean overwrite,
                        int bufferSize,
                        short replication,
                        long blockSize,
                        Progressable progress)
                                   throws IOException
```
    Create an FSDataOutputStream at the indicated Path with write-progress reporting.
    
    Parameters:
    f - the file name to open
    permission -
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    blockSize -
    progress -
    
    Throws:
    
    IOException
    See Also:
    setPermission(Path, FsPermission)
  - create
```
public FSDataOutputStream create(Path f,
                        FsPermission permission,
                        EnumSet<CreateFlag> flags,
                        int bufferSize,
                        short replication,
                        long blockSize,
                        Progressable progress)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path with write-progress reporting.
    
    Parameters:
    f - the file name to open
    permission -
    flags - CreateFlags to use for this stream.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    blockSize -
    progress -
    
    Throws:
    
    IOException
    See Also:
    setPermission(Path, FsPermission)
  - create
```
public FSDataOutputStream create(Path f,
                        FsPermission permission,
                        EnumSet<CreateFlag> flags,
                        int bufferSize,
                        short replication,
                        long blockSize,
                        Progressable progress,
                        Options.ChecksumOpt checksumOpt)
                          throws IOException
```
    Create an FSDataOutputStream at the indicated Path with a custom checksum option
    
    Parameters:
    f - the file name to open
    permission -
    flags - CreateFlags to use for this stream.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    blockSize -
    progress -
    checksumOpt - checksum parameter. If null, the values found in conf will be used.
    
    Throws:
    
    IOException
    See Also:
    setPermission(Path, FsPermission)
  - primitiveCreate
```
@Deprecated
protected FSDataOutputStream primitiveCreate(Path f,
                                            FsPermission absolutePermission,
                                            EnumSet<CreateFlag> flag,
                                            int bufferSize,
                                            short replication,
                                            long blockSize,
                                            Progressable progress,
                                            Options.ChecksumOpt checksumOpt)
                                      throws IOException
```
    Deprecated.
    
    Throws:
    
    IOException
  - primitiveMkdir
```
@Deprecated
protected boolean primitiveMkdir(Path f,
                                FsPermission absolutePermission)
                          throws IOException
```
    Deprecated.
    
    This version of the mkdirs method assumes that the permission is absolute. It has been added to support the FileContext that processes the permission with umask before calling this method. This a temporary method added to support the transition from FileSystem to FileContext for user applications.
    
    Throws:
    
    IOException
  - primitiveMkdir
```
@Deprecated
protected void primitiveMkdir(Path f,
                             FsPermission absolutePermission,
                             boolean createParent)
                       throws IOException
```
    Deprecated.
    
    This version of the mkdirs method assumes that the permission is absolute. It has been added to support the FileContext that processes the permission with umask before calling this method. This a temporary method added to support the transition from FileSystem to FileContext for user applications.
    
    Throws:
    
    IOException
  - createNonRecursive
```
@Deprecated
public FSDataOutputStream createNonRecursive(Path f,
                                               boolean overwrite,
                                               int bufferSize,
                                               short replication,
                                               long blockSize,
                                               Progressable progress)
                                      throws IOException
```
    Deprecated. API only for 0.20-append
    
    Opens an FSDataOutputStream at the indicated Path with write-progress reporting. Same as create(), except fails if parent directory doesn't already exist.
    
    Parameters:
    f - the file name to open
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    blockSize -
    progress -
    
    Throws:
    
    IOException
    See Also:
    setPermission(Path, FsPermission)
  - createNonRecursive
```
@Deprecated
public FSDataOutputStream createNonRecursive(Path f,
                                               FsPermission permission,
                                               boolean overwrite,
                                               int bufferSize,
                                               short replication,
                                               long blockSize,
                                               Progressable progress)
                                      throws IOException
```
    Deprecated. API only for 0.20-append
    
    Opens an FSDataOutputStream at the indicated Path with write-progress reporting. Same as create(), except fails if parent directory doesn't already exist.
    
