Field Detail

• WAL_PROVIDER

  public static final String WAL_PROVIDER

  See Also:

  Constant Field Values

Constructor Detail

• WALFactory

  public WALFactory(org.apache.hadoop.conf.Configuration conf,
            List<WALActionsListener> listeners,
            String factoryId)
             throws IOException

  Parameters:

  conf - must not be null, will keep a reference to read params in later reader/writer instances.

  listeners - may be null. will be given to all created wals (and not meta-wals)

  factoryId - a unique identifier for this factory. used i.e. by filesystem implementations to make a directory

  Throws:

  IOException

Method Detail

• close

  public void close()
             throws IOException

  Shutdown all WALs and clean up any underlying storage. Use only when you will not need to replay and edits that have gone to any wals from this factory.

  Throws:

  IOException

• shutdown

  public void shutdown()
                throws IOException

  Tell the underlying WAL providers to shut down, but do not clean up underlying storage. If you are not ending cleanly and will need to replay edits from this factory's wals, use this method if you can as it will try to leave things as tidy as possible.

  Throws:

  IOException

• getWALs

  public List<WAL> getWALs()
                    throws IOException

  Throws:

  IOException

• getWAL

  public WAL getWAL(byte[] identifier,
           byte[] namespace)
             throws IOException

  Parameters:

  identifier - may not be null, contents will not be altered

  namespace - could be null, and will use default namespace if null

  Throws:

  IOException

• getMetaWAL

  public WAL getMetaWAL(byte[] identifier)
                 throws IOException

  Parameters:

  identifier - may not be null, contents will not be altered

  Throws:

  IOException

• createReader

  public WAL.Reader createReader(org.apache.hadoop.fs.FileSystem fs,
                        org.apache.hadoop.fs.Path path)
                          throws IOException

  Throws:

  IOException

• createReader

  public WAL.Reader createReader(org.apache.hadoop.fs.FileSystem fs,
                        org.apache.hadoop.fs.Path path,
                        CancelableProgressable reporter)
                          throws IOException

  Create a reader for the WAL. If you are reading from a file that's being written to and need to reopen it multiple times, use WAL.Reader.reset() instead of this method then just seek back to the last known good position.

  Returns:

  A WAL reader. Close when done with it.

  Throws:

  IOException

• createReader

  public WAL.Reader createReader(org.apache.hadoop.fs.FileSystem fs,
                        org.apache.hadoop.fs.Path path,
                        CancelableProgressable reporter,
                        boolean allowCustom)
                          throws IOException

  Throws:

  IOException

• createWALWriter

  public WALProvider.Writer createWALWriter(org.apache.hadoop.fs.FileSystem fs,
                                   org.apache.hadoop.fs.Path path)
                                     throws IOException

  Create a writer for the WAL. should be package-private. public only for tests and Compressor

  Returns:

  A WAL writer. Close when done with it.

  Throws:

  IOException

• createRecoveredEditsWriter

  public WALProvider.Writer createRecoveredEditsWriter(org.apache.hadoop.fs.FileSystem fs,
                                              org.apache.hadoop.fs.Path path)
                                                throws IOException

  should be package-private, visible for recovery testing.

  Returns:

  an overwritable writer for recovered edits. caller should close.

  Throws:

  IOException

• getInstance

  public static WALFactory getInstance(org.apache.hadoop.conf.Configuration configuration)

• createReader

  public static WAL.Reader createReader(org.apache.hadoop.fs.FileSystem fs,
                        org.apache.hadoop.fs.Path path,
                        org.apache.hadoop.conf.Configuration configuration)
                                 throws IOException

  Create a reader for the given path, accept custom reader classes from conf. If you already have a WALFactory, you should favor the instance method.

  Returns:

  a WAL Reader, caller must close.

  Throws:

  IOException

• createReaderIgnoreCustomClass

  public static WAL.Reader createReaderIgnoreCustomClass(org.apache.hadoop.fs.FileSystem fs,
                                         org.apache.hadoop.fs.Path path,
                                         org.apache.hadoop.conf.Configuration configuration)
                                                  throws IOException

  Create a reader for the given path, ignore custom reader classes from conf. If you already have a WALFactory, you should favor the instance method. only public pending move of Compressor

  Returns:

  a WAL Reader, caller must close.

  Throws:

  IOException

• createWALWriter

  public static WALProvider.Writer createWALWriter(org.apache.hadoop.fs.FileSystem fs,
                                   org.apache.hadoop.fs.Path path,
                                   org.apache.hadoop.conf.Configuration configuration)
                                            throws IOException

  If you already have a WALFactory, you should favor the instance method.

  Returns:

  a writer that won't overwrite files. Caller must close.

  Throws:

  IOException

• getWALProvider

  public final WALProvider getWALProvider()

• getMetaWALProvider

  public final WALProvider getMetaWALProvider()