org.apache.hadoop.hdfs.web

类 WebHdfsFileSystem

java.lang.Object

org.apache.hadoop.conf.Configured

org.apache.hadoop.fs.FileSystem

org.apache.hadoop.hdfs.web.WebHdfsFileSystem

所有已实现的接口:

Closeable, AutoCloseable, Configurable, DelegationTokenRenewer.Renewable

public class WebHdfsFileSystem
extends FileSystem
implements DelegationTokenRenewer.Renewable

A FileSystem for HDFS over the web.

嵌套类概要

嵌套类

限定符和类型	类和说明
static class	WebHdfsFileSystem.DtRenewer Delegation token renewer.

从类继承的嵌套类/接口 org.apache.hadoop.fs.FileSystem

FileSystem.Statistics

字段概要

字段

限定符和类型	字段和说明
static AbstractDelegationTokenSelector<DelegationTokenIdentifier>	DT_SELECTOR Token selector
static org.apache.commons.logging.Log	LOG
static String	PATH_PREFIX Http URI: http://namenode:port/{PATH_PREFIX}/path/to/file
static String	SCHEME File System URI: {SCHEME}://namenode:port/path/to/file
static Text	TOKEN_KIND Delegation token kind
static int	VERSION WebHdfs version.

从类继承的字段 org.apache.hadoop.fs.FileSystem

FS_DEFAULT_NAME_KEY, statistics

构造器概要

构造器

构造器和说明
WebHdfsFileSystem()

方法概要

方法

限定符和类型	方法和说明
FSDataOutputStream	append(Path f, int bufferSize, Progressable progress) Append to an existing file (optional operation).
void	concat(Path trg, Path[] srcs) Concat existing files together.
FSDataOutputStream	create(Path f, FsPermission permission, boolean overwrite, int bufferSize, short replication, long blockSize, Progressable progress) Opens an FSDataOutputStream at the indicated Path with write-progress reporting.
boolean	delete(Path f)
boolean	delete(Path f, boolean recursive) Delete a file.
ContentSummary	getContentSummary(Path p) Return the ContentSummary of a given Path.
long	getDefaultBlockSize() 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() Get the default replication.
Token<DelegationTokenIdentifier>	getDelegationToken(String renewer) Get a new delegation token for this file system.
BlockLocation[]	getFileBlockLocations(FileStatus status, long offset, long length) Return an array containing hostnames, offset and size of portions of the given file.
MD5MD5CRC32FileChecksum	getFileChecksum(Path p) Get the checksum of a file.
FileStatus	getFileStatus(Path f) Return a file status object that represents the path.
Path	getHomeDirectory() Return the current user's home directory in this filesystem.
static String	getHomeDirectoryString(UserGroupInformation ugi)
Token<?>	getRenewToken()
URI	getUri() Returns a URI whose scheme and authority identify this FileSystem.
Path	getWorkingDirectory() Get the current working directory for the given file system
protected void	initDelegationToken()
void	initialize(URI uri, Configuration conf) Called after a new FileSystem instance is constructed.
static boolean	isEnabled(Configuration conf, org.apache.commons.logging.Log log) Is WebHDFS enabled in conf?
FileStatus[]	listStatus(Path f) List the statuses of the files/directories in the given path if the path is a directory.
boolean	mkdirs(Path f, FsPermission permission) Make the given file and all non-existent parents into directories.
FSDataInputStream	open(Path f, int buffersize) Opens an FSDataInputStream at the indicated Path.
boolean	rename(Path src, Path dst) Renames Path src to Path dst.
<T extends TokenIdentifier> void	setDelegationToken(Token<T> token) Set delegation token.
void	setOwner(Path p, String owner, String group) Set owner of a path (i.e. a file or a directory).
void	setPermission(Path p, FsPermission permission) Set permission of a path.
boolean	setReplication(Path p, short replication) Set replication for an existing file.
void	setTimes(Path p, long mtime, long atime) Set access time of a file
void	setWorkingDirectory(Path dir) Set the current working directory for the given file system.