    Parameters:
    f - the file name to open
    permission -
    overwrite - if a file with this name already exists, then if true, the file will be overwritten, and if false an error will be thrown.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    blockSize -
    progress -
    
    Throws:
    
    IOException
    See Also:
    setPermission(Path, FsPermission)
  - createNonRecursive
```
@Deprecated
public FSDataOutputStream createNonRecursive(Path f,
                                               FsPermission permission,
                                               EnumSet<CreateFlag> flags,
                                               int bufferSize,
                                               short replication,
                                               long blockSize,
                                               Progressable progress)
                                      throws IOException
```
    Deprecated. API only for 0.20-append
    
    Opens an FSDataOutputStream at the indicated Path with write-progress reporting. Same as create(), except fails if parent directory doesn't already exist.
    
    Parameters:
    f - the file name to open
    permission -
    flags - CreateFlags to use for this stream.
    bufferSize - the size of the buffer to be used.
    replication - required block replication for the file.
    blockSize -
    progress -
    
    Throws:
    
    IOException
    See Also:
    setPermission(Path, FsPermission)
  - createNewFile
```
public boolean createNewFile(Path f)
                      throws IOException
```
    Creates the given Path as a brand-new zero-length file. If create fails, or if it already existed, return false.
    
    Parameters:
    f - path to use for create
    
    Throws:
    
    IOException
  - append
```
public FSDataOutputStream append(Path f)
                          throws IOException
```
    Append to an existing file (optional operation). Same as append(f, getConf().getInt("io.file.buffer.size", 4096), null)
    
    Parameters:
    f - the existing file to be appended.
    
    Throws:
    
    IOException
  - append
```
public FSDataOutputStream append(Path f,
                        int bufferSize)
                          throws IOException
```
    Append to an existing file (optional operation). Same as append(f, bufferSize, null).
    
    Parameters:
    f - the existing file to be appended.
    bufferSize - the size of the buffer to be used.
    
    Throws:
    
    IOException
  - append
```
public abstract FSDataOutputStream append(Path f,
                        int bufferSize,
                        Progressable progress)
                                   throws IOException
```
    Append to an existing file (optional operation).
    
    Parameters:
    f - the existing file to be appended.
    bufferSize - the size of the buffer to be used.
    progress - for reporting progress if it is not null.
    
    Throws:
    
    IOException
  - concat
```
public void concat(Path trg,
          Path[] psrcs)
            throws IOException
```
    Concat existing files together.
    
    Parameters:
    trg - the path to the target destination.
    psrcs - the paths to the sources to use for the concatenation.
    
    Throws:
    
    IOException
  - getReplication
```
@Deprecated
public short getReplication(Path src)
                     throws IOException
```
    Deprecated. Use getFileStatus() instead
    
    Get replication.
    
    Parameters:
    src - file name
    
    Returns:
    file replication
    
    Throws:
    
    IOException
  - setReplication
```
public boolean setReplication(Path src,
                     short replication)
                       throws IOException
```
    Set replication for an existing file.
    
    Parameters:
    src - file name
    replication - new replication
    
    Returns:
    true if successful; false if file does not exist or is a directory
    
    Throws:
    
    IOException
  - rename
```
public abstract boolean rename(Path src,
             Path dst)
                        throws IOException
```
    Renames Path src to Path dst. Can take place on local fs or remote DFS.
    
    Parameters:
    src - path to be renamed
    dst - new path after rename
    
    Returns:
    true if rename is successful
    
    Throws:
    
    IOException - on failure
  - rename
```
@Deprecated
protected void rename(Path src,
                     Path dst,
                     Options.Rename... options)
               throws IOException
```
    Deprecated.
    Renames Path src to Path dst
    - Fails if src is a file and dst is a directory.
    - Fails if src is a directory and dst is a file.
    - Fails if the parent of dst does not exist or is a file.
    If OVERWRITE option is not passed as an argument, rename fails if the dst already exists.
    If OVERWRITE option is passed as an argument, rename overwrites the dst if it is a file or an empty directory. Rename fails if dst is a non-empty directory.
    Note that atomicity of rename is dependent on the file system implementation. Please refer to the file system documentation for details. This default implementation is non atomic.
    This method is deprecated since it is a temporary method added to support the transition from FileSystem to FileContext for user applications.
    Parameters:
    src - path to be renamed
    dst - new path after rename
    
    Throws:
    
    IOException - on failure
  - delete
```
@Deprecated
public boolean delete(Path f)
               throws IOException
```
    Deprecated. Use delete(Path, boolean) instead.
    
