org.apache.hadoop.fs
Class InMemoryFileSystem

java.lang.Object
  org.apache.hadoop.conf.Configured
      org.apache.hadoop.fs.FileSystem
          org.apache.hadoop.fs.FilterFileSystem
              org.apache.hadoop.fs.ChecksumFileSystem
                  org.apache.hadoop.fs.InMemoryFileSystem

All Implemented Interfaces:

Closeable, Configurable

Deprecated.

@Deprecated
public class InMemoryFileSystem
extends ChecksumFileSystem

An implementation of the in-memory filesystem. This implementation assumes that the file lengths are known ahead of time and the total lengths of all the files is below a certain number (like 100 MB, configurable). Use the API reserveSpaceWithCheckSum(Path f, int size) (see below for a description of the API for reserving space in the FS. The uri of this filesystem starts with ramfs:// .

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.hadoop.fs.FileSystem

FileSystem.Statistics

Field Summary

Fields inherited from class org.apache.hadoop.fs.FilterFileSystem

fs

Fields inherited from class org.apache.hadoop.fs.FileSystem

LOG, statistics

Constructor Summary

InMemoryFileSystem()
Deprecated.

InMemoryFileSystem(URI uri, Configuration conf)
Deprecated.

Method Summary

Path[]	getFiles(PathFilter filter) Deprecated.
long	getFSSize() Deprecated.
int	getNumFiles(PathFilter filter) Deprecated.
float	getPercentUsed() Deprecated.
boolean	reserveSpaceWithCheckSum(Path f, long size) Deprecated. Register a file with its size.

Methods inherited from class org.apache.hadoop.fs.ChecksumFileSystem

completeLocalOutput, copyFromLocalFile, copyToLocalFile, copyToLocalFile, create, delete, getApproxChkSumLength, getBytesPerSum, getChecksumFile, getChecksumFileLength, getChecksumLength, getRawFileSystem, isChecksumFile, listStatus, mkdirs, open, rename, reportChecksumFailure, setConf, setReplication, startLocalOutput

Methods inherited from class org.apache.hadoop.fs.FilterFileSystem

append, checkPath, close, create, delete, getConf, getDefaultBlockSize, getDefaultReplication, getFileBlockLocations, getFileBlockLocations, getFileStatus, getHomeDirectory, getName, getUri, getWorkingDirectory, initialize, makeQualified, mkdirs, setOwner, setPermission, setWorkingDirectory

Methods inherited from class org.apache.hadoop.fs.FileSystem

append, append, closeAll, copyFromLocalFile, copyFromLocalFile, copyFromLocalFile, copyToLocalFile, create, create, create, create, create, create, create, create, create, createNewFile, deleteOnExit, exists, get, get, getBlockSize, getContentSummary, getDefaultUri, getLength, getLocal, getNamed, getReplication, getStatistics, getUsed, globStatus, globStatus, isDirectory, isFile, listStatus, listStatus, listStatus, mkdirs, moveFromLocalFile, moveFromLocalFile, moveToLocalFile, open, parseArgs, printStatistics, processDeleteOnExit, setDefaultUri, setDefaultUri

Methods inherited from class java.lang.Object

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

Constructor Detail

InMemoryFileSystem

public InMemoryFileSystem()

Deprecated.

InMemoryFileSystem

public InMemoryFileSystem(URI uri,
                          Configuration conf)

Deprecated.

Method Detail

reserveSpaceWithCheckSum

public boolean reserveSpaceWithCheckSum(Path f,
                                        long size)

Deprecated.

Register a file with its size. This will also register a checksum for the file that the user is trying to create. This is required since none of the FileSystem APIs accept the size of the file as argument. But since it is required for us to apriori know the size of the file we are going to create, the user must call this method for each file he wants to create and reserve memory for that file. We either succeed in reserving memory for both the main file and the checksum file and return true, or return false.

getFiles

public Path[] getFiles(PathFilter filter)

Deprecated.

getNumFiles

public int getNumFiles(PathFilter filter)

Deprecated.

getFSSize

public long getFSSize()

Deprecated.

getPercentUsed

public float getPercentUsed()

Deprecated.