从类继承的方法 org.apache.hadoop.fs.FileSystem

addFileSystemForTesting, append, append, checkPath, clearStatistics, close, closeAll, closeAllForUGI, completeLocalOutput, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyToLocalFile, copyToLocalFile, create, create, create, create, create, create, create, create, create, create, createNewFile, createNonRecursive, createNonRecursive, deleteOnExit, exists, get, get, get, getAllStatistics, getBlockSize, getCacheSize, getCanonicalServiceName, getCanonicalUri, getDefaultBlockSize, getDefaultReplication, getDefaultUri, getLength, getLocal, getName, getNamed, getReplication, getStatistics, getStatistics, getUsed, globStatus, globStatus, isDirectory, isFile, listStatus, listStatus, listStatus, makeQualified, mkdirs, mkdirs, moveFromLocalFile, moveFromLocalFile, moveToLocalFile, open, printStatistics, processDeleteOnExit, setDefaultUri, setDefaultUri, setVerifyChecksum, startLocalOutput

从类继承的方法 org.apache.hadoop.conf.Configured

getConf, setConf

从类继承的方法 java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

字段详细资料

LOG

public static final org.apache.commons.logging.Log LOG

SCHEME

public static final String SCHEME

File System URI: {SCHEME}://namenode:port/path/to/file

另请参阅:

常量字段值

VERSION

public static final int VERSION

WebHdfs version.

另请参阅:

常量字段值

PATH_PREFIX

public static final String PATH_PREFIX

Http URI: http://namenode:port/{PATH_PREFIX}/path/to/file

另请参阅:

常量字段值

TOKEN_KIND

public static final Text TOKEN_KIND

Delegation token kind

DT_SELECTOR

public static final AbstractDelegationTokenSelector<DelegationTokenIdentifier> DT_SELECTOR

Token selector

构造器详细资料

WebHdfsFileSystem

public WebHdfsFileSystem()

方法详细资料

isEnabled

public static boolean isEnabled(Configuration conf,
                org.apache.commons.logging.Log log)

Is WebHDFS enabled in conf?

initialize

public void initialize(URI uri,
              Configuration conf)
                throws IOException

从类复制的说明: FileSystem

Called after a new FileSystem instance is constructed.

覆盖:

initialize 在类中 FileSystem

参数:

uri - a uri whose authority section names the host, port, etc. for this FileSystem

conf - the configuration

抛出:

IOException

initDelegationToken

protected void initDelegationToken()
                            throws IOException

抛出:

IOException

getDefaultPort

protected int getDefaultPort()

从类复制的说明: FileSystem

Get the default port for this file system.

覆盖:

getDefaultPort 在类中 FileSystem

返回:

the default port or 0 if there isn't one

getUri

public URI getUri()

从类复制的说明: FileSystem

Returns a URI whose scheme and authority identify this FileSystem.

指定者:

getUri 在类中 FileSystem

getHomeDirectoryString

public static String getHomeDirectoryString(UserGroupInformation ugi)

返回:

the home directory.

getHomeDirectory

public Path getHomeDirectory()

从类复制的说明: FileSystem

Return the current user's home directory in this filesystem. The default implementation returns "/user/$USER/".

覆盖:

getHomeDirectory 在类中 FileSystem

getWorkingDirectory

public Path getWorkingDirectory()

从类复制的说明: FileSystem

Get the current working directory for the given file system

指定者:

getWorkingDirectory 在类中 FileSystem

返回:

the directory pathname

setWorkingDirectory

public void setWorkingDirectory(Path dir)

从类复制的说明: FileSystem

Set the current working directory for the given file system. All relative paths will be resolved relative to it.

指定者:

setWorkingDirectory 在类中 FileSystem

getFileStatus

public FileStatus getFileStatus(Path f)
                         throws IOException

从类复制的说明: FileSystem

Return a file status object that represents the path.

指定者:

getFileStatus 在类中 FileSystem

参数:

f - The path we want information from

返回:

a FileStatus object

抛出:

FileNotFoundException - when the path does not exist; IOException see specific implementation

IOException

mkdirs

public boolean mkdirs(Path f,
             FsPermission permission)
               throws IOException

从类复制的说明: FileSystem

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.

指定者:

mkdirs 在类中 FileSystem

抛出:

IOException

rename

public boolean rename(Path src,
             Path dst)
               throws IOException

从类复制的说明: FileSystem

Renames Path src to Path dst. Can take place on local fs or remote DFS.

指定者:

rename 在类中 FileSystem

抛出:

IOException

setOwner

public void setOwner(Path p,
            String owner,
            String group)
              throws IOException

从类复制的说明: FileSystem

Set owner of a path (i.e. a file or a directory). The parameters username and groupname cannot both be null.

覆盖:

setOwner 在类中 FileSystem

参数:

p - The path

owner - If it is null, the original username remains unchanged.

group - If it is null, the original groupname remains unchanged.

抛出:

IOException

setPermission

public void setPermission(Path p,
                 FsPermission permission)
                   throws IOException

从类复制的说明: FileSystem

Set permission of a path.

覆盖:

setPermission 在类中 FileSystem

抛出:

IOException

setReplication

public boolean setReplication(Path p,
                     short replication)
                       throws IOException

从类复制的说明: FileSystem

Set replication for an existing file.

