org.apache.hadoop.fs.s3native
Class NativeS3FileSystem

java.lang.Object
  extended by org.apache.hadoop.conf.Configured
      extended by org.apache.hadoop.fs.FileSystem
          extended by org.apache.hadoop.fs.s3native.NativeS3FileSystem
All Implemented Interfaces:
Closeable, Configurable

@InterfaceAudience.Public
@InterfaceStability.Stable
public class NativeS3FileSystem
extends FileSystem

A FileSystem for reading and writing files stored on Amazon S3. Unlike S3FileSystem this implementation stores files on S3 in their native form so they can be read by other S3 tools. A note about directories. S3 of course has no "native" support for them. The idiom we choose then is: for any directory created by this class, we use an empty object "#{dirpath}_$folder$" as a marker. Further, to interoperate with other S3 tools, we also accept the following: - an object "#{dirpath}/' denoting a directory marker - if there exists any objects with the prefix "#{dirpath}/", then the directory is said to exist - if both a file with the name of a directory and a marker for that directory exists, then the *file masks the directory*, and the directory is never returned.

See Also:
S3FileSystem

Field Summary
static org.apache.commons.logging.Log LOG
           
 
Fields inherited from class org.apache.hadoop.fs.FileSystem
DEFAULT_FS, FS_DEFAULT_NAME_KEY, SHUTDOWN_HOOK_PRIORITY, statistics
 
Constructor Summary
NativeS3FileSystem()
           
NativeS3FileSystem(org.apache.hadoop.fs.s3native.NativeFileSystemStore store)
           
 
Method Summary
 FSDataOutputStream append(Path f, int bufferSize, Progressable progress)
          This optional operation is not yet supported.
 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.
 boolean delete(Path f, boolean recurse)
          Delete a file.
 long getDefaultBlockSize()
          Return the number of bytes that large input files should be optimally be split into to minimize i/o time.
 FileStatus getFileStatus(Path f)
          Return a file status object that represents the path.
 String getScheme()
          Return the protocol scheme for the FileSystem.
 URI getUri()
          Returns a URI whose scheme and authority identify this FileSystem.
 Path getWorkingDirectory()
          Get the current working directory for the given file system
 void initialize(URI uri, Configuration conf)
          Called after a new FileSystem instance is constructed.
 FileStatus[] listStatus(Path f)
           If f is a file, this method will make a single call to S3.
 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.
 void setWorkingDirectory(Path newDir)
          Set the working directory to the given directory.
 
Methods inherited from class org.apache.hadoop.fs.FileSystem
append, append, cancelDeleteOnExit, checkPath, clearStatistics, close, closeAll, closeAllForUGI, completeLocalOutput, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyToLocalFile, copyToLocalFile, copyToLocalFile, create, create, create, create, create, create, create, create, create, create, create, create, createNewFile, createNonRecursive, createNonRecursive, createNonRecursive, delete, deleteOnExit, exists, get, get, get, getAllStatistics, getBlockSize, getCanonicalUri, getContentSummary, getDefaultBlockSize, getDefaultPort, getDefaultReplication, getDefaultReplication, getDefaultUri, getFileBlockLocations, getFileBlockLocations, getFileChecksum, getFileSystemClass, getHomeDirectory, getInitialWorkingDirectory, getLength, getLocal, getName, getNamed, getReplication, getServerDefaults, getServerDefaults, getStatistics, getStatistics, getStatus, getStatus, getUsed, globStatus, globStatus, isDirectory, isFile, listCorruptFileBlocks, listFiles, listLocatedStatus, listLocatedStatus, listStatus, listStatus, listStatus, makeQualified, mkdirs, mkdirs, moveFromLocalFile, moveFromLocalFile, moveToLocalFile, newInstance, newInstance, newInstance, newInstanceLocal, open, primitiveCreate, primitiveMkdir, primitiveMkdir, printStatistics, processDeleteOnExit, rename, resolvePath, setDefaultUri, setDefaultUri, setOwner, setPermission, setReplication, setTimes, setVerifyChecksum, setWriteChecksum, startLocalOutput
 
Methods inherited from class org.apache.hadoop.conf.Configured
getConf, setConf
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Field Detail

LOG

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

NativeS3FileSystem

public NativeS3FileSystem()

NativeS3FileSystem

public NativeS3FileSystem(org.apache.hadoop.fs.s3native.NativeFileSystemStore store)
Method Detail

getScheme

public String getScheme()
Return the protocol scheme for the FileSystem.

