com.pervasive.datarush.io

Class HadoopFileSystemProvider

java.lang.Object

com.pervasive.datarush.io.HadoopFileSystemProvider

All Implemented Interfaces:

FileSystemProvider

public class HadoopFileSystemProvider
extends Object
implements FileSystemProvider

Provides access to the Hadoop Distributed File System (HDFS). Paths are also valid HDFS paths. They are identified by the hdfs scheme and always specify an authority identifying the name node of the HDFS.

Field Summary

Fields

Modifier and Type	Field and Description
static HadoopFileSystemProvider	INSTANCE

Constructor Summary

Constructors

Constructor and Description
HadoopFileSystemProvider() Creates a new provider for HDFS.

Method Summary

Modifier and Type	Method and Description
FileConfiguration	getConfigurationTemplate() Returns a non-populated configuration object to server as a template that the user must fill-in.
Map<String,FileConfiguration>	getDefaultConfiguration() Gets default configuration for the schemes handled by the provider.
FileSystem	getFileSystem(FileClient client, FileConfiguration configuration, Path path) Gets the file system identified by the path.
Path	getFileSystemPath(Path path) Returns the filesystem root path associated with the given path.
Path	getPath(String path) Gets the path identified by the given string.
boolean	isPathSupported(String path) Indicates whether the given scheme is handled by the provider.

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final HadoopFileSystemProvider INSTANCE

Constructor Detail

HadoopFileSystemProvider

public HadoopFileSystemProvider()

Creates a new provider for HDFS.

This constructor is public as a matter of implementation only. Users should not construct a provider directly, but instead use the static methods contained in FileClient and Paths.

Method Detail

isPathSupported

public boolean isPathSupported(String path)

Description copied from interface: FileSystemProvider

Indicates whether the given scheme is handled by the provider.

Specified by:

isPathSupported in interface FileSystemProvider

Parameters:

path - an identifier for a path scheme

Returns:

true if this provider handles paths using the scheme, false otherwise.

getFileSystemPath

public Path getFileSystemPath(Path path)

Description copied from interface: FileSystemProvider

Returns the filesystem root path associated with the given path.

Specified by:

getFileSystemPath in interface FileSystemProvider

Parameters:

path - the path

Returns:

the root path

getFileSystem

public FileSystem getFileSystem(FileClient client,
                                FileConfiguration configuration,
                                Path path)

Description copied from interface: FileSystemProvider

Gets the file system identified by the path. The path identifies a file on the file system; the file's file system is returned. This is equivalent to calling getPath(path).getFileSystem(), but may be faster.

Specified by:

getFileSystem in interface FileSystemProvider

Parameters:

client - a file client. most implementations will ignore this parameter. "meta-filesystems" ( those than can span filesystems ) may need the file client.

configuration - the configuration for this filesystem

path - a path identifying a file on the file system

Returns:

the requested file system object

getPath

public Path getPath(String path)

Description copied from interface: FileSystemProvider

Gets the path identified by the given string. The resulting path represents a location in an abstract file system. Use the methods in FileClient to perform operations on the files and directories represented by paths.

Specified by:

getPath in interface FileSystemProvider

Parameters:

path - the path name to resolve into a path object

Returns:

the requested path object

getConfigurationTemplate

public FileConfiguration getConfigurationTemplate()

Description copied from interface: FileSystemProvider

Returns a non-populated configuration object to server as a template that the user must fill-in.

Specified by:

getConfigurationTemplate in interface FileSystemProvider

Returns:

a configuration template

getDefaultConfiguration

public Map<String,FileConfiguration> getDefaultConfiguration()

Description copied from interface: FileSystemProvider

Gets default configuration for the schemes handled by the provider. Default configuration is inherited from the execution environment.

A provider should return a map with entries only for schemes having default configuration; if no schemes do, an empty map should be returned.

Specified by:

getDefaultConfiguration in interface FileSystemProvider

Returns:

a mapping of schemes to default configuration