    Delete a file
    
    Throws:
    
    IOException
  - delete
```
public abstract boolean delete(Path f,
             boolean recursive)
                        throws IOException
```
    Delete a file.
    
    Parameters:
    f - the path to delete.
    recursive - if path is a directory and set to true, the directory is deleted else throws an exception. In case of a file the recursive can be set to either true or false.
    
    Returns:
    true if delete is successful else false.
    
    Throws:
    
    IOException
  - deleteOnExit
```
public boolean deleteOnExit(Path f)
                     throws IOException
```
    Mark a path to be deleted when FileSystem is closed. When the JVM shuts down, all FileSystem objects will be closed automatically. Then, the marked path will be deleted as a result of closing the FileSystem. The path has to exist in the file system.
    
    Parameters:
    f - the path to delete.
    
    Returns:
    true if deleteOnExit is successful, otherwise false.
    
    Throws:
    
    IOException
  - cancelDeleteOnExit
```
public boolean cancelDeleteOnExit(Path f)
```
    Cancel the deletion of the path when the FileSystem is closed
    
    Parameters:
    f - the path to cancel deletion
  - processDeleteOnExit
```
protected void processDeleteOnExit()
```
    Delete all files that were marked as delete-on-exit. This recursively deletes all files in the specified paths.
  - exists
```
public boolean exists(Path f)
               throws IOException
```
    Check if exists.
    
    Parameters:
    f - source file
    
    Throws:
    
    IOException
  - isDirectory
```
public boolean isDirectory(Path f)
                    throws IOException
```
    True iff the named path is a directory. Note: Avoid using this method. Instead reuse the FileStatus returned by getFileStatus() or listStatus() methods.
    
    Parameters:
    f - path to check
    
    Throws:
    
    IOException
  - isFile
```
public boolean isFile(Path f)
               throws IOException
```
    True iff the named path is a regular file. Note: Avoid using this method. Instead reuse the FileStatus returned by getFileStatus() or listStatus() methods.
    
    Parameters:
    f - path to check
    
    Throws:
    
    IOException
  - getLength
```
@Deprecated
public long getLength(Path f)
               throws IOException
```
    Deprecated. Use getFileStatus() instead
    
    Throws:
    
    IOException
  - getContentSummary
```
public ContentSummary getContentSummary(Path f)
                                 throws IOException
```
    Return the ContentSummary of a given Path.
    
    Parameters:
    f - path to use
    
    Throws:
    
    IOException
  - listStatus
```
public abstract FileStatus[] listStatus(Path f)
                                 throws FileNotFoundException,
                                        IOException
```
    List the statuses of the files/directories in the given path if the path is a directory.
    
    Parameters:
    f - given path
    
    Returns:
    the statuses of the files/directories in the given patch
    
    Throws:
    
    FileNotFoundException - when the path does not exist; IOException see specific implementation
    
    IOException
  - listCorruptFileBlocks
```
public RemoteIterator<Path> listCorruptFileBlocks(Path path)
                                           throws IOException
```
    Returns:
    an iterator over the corrupt files under the given path (may contain duplicates if a file has more than one corrupt block)
    
    Throws:
    
    IOException
  - listStatus
```
public FileStatus[] listStatus(Path f,
                      PathFilter filter)
                        throws FileNotFoundException,
                               IOException
```
    Filter files/directories in the given path using the user-supplied path filter.
    
    Parameters:
    f - a path name
    filter - the user-supplied path filter
    
    Returns:
    an array of FileStatus objects for the files under the given path after applying the filter
    
    Throws:
    
    FileNotFoundException - when the path does not exist; IOException see specific implementation
    
    IOException
  - listStatus
```
public FileStatus[] listStatus(Path[] files)
                        throws FileNotFoundException,
                               IOException
```
    Filter files/directories in the given list of paths using default path filter.
    
    Parameters:
    files - a list of paths
    
    Returns:
    a list of statuses for the files under the given paths after applying the filter default Path filter
    
    Throws:
    
    FileNotFoundException - when the path does not exist; IOException see specific implementation
    
    IOException
  - listStatus
```
public FileStatus[] listStatus(Path[] files,
                      PathFilter filter)
                        throws FileNotFoundException,
                               IOException
```
    Filter files/directories in the given list of paths using user-supplied path filter.
    