覆盖:

setReplication 在类中 FileSystem

参数:

p - file name

replication - new replication

返回:

true if successful; false if file does not exist or is a directory

抛出:

IOException

setTimes

public void setTimes(Path p,
            long mtime,
            long atime)
              throws IOException

从类复制的说明: FileSystem

Set access time of a file

覆盖:

setTimes 在类中 FileSystem

参数:

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.

抛出:

IOException

getDefaultBlockSize

public long getDefaultBlockSize()

从类复制的说明: FileSystem

Return the number of bytes that large input files should be optimally be split into to minimize i/o time.

覆盖:

getDefaultBlockSize 在类中 FileSystem

getDefaultReplication

public short getDefaultReplication()

从类复制的说明: FileSystem

Get the default replication.

覆盖:

getDefaultReplication 在类中 FileSystem

concat

public void concat(Path trg,
          Path[] srcs)
            throws IOException

从类复制的说明: FileSystem

Concat existing files together.

覆盖:

concat 在类中 FileSystem

参数:

trg - the path to the target destination.

抛出:

IOException

create

public FSDataOutputStream create(Path f,
                        FsPermission permission,
                        boolean overwrite,
                        int bufferSize,
                        short replication,
                        long blockSize,
                        Progressable progress)
                          throws IOException

从类复制的说明: FileSystem

Opens an FSDataOutputStream at the indicated Path with write-progress reporting.

指定者:

create 在类中 FileSystem

参数:

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.

抛出:

IOException

另请参阅:

FileSystem.setPermission(Path, FsPermission)

append

public FSDataOutputStream append(Path f,
                        int bufferSize,
                        Progressable progress)
                          throws IOException

从类复制的说明: FileSystem

Append to an existing file (optional operation).

指定者:

append 在类中 FileSystem

参数:

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.

抛出:

IOException

delete

public boolean delete(Path f)
               throws IOException

指定者:

delete 在类中 FileSystem

抛出:

IOException

delete

public boolean delete(Path f,
             boolean recursive)
               throws IOException

从类复制的说明: FileSystem

Delete a file.

指定者:

delete 在类中 FileSystem

参数:

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.

返回:

true if delete is successful else false.

抛出:

IOException

open

public FSDataInputStream open(Path f,
                     int buffersize)
                       throws IOException

从类复制的说明: FileSystem

Opens an FSDataInputStream at the indicated Path.

指定者:

open 在类中 FileSystem

参数:

f - the file name to open

buffersize - the size of the buffer to be used.

抛出:

IOException

listStatus

public FileStatus[] listStatus(Path f)
                        throws IOException

从类复制的说明: FileSystem

List the statuses of the files/directories in the given path if the path is a directory.

指定者:

listStatus 在类中 FileSystem

参数:

f - given path

返回:

the statuses of the files/directories in the given patch returns null, if Path f does not exist in the FileSystem

抛出:

IOException

getDelegationToken

public Token<DelegationTokenIdentifier> getDelegationToken(String renewer)
                                                    throws IOException

从类复制的说明: FileSystem

Get a new delegation token for this file system.

覆盖:

getDelegationToken 在类中 FileSystem

参数:

renewer - the account name that is allowed to renew the token.

返回:

a new delegation token

抛出:

IOException

getRenewToken

public Token<?> getRenewToken()

指定者:

getRenewToken 在接口中 DelegationTokenRenewer.Renewable

返回:

the renew token.

setDelegationToken

public <T extends TokenIdentifier> void setDelegationToken(Token<T> token)

从接口复制的说明: DelegationTokenRenewer.Renewable

Set delegation token.

指定者:

setDelegationToken 在接口中 DelegationTokenRenewer.Renewable

getFileBlockLocations

public BlockLocation[] getFileBlockLocations(FileStatus status,
                                    long offset,
                                    long length)
                                      throws IOException

从类复制的说明: FileSystem

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'.

覆盖:

getFileBlockLocations 在类中 FileSystem

抛出:

IOException

getContentSummary

public ContentSummary getContentSummary(Path p)
                                 throws IOException

从类复制的说明: FileSystem

Return the ContentSummary of a given Path.

覆盖:

getContentSummary 在类中 FileSystem

抛出:

IOException

getFileChecksum

public MD5MD5CRC32FileChecksum getFileChecksum(Path p)
                                        throws IOException

从类复制的说明: FileSystem

Get the checksum of a file.

覆盖:

getFileChecksum 在类中 FileSystem

参数:

p - The file path

返回:

The file checksum. The default return value is null, which indicates that no checksum algorithm is implemented in the corresponding FileSystem.

抛出:

IOException