Package alluxio.util

Class UnderFileSystemUtils

java.lang.Object

alluxio.util.UnderFileSystemUtils

@ThreadSafe
public final class UnderFileSystemUtils
extends java.lang.Object

Utility functions for working with UnderFileSystem.

Method Summary

Modifier and Type	Method	Description
static java.lang.String	approximateContentHash(long length, long modTime)	Returns an approximate content hash, using the length and modification time.
static void	deleteDirIfExists(UnderFileSystem ufs, java.lang.String path)	Deletes the directory at the given path if it exists.
static void	deleteFileIfExists(UnderFileSystem ufs, java.lang.String path)	Deletes the specified path from the specified under file system if it is a file and exists.
static java.lang.String	getBucketName(AlluxioURI uri)
static boolean	isCephFS(UnderFileSystem ufs)
static boolean	isGcs(UnderFileSystem ufs)
static boolean	isHdfs(UnderFileSystem ufs)
static boolean	isLocal(UnderFileSystem ufs)
static boolean	isOss(UnderFileSystem ufs)
static boolean	isS3(UnderFileSystem ufs)
static boolean	isSwift(UnderFileSystem ufs)
static boolean	isWeb(UnderFileSystem ufs)
static void	mkdirIfNotExists(UnderFileSystem ufs, java.lang.String path)	Attempts to create the directory if it does not already exist.
static void	touch(UnderFileSystem ufs, java.lang.String path)	Creates an empty file.

Methods inherited from class java.lang.Object

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

Method Detail

deleteDirIfExists

public static void deleteDirIfExists(UnderFileSystem ufs,
                                     java.lang.String path)
                              throws java.io.IOException

Deletes the directory at the given path if it exists.

Parameters:

ufs - instance of UnderFileSystem

path - path to the directory

Throws:

java.io.IOException

mkdirIfNotExists

public static void mkdirIfNotExists(UnderFileSystem ufs,
                                    java.lang.String path)
                             throws java.io.IOException

Attempts to create the directory if it does not already exist.

Parameters:

ufs - instance of UnderFileSystem

path - path to the directory

Throws:

java.io.IOException

touch

public static void touch(UnderFileSystem ufs,
                         java.lang.String path)
                  throws java.io.IOException

Creates an empty file.

Parameters:

ufs - instance of UnderFileSystem

path - path to the file

Throws:

java.io.IOException

deleteFileIfExists

public static void deleteFileIfExists(UnderFileSystem ufs,
                                      java.lang.String path)

Deletes the specified path from the specified under file system if it is a file and exists.

Parameters:

ufs - instance of UnderFileSystem

path - the path to delete

isGcs

public static boolean isGcs(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is a Google cloud store implementation

isLocal

public static boolean isLocal(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is a local file system implementation

isHdfs

public static boolean isHdfs(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is a Hadoop distributed file system implementation

isOss

public static boolean isOss(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is an Object storage service implementation

isS3

public static boolean isS3(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is an S3 implementation

isSwift

public static boolean isSwift(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is a Swift storage implementation

isWeb

public static boolean isWeb(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is a Http implementation

isCephFS

public static boolean isCephFS(UnderFileSystem ufs)

Parameters:

ufs - the UnderFileSystem implementation to check

Returns:

true if the implementation is a Cephfs storage implementation

getBucketName

public static java.lang.String getBucketName(AlluxioURI uri)

Parameters:

uri - the UFS path

Returns:

the bucket or container name of the object storage

approximateContentHash

public static java.lang.String approximateContentHash(long length,
                                                      long modTime)

Returns an approximate content hash, using the length and modification time.

Parameters:

length - the content length

modTime - the content last modification time

Returns:

the content hash