    Parameters:
    files - a list of paths
    filter - the user-supplied path filter
    
    Returns:
    a list of statuses for the files under the given paths after applying the filter
    
    Throws:
    
    FileNotFoundException - when the path does not exist; IOException see specific implementation
    
    IOException
  - globStatus
```
public FileStatus[] globStatus(Path pathPattern)
                        throws IOException
```
    Return all the files that match filePattern and are not checksum files. Results are sorted by their names.
    A filename pattern is composed of regular characters and special pattern matching characters, which are:
    
    ?
    Matches any single character.
    
    *
    Matches zero or more characters.
    
    [abc]
    Matches a single character from character set {a,b,c}.
    
    [a-b]
    Matches a single character from the character range {a...b}. Note that character a must be lexicographically less than or equal to character b.
    
    [^a]
    Matches a single character that is not from character set or range {a}. Note that the ^ character must occur immediately to the right of the opening bracket.
    
    \c
    Removes (escapes) any special meaning of character c.
    
    {ab,cd}
    Matches a string from the string set {ab, cd}
    
    {ab,c{de,fh}}
    Matches a string from the string set {ab, cde, cfh}
    
    Parameters:
    pathPattern - a regular expression specifying a pth pattern
    
    Returns:
    an array of paths that match the path pattern
    
    Throws:
    
    IOException
  - globStatus
```
public FileStatus[] globStatus(Path pathPattern,
                      PathFilter filter)
                        throws IOException
```
    Return an array of FileStatus objects whose path names match pathPattern and is accepted by the user-supplied path filter. Results are sorted by their path names. Return null if pathPattern has no glob and the path does not exist. Return an empty array if pathPattern has a glob and no path matches it.
    
    Parameters:
    pathPattern - a regular expression specifying the path pattern
    filter - a user-supplied path filter
    
    Returns:
    an array of FileStatus objects
    
    Throws:
    
    IOException - if any I/O error occurs when fetching file status
  - listLocatedStatus
```
public RemoteIterator<LocatedFileStatus> listLocatedStatus(Path f)
                                                    throws FileNotFoundException,
                                                           IOException
```
    List the statuses of the files/directories in the given path if the path is a directory. Return the file's status and block locations If the path is a file. If a returned status is a file, it contains the file's block locations.
    
    Parameters:
    f - is the path
    
    Returns:
    an iterator that traverses statuses of the files/directories in the given path
    
    Throws:
    
    FileNotFoundException - If f does not exist
    
    IOException - If an I/O error occurred
  - listLocatedStatus
```
protected RemoteIterator<LocatedFileStatus> listLocatedStatus(Path f,
                                                  PathFilter filter)
                                                       throws FileNotFoundException,
                                                              IOException
```
    Listing a directory The returned results include its block location if it is a file The results are filtered by the given path filter
    
    Parameters:
    f - a path
    filter - a path filter
    
    Returns:
    an iterator that traverses statuses of the files/directories in the given path
    
    Throws:
    
    FileNotFoundException - if f does not exist
    
    IOException - if any I/O error occurred
  - listFiles
```
public RemoteIterator<LocatedFileStatus> listFiles(Path f,
                                          boolean recursive)
                                            throws FileNotFoundException,
                                                   IOException
```
    List the statuses and block locations of the files in the given path. If the path is a directory, if recursive is false, returns files in the directory; if recursive is true, return files in the subtree rooted at the path. If the path is a file, return the file's status and block locations.
    
    Parameters:
    f - is the path
    recursive - if the subdirectories need to be traversed recursively
    
    Returns:
    an iterator that traverses statuses of the files
    
    Throws:
    
    FileNotFoundException - when the path does not exist; IOException see specific implementation
    
    IOException
  - getHomeDirectory
```
public Path getHomeDirectory()
```
    Return the current user's home directory in this filesystem. The default implementation returns "/user/$USER/".
  - setWorkingDirectory
```
public abstract void setWorkingDirectory(Path new_dir)
```
    Set the current working directory for the given file system. All relative paths will be resolved relative to it.
    
