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

java.lang.String	cfname
static java.lang.String	CURRENT_VERSION
java.io.File	directory
int	generation
boolean	hasCompressionRatio
boolean	hasEncodedKeys
boolean	hasIntRowSize
boolean	hasPartitioner
boolean	hasStringsInBloomFilter
boolean	isLatestVersion
java.lang.String	ksname
static java.lang.String	LEGACY_VERSION
boolean	metadataIncludesReplayPosition
boolean	temporary
boolean	tracksMaxTimestamp
boolean	usesOldBloomFilter
java.lang.String	version version has the following format: [a-z]+

Constructor Summary

Descriptor(java.io.File directory, java.lang.String ksname, java.lang.String cfname, int generation, boolean temp)
A descriptor that assumes CURRENT_VERSION.

Descriptor(java.lang.String version, java.io.File directory, java.lang.String ksname, java.lang.String cfname, int generation, boolean temp)

Method Summary

Descriptor	asTemporary(boolean temporary)
boolean	containsTimestamp() Versions [h..hc] contained a timestamp value that was computed incorrectly, ignoring row tombstones.
boolean	equals(java.lang.Object o)
static java.lang.String	extractKeyspaceName(java.io.File directory) Extracts the keyspace name out of the directory name.
java.lang.String	filenameFor(Component component)
java.lang.String	filenameFor(java.lang.String suffix)
static Pair<Descriptor,java.lang.String>	fromFilename(java.io.File directory, java.lang.String name) Filename of the form "/-[tmp-][-]-"
static Descriptor	fromFilename(java.lang.String filename)
int	hashCode()
boolean	isCompatible()
boolean	isStreamCompatible()
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

LEGACY_VERSION

public static final java.lang.String LEGACY_VERSION

See Also:

Constant Field Values

CURRENT_VERSION

public static final java.lang.String CURRENT_VERSION

See Also:

Constant Field Values

directory

public final java.io.File directory

version

public final java.lang.String 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

temporary

public final boolean temporary

hasStringsInBloomFilter

public final boolean hasStringsInBloomFilter

hasIntRowSize

public final boolean hasIntRowSize

hasEncodedKeys

public final boolean hasEncodedKeys

isLatestVersion

public final boolean isLatestVersion

usesOldBloomFilter

public final boolean usesOldBloomFilter

metadataIncludesReplayPosition

public final boolean metadataIncludesReplayPosition

tracksMaxTimestamp

public final boolean tracksMaxTimestamp

hasCompressionRatio

public final boolean hasCompressionRatio

hasPartitioner

public final boolean hasPartitioner

Constructor Detail

Descriptor

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

A descriptor that assumes CURRENT_VERSION.

Descriptor

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

Method Detail

filenameFor

public java.lang.String filenameFor(Component component)

filenameFor

public java.lang.String filenameFor(java.lang.String suffix)

Parameters:

suffix - A component suffix, such as 'Data.db'/'Index.db'/etc

Returns:

A filename for this descriptor with the given suffix.

fromFilename

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

Parameters:

filename - The SSTable filename

Returns:

Descriptor of the SSTable initialized from filename

See Also:

fromFilename(File directory, String name)

fromFilename

public static Pair<Descriptor,java.lang.String> fromFilename(java.io.File directory,
                                                             java.lang.String name)

Filename of the form "/-[tmp-][-]-"

Parameters:

directory - The directory of the SSTable files

name - The name of the SSTable file

Returns:

A Descriptor for the SSTable, and the Component remainder.

extractKeyspaceName

public static java.lang.String extractKeyspaceName(java.io.File directory)

Extracts the keyspace name out of the directory name. Snapshot directories have a slightly different path structure and need to be treated differently. Regular path: "/-[tmp-][-]-" Snapshot path: "/snapshots//-[tmp-][-]-"

Parameters:

directory - a directory containing SSTables

Returns:

the keyspace name

asTemporary

public Descriptor asTemporary(boolean temporary)

Parameters:

temporary - temporary flag

Returns:

A clone of this descriptor with the given 'temporary' status.

isCompatible

public boolean isCompatible()

Returns:

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

isStreamCompatible

public boolean isStreamCompatible()

Returns:

true if the current Cassandra version can stream the given sstable version from another node. This is stricter than opening it locally [isCompatible] because streaming needs to rebuild all the non-data components, and it only knows how to write the latest version.

containsTimestamp

public boolean containsTimestamp()

Versions [h..hc] contained a timestamp value that was computed incorrectly, ignoring row tombstones. containsTimestamp returns true if there is a timestamp value in the metadata file; to know if it actually contains a *correct* timestamp, see tracksMaxTimestamp.

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