org.apache.cassandra.io.sstable

Class Descriptor

java.lang.Object

org.apache.cassandra.io.sstable.Descriptor

public class Descriptor
extends java.lang.Object

A SSTable is described by the keyspace and column family it contains data for, a generation (where higher generations contain more recent data) and an alphabetic version string. A descriptor can be marked as temporary, which influences generated filenames.

Field Summary

Fields

Modifier and Type	Field and Description
java.lang.String	cfname
java.io.File	directory canonicalized path to the directory where SSTable resides
SSTableFormat.Type	formatType
int	generation
java.lang.String	ksname
static java.lang.String	TMP_EXT
Version	version version has the following format: [a-z]+

Constructor Summary

Constructors

Constructor and Description
Descriptor(java.io.File directory, java.lang.String ksname, java.lang.String cfname, int generation) A descriptor that assumes CURRENT_VERSION.
Descriptor(java.io.File directory, java.lang.String ksname, java.lang.String cfname, int generation, SSTableFormat.Type formatType) Constructor for sstable writers only.
Descriptor(java.lang.String version, java.io.File directory, java.lang.String ksname, java.lang.String cfname, int generation, SSTableFormat.Type formatType)
Descriptor(Version version, java.io.File directory, java.lang.String ksname, java.lang.String cfname, int generation, SSTableFormat.Type formatType)

Method Summary

Modifier and Type	Method and Description
java.lang.String	baseFilename()
boolean	equals(java.lang.Object o)
java.lang.String	filenameFor(Component component)
static Descriptor	fromFilename(java.io.File file) Parse a sstable filename into a Descriptor.
static Descriptor	fromFilename(java.lang.String filename) Parse a sstable filename into a Descriptor.
static Pair<Descriptor,Component>	fromFilenameWithComponent(java.io.File file) Parse a sstable filename, extracting both the Descriptor and Component part.
SSTableFormat	getFormat()
IMetadataSerializer	getMetadataSerializer()
java.util.List<java.io.File>	getTemporaryFiles() Return any temporary files found in the directory
int	hashCode()
boolean	isCompatible()
static boolean	isValidFile(java.io.File file)
java.lang.String	relativeFilenameFor(Component component)
java.lang.String	tmpFilenameFor(Component component)
java.lang.String	tmpFilenameForStreaming(Component component)
java.lang.String	toString()
Descriptor	withFormatType(SSTableFormat.Type newType)
Descriptor	withGeneration(int newGeneration)

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Field Detail

TMP_EXT

public static java.lang.String TMP_EXT

directory

public final java.io.File directory

canonicalized path to the directory where SSTable resides

version

public final Version version

version has the following format: [a-z]+

ksname

public final java.lang.String ksname

cfname

public final java.lang.String cfname

generation

public final int generation

formatType

public final SSTableFormat.Type formatType

Constructor Detail

Descriptor

public Descriptor(java.io.File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  int generation)

A descriptor that assumes CURRENT_VERSION.

Descriptor

public Descriptor(java.io.File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  int generation,
                  SSTableFormat.Type formatType)

Constructor for sstable writers only.

Descriptor

public Descriptor(java.lang.String version,
                  java.io.File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  int generation,
                  SSTableFormat.Type formatType)

Descriptor

public Descriptor(Version version,
                  java.io.File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  int generation,
                  SSTableFormat.Type formatType)

Method Detail

withGeneration

public Descriptor withGeneration(int newGeneration)

withFormatType

public Descriptor withFormatType(SSTableFormat.Type newType)

tmpFilenameFor

public java.lang.String tmpFilenameFor(Component component)

tmpFilenameForStreaming

public java.lang.String tmpFilenameForStreaming(Component component)

Returns:

a unique temporary file name for given component during entire-sstable-streaming.

filenameFor

public java.lang.String filenameFor(Component component)

baseFilename

public java.lang.String baseFilename()

relativeFilenameFor

public java.lang.String relativeFilenameFor(Component component)

getFormat

public SSTableFormat getFormat()

getTemporaryFiles

public java.util.List<java.io.File> getTemporaryFiles()

Return any temporary files found in the directory

isValidFile

public static boolean isValidFile(java.io.File file)

fromFilename

public static Descriptor fromFilename(java.lang.String filename)

Parse a sstable filename into a Descriptor.

This is a shortcut for fromFilename(new File(filename)).

Parameters:

filename - the filename to a sstable component.

Returns:

the descriptor for the parsed file.

Throws:

java.lang.IllegalArgumentException - if the provided file does point to a valid sstable filename. This could mean either that the filename doesn't look like a sstable file, or that it is for an old and unsupported versions.

fromFilename

public static Descriptor fromFilename(java.io.File file)

Parse a sstable filename into a Descriptor.

SSTables files are all located within subdirectories of the form <keyspace>/<table>/. Normal sstables are are directly within that subdirectory structure while 2ndary index, backups and snapshot are each inside an additional subdirectory. The file themselves have the form: <version>-<gen>-<format>-<component>.

Note that this method will only sucessfully parse sstable files of supported versions.

Parameters:

file - the File object for the filename to parse.

Returns:

the descriptor for the parsed file.

Throws:

java.lang.IllegalArgumentException - if the provided file does point to a valid sstable filename. This could mean either that the filename doesn't look like a sstable file, or that it is for an old and unsupported versions.

fromFilenameWithComponent

public static Pair<Descriptor,Component> fromFilenameWithComponent(java.io.File file)

Parse a sstable filename, extracting both the Descriptor and Component part.

Parameters:

file - the File object for the filename to parse.

Returns:

a pair of the descriptor and component corresponding to the provided file.

Throws:

java.lang.IllegalArgumentException - if the provided file does point to a valid sstable filename. This could mean either that the filename doesn't look like a sstable file, or that it is for an old and unsupported versions.

getMetadataSerializer

public IMetadataSerializer getMetadataSerializer()

isCompatible

public boolean isCompatible()

Returns:

true if the current Cassandra version can read the given sstable version

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

equals

public boolean equals(java.lang.Object o)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object