    Parameters:
    new_dir -
  - getWorkingDirectory
```
public abstract Path getWorkingDirectory()
```
    Get the current working directory for the given file system
    
    Returns:
    the directory pathname
  - getInitialWorkingDirectory
```
protected Path getInitialWorkingDirectory()
```
    Note: with the new FilesContext class, getWorkingDirectory() will be removed. The working directory is implemented in FilesContext. Some file systems like LocalFileSystem have an initial workingDir that we use as the starting workingDir. For other file systems like HDFS there is no built in notion of an initial workingDir.
    
    Returns:
    if there is built in notion of workingDir then it is returned; else a null is returned.
  - mkdirs
```
public boolean mkdirs(Path f)
               throws IOException
```
    Call mkdirs(Path, FsPermission) with default permission.
    
    Throws:
    
    IOException
  - mkdirs
```
public abstract boolean mkdirs(Path f,
             FsPermission permission)
                        throws IOException
```
    Make the given file and all non-existent parents into directories. Has the semantics of Unix 'mkdir -p'. Existence of the directory hierarchy is not an error.
    
    Parameters:
    f - path to create
    permission - to apply to f
    
    Throws:
    
    IOException
  - copyFromLocalFile
```
public void copyFromLocalFile(Path src,
                     Path dst)
                       throws IOException
```
    The src file is on the local disk. Add it to FS at the given dst name and the source is kept intact afterwards
    
    Parameters:
    src - path
    dst - path
    
    Throws:
    
    IOException
  - moveFromLocalFile
```
public void moveFromLocalFile(Path[] srcs,
                     Path dst)
                       throws IOException
```
    The src files is on the local disk. Add it to FS at the given dst name, removing the source afterwards.
    
    Parameters:
    srcs - path
    dst - path
    
    Throws:
    
    IOException
  - moveFromLocalFile
```
public void moveFromLocalFile(Path src,
                     Path dst)
                       throws IOException
```
    The src file is on the local disk. Add it to FS at the given dst name, removing the source afterwards.
    
    Parameters:
    src - path
    dst - path
    
    Throws:
    
    IOException
  - copyFromLocalFile
```
public void copyFromLocalFile(boolean delSrc,
                     Path src,
                     Path dst)
                       throws IOException
```
    The src file is on the local disk. Add it to FS at the given dst name. delSrc indicates if the source should be removed
    
    Parameters:
    delSrc - whether to delete the src
    src - path
    dst - path
    
    Throws:
    
    IOException
  - copyFromLocalFile
```
public void copyFromLocalFile(boolean delSrc,
                     boolean overwrite,
                     Path[] srcs,
                     Path dst)
                       throws IOException
```
    The src files are on the local disk. Add it to FS at the given dst name. delSrc indicates if the source should be removed
    
    Parameters:
    delSrc - whether to delete the src
    overwrite - whether to overwrite an existing file
    srcs - array of paths which are source
    dst - path
    
    Throws:
    
    IOException
  - copyFromLocalFile
```
public void copyFromLocalFile(boolean delSrc,
                     boolean overwrite,
                     Path src,
                     Path dst)
                       throws IOException
```
    The src file is on the local disk. Add it to FS at the given dst name. delSrc indicates if the source should be removed
    
    Parameters:
    delSrc - whether to delete the src
    overwrite - whether to overwrite an existing file
    src - path
    dst - path
    
    Throws:
    
    IOException
  - copyToLocalFile
```
public void copyToLocalFile(Path src,
                   Path dst)
                     throws IOException
```
    The src file is under FS, and the dst is on the local disk. Copy it from FS control to the local dst name.
    
    Parameters:
    src - path
    dst - path
    
    Throws:
    
    IOException
  - moveToLocalFile
```
public void moveToLocalFile(Path src,
                   Path dst)
                     throws IOException
```
    The src file is under FS, and the dst is on the local disk. Copy it from FS control to the local dst name. Remove the source afterwards
    
    Parameters:
    src - path
    dst - path
    
    Throws:
    
    IOException
  - copyToLocalFile
```
public void copyToLocalFile(boolean delSrc,
                   Path src,
                   Path dst)
                     throws IOException
```
    The src file is under FS, and the dst is on the local disk. Copy it from FS control to the local dst name. delSrc indicates if the src will be removed or not.
    
