Package org.apache.cassandra.io.sstable

Class Descriptor

  • public class Descriptor
extends java.lang.Object
    A SSTable is described by the keyspace and column family it contains data for, an id (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 Detail

      • TMP_EXT

        public static java.lang.String TMP_EXT

      • directory

        public final 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

    • Constructor Detail

      • Descriptor

        public Descriptor​(File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  SSTableId id)
        A descriptor that assumes CURRENT_VERSION.

      • Descriptor

        public Descriptor​(File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  SSTableId id,
                  SSTableFormat<?,​?> format)
        Constructor for sstable writers only.

      • Descriptor

        public Descriptor​(java.lang.String version,
                  File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  SSTableId id,
                  SSTableFormat<?,​?> format)

      • Descriptor

        public Descriptor​(Version version,
                  File directory,
                  java.lang.String ksname,
                  java.lang.String cfname,
                  SSTableId id)

    • Method Detail

      • tmpFileForStreaming

        public File tmpFileForStreaming​(Component component)
        Returns:
        a unique temporary file name for given component during entire-sstable-streaming.

      • baseFile

        public File baseFile()

      • relativeFilenameFor

        public java.lang.String relativeFilenameFor​(Component component)

      • getTemporaryFiles

        public java.util.List<File> getTemporaryFiles()
        Return any temporary files found in the directory

      • getComponents

        public java.util.Set<Component> getComponents​(java.util.Set<Component> mandatory,
                                              java.util.Set<Component> optional)
        Returns the set of components consisting of the provided mandatory components and those optional components for which the corresponding file exists.

      • isValidFile

        public static boolean isValidFile​(File file)

      • fromFile

        public static Descriptor fromFile​(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.

      • componentFromFile

        public static Component componentFromFile​(File file)

      • fromFileWithComponent

        public static Pair<Descriptor,​Component> fromFileWithComponent​(File file)
        Parse a sstable filename, extracting both the Descriptor and Component part. The keyspace/table name will be extracted from the directory path.
        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.

      • fromFileWithComponent

        public static Pair<Descriptor,​Component> fromFileWithComponent​(File file,
                                                                     java.lang.String keyspace,
                                                                     java.lang.String table)
        Parse a sstable filename, extracting both the Descriptor and Component part.
        Parameters:
        file - the File object for the filename to parse.
        keyspace - The keyspace name of the file. If null, then the keyspace name will be extracted from the directory path.
        table - The table name of the file. If null, then the table name will be extracted from the directory path.
        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.

      • isCompatible

        public boolean isCompatible()
        Returns:
        true if the current Cassandra version can read the given sstable version

      • discoverComponents

        public java.util.Set<Component> discoverComponents()

      • 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