Overrides:
getScheme in class FileSystem
Returns:
s3n

initialize

public void initialize(URI uri,
                       Configuration conf)
                throws IOException
Description copied from class: FileSystem
Called after a new FileSystem instance is constructed.

Overrides:
initialize in class FileSystem
Parameters:
uri - a uri whose authority section names the host, port, etc. for this FileSystem
conf - the configuration
Throws:
IOException

append

public FSDataOutputStream append(Path f,
                                 int bufferSize,
                                 Progressable progress)
                          throws IOException
This optional operation is not yet supported.

Specified by:
append in class FileSystem
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

create

public FSDataOutputStream create(Path f,
                                 FsPermission permission,
                                 boolean overwrite,
                                 int bufferSize,
                                 short replication,
                                 long blockSize,
                                 Progressable progress)
                          throws IOException
Description copied from class: FileSystem
Create an FSDataOutputStream at the indicated Path with write-progress reporting.

Specified by:
create in class FileSystem
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
See Also:
FileSystem.setPermission(Path, FsPermission)

delete

public boolean delete(Path f,
                      boolean recurse)
               throws IOException
Description copied from class: FileSystem
Delete a file.

Specified by:
delete in class FileSystem
Parameters:
f - the path to delete.
recurse - 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

getFileStatus

public FileStatus getFileStatus(Path f)
                         throws IOException
Description copied from class: FileSystem
Return a file status object that represents the path.

Specified by:
getFileStatus in class FileSystem
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

getUri

public URI getUri()
Description copied from class: FileSystem
Returns a URI whose scheme and authority identify this FileSystem.

Specified by:
getUri in class FileSystem

listStatus

public FileStatus[] listStatus(Path f)
                        throws IOException

If f is a file, this method will make a single call to S3. If f is a directory, this method will make a maximum of (n / 1000) + 2 calls to S3, where n is the total number of files and directories contained directly in f.

Specified by:
listStatus in class FileSystem
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

mkdirs

public boolean mkdirs(Path f,
                      FsPermission permission)
               throws IOException
Description copied from class: 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.

Specified by:
mkdirs in class FileSystem
Parameters:
f - path to create
permission - to apply to f
Throws:
IOException

open

public FSDataInputStream open(Path f,
                              int bufferSize)
                       throws IOException
Description copied from class: FileSystem
Opens an FSDataInputStream at the indicated Path.

Specified by:
open in class FileSystem
Parameters:
f - the file name to open
bufferSize - the size of the buffer to be used.
Throws:
IOException

rename

public boolean rename(Path src,
                      Path dst)
               throws IOException
Description copied from class: FileSystem
Renames Path src to Path dst. Can take place on local fs or remote DFS.

Specified by:
rename in class FileSystem
Parameters:
src - path to be renamed
dst - new path after rename
Returns:
true if rename is successful
Throws:
IOException - on failure

getDefaultBlockSize

public long getDefaultBlockSize()
Description copied from class: FileSystem
Return the number of bytes that large input files should be optimally be split into to minimize i/o time.

Overrides:
getDefaultBlockSize in class FileSystem

setWorkingDirectory

public void setWorkingDirectory(Path newDir)
Set the working directory to the given directory.

Specified by:
setWorkingDirectory in class FileSystem

getWorkingDirectory

public Path getWorkingDirectory()
Description copied from class: FileSystem
Get the current working directory for the given file system

Specified by:
getWorkingDirectory in class FileSystem
Returns:
the directory pathname


Copyright © 2012 Apache Software Foundation. All Rights Reserved.