    Parameters:
    delSrc - whether to delete the src
    src - path
    dst - path
    
    Throws:
    
    IOException
  - copyToLocalFile
```
public void copyToLocalFile(boolean delSrc,
                   Path src,
                   Path dst,
                   boolean useRawLocalFileSystem)
                     throws IOException
```
    The src file is under FS, and the dst is on the local disk. Copy it from FS control to the local dst name. delSrc indicates if the src will be removed or not. useRawLocalFileSystem indicates whether to use RawLocalFileSystem as local file system or not. RawLocalFileSystem is non crc file system.So, It will not create any crc files at local.
    
    Parameters:
    delSrc - whether to delete the src
    src - path
    dst - path
    useRawLocalFileSystem - whether to use RawLocalFileSystem as local file system or not.
    
    Throws:
    
    IOException - - if any IO error
  - startLocalOutput
```
public Path startLocalOutput(Path fsOutputFile,
                    Path tmpLocalFile)
                      throws IOException
```
    Returns a local File that the user can write output to. The caller provides both the eventual FS target name and the local working file. If the FS is local, we write directly into the target. If the FS is remote, we write into the tmp local area.
    
    Parameters:
    fsOutputFile - path of output file
    tmpLocalFile - path of local tmp file
    
    Throws:
    
    IOException
  - completeLocalOutput
```
public void completeLocalOutput(Path fsOutputFile,
                       Path tmpLocalFile)
                         throws IOException
```
    Called when we're all done writing to the target. A local FS will do nothing, because we've written to exactly the right place. A remote FS will copy the contents of tmpLocalFile to the correct target at fsOutputFile.
    
    Parameters:
    fsOutputFile - path of output file
    tmpLocalFile - path to local tmp file
    
    Throws:
    
    IOException
  - close
```
public void close()
           throws IOException
```
    No more filesystem operations are needed. Will release any held locks.
    
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Throws:
    
    IOException
  - getUsed
```
public long getUsed()
             throws IOException
```
    Return the total size of all files in the filesystem.
    
    Throws:
    
    IOException
  - getBlockSize
```
@Deprecated
public long getBlockSize(Path f)
                  throws IOException
```
    Deprecated. Use getFileStatus() instead
    
    Throws:
    
    IOException
  - getDefaultBlockSize
```
@Deprecated
public long getDefaultBlockSize()
```
    Deprecated. use getDefaultBlockSize(Path) instead
    
    Return the number of bytes that large input files should be optimally be split into to minimize i/o time.
  - getDefaultBlockSize
```
public long getDefaultBlockSize(Path f)
```
    Return the number of bytes that large input files should be optimally be split into to minimize i/o time. The given path will be used to locate the actual filesystem. The full path does not have to exist.
    
    Parameters:
    f - path of file
    
    Returns:
    the default block size for the path's filesystem
  - getDefaultReplication
```
@Deprecated
public short getDefaultReplication()
```
    Deprecated. use getDefaultReplication(Path) instead
    
    Get the default replication.
  - getDefaultReplication
```
public short getDefaultReplication(Path path)
```
    Get the default replication for a path. The given path will be used to locate the actual filesystem. The full path does not have to exist.
    
    Parameters:
    path - of the file
    
    Returns:
    default replication for the path's filesystem
  - getFileStatus
```
public abstract FileStatus getFileStatus(Path f)
                                  throws IOException
```
    Return a file status object that represents the path.
    
    Parameters:
    f - The path we want information from
    
    Returns:
    a FileStatus object
    
    Throws:
    
    FileNotFoundException - when the path does not exist; IOException see specific implementation
    
    IOException
  - getFileChecksum
```
public FileChecksum getFileChecksum(Path f)
                             throws IOException
```
    Get the checksum of a file.
    
    Parameters:
    f - The file path
    
    Returns:
    The file checksum. The default return value is null, which indicates that no checksum algorithm is implemented in the corresponding FileSystem.
    
    Throws:
    
    IOException
  - setVerifyChecksum
```
public void setVerifyChecksum(boolean verifyChecksum)
```
    Set the verify checksum flag. This is only applicable if the corresponding FileSystem supports checksum. By default doesn't do anything.
    
    Parameters:
    verifyChecksum -
  - setWriteChecksum
```
public void setWriteChecksum(boolean writeChecksum)
```
    Set the write checksum flag. This is only applicable if the corresponding FileSystem supports checksum. By default doesn't do anything.
    
    Parameters:
    writeChecksum -
  - getStatus
```
public FsStatus getStatus()
                   throws IOException
```
    Returns a status object describing the use and capacity of the file system. If the file system has multiple partitions, the use and capacity of the root partition is reflected.
    
    Returns:
    a FsStatus object
    
    Throws:
    
    IOException - see specific implementation
  - getStatus
```
public FsStatus getStatus(Path p)
                   throws IOException
```
    Returns a status object describing the use and capacity of the file system. If the file system has multiple partitions, the use and capacity of the partition pointed to by the specified path is reflected.
    
    Parameters:
    p - Path for which status should be obtained. null means the default partition.
    
    Returns:
    a FsStatus object
    
    Throws:
    
    IOException - see specific implementation
  - setPermission
```
public void setPermission(Path p,
                 FsPermission permission)
                   throws IOException
```
    Set permission of a path.
    
    Parameters:
    p -
    permission -
    
    Throws:
    
    IOException
  - setOwner
```
public void setOwner(Path p,
            String username,
            String groupname)
              throws IOException
```
    Set owner of a path (i.e. a file or a directory). The parameters username and groupname cannot both be null.
    
    Parameters:
    p - The path
    username - If it is null, the original username remains unchanged.
    groupname - If it is null, the original groupname remains unchanged.
    
    Throws:
    
    IOException
  - setTimes
```
public void setTimes(Path p,
            long mtime,
            long atime)
              throws IOException
```
    Set access time of a file
    
    Parameters:
    p - The path
    mtime - Set the modification time of this file. The number of milliseconds since Jan 1, 1970. A value of -1 means that this call should not set modification time.
    atime - Set the access time of this file. The number of milliseconds since Jan 1, 1970. A value of -1 means that this call should not set access time.
    
    Throws:
    
    IOException
  - getFileSystemClass
```
public static Class<? extends FileSystem> getFileSystemClass(String scheme,
                                             Configuration conf)
                                                      throws IOException
```
    Throws:
    
    IOException
  - getStatistics
```
@Deprecated
public static Map<String,FileSystem.Statistics> getStatistics()
```
    Deprecated. use getAllStatistics() instead
    
    Get the Map of Statistics object indexed by URI Scheme.
    
    Returns:
    a Map having a key as URI scheme and value as Statistics object
  - getAllStatistics
```
public static List<FileSystem.Statistics> getAllStatistics()
```
    Return the FileSystem classes that have Statistics
  - getStatistics
```
public static FileSystem.Statistics getStatistics(String scheme,
                                  Class<? extends FileSystem> cls)
```
    Get the statistics for a particular file system
    
    Parameters:
    cls - the class to lookup
    
    Returns:
    a statistics object
  - clearStatistics
```
public static void clearStatistics()
```
    Reset all statistics for all file systems
  - printStatistics
```
public static void printStatistics()
                            throws IOException
```
    Print all statistics for all file systems
    
    Throws:
    
    IOException

Class FileSystem

Nested Class Summary

Field Summary

Constructor Summary

Method Summary

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

Methods inherited from class java.lang.Object

Field Detail

FS_DEFAULT_NAME_KEY

DEFAULT_FS

LOG

SHUTDOWN_HOOK_PRIORITY

statistics

Constructor Detail

FileSystem

Method Detail

get

get

getDefaultUri

setDefaultUri

setDefaultUri

initialize

getScheme

getUri

getCanonicalUri

getDefaultPort

getName

getNamed

getLocal

get

newInstance

newInstance

newInstance

newInstanceLocal

closeAll

closeAllForUGI

makeQualified

create

mkdirs

checkPath

getFileBlockLocations

getFileBlockLocations

getServerDefaults

getServerDefaults

resolvePath

open

open

create

create

create

create

create

create

create

create

create

create

create

create

primitiveCreate

primitiveMkdir

primitiveMkdir

createNonRecursive

createNonRecursive

createNonRecursive

createNewFile

append

append

append

concat

getReplication

setReplication

rename

rename

delete

delete

deleteOnExit

cancelDeleteOnExit

processDeleteOnExit

exists