org.apache.hadoop.hbase.regionserver.wal

Class SequenceFileLogReader

java.lang.Object

org.apache.hadoop.hbase.regionserver.wal.ReaderBase

org.apache.hadoop.hbase.regionserver.wal.SequenceFileLogReader

All Implemented Interfaces:

Closeable, AutoCloseable, DefaultWALProvider.Reader, WAL.Reader

@InterfaceAudience.LimitedPrivate(value={"Coprocesssor","Phoenix","Configuration"})
public class SequenceFileLogReader
extends ReaderBase

Field Summary

Fields

Modifier and Type	Field and Description
protected org.apache.hadoop.io.SequenceFile.Reader	reader

Fields inherited from class org.apache.hadoop.hbase.regionserver.wal.ReaderBase

compressionContext, conf, edit, emptyCompressionContext, fileLength, fs, path

Constructor Summary

Constructors

Constructor and Description
SequenceFileLogReader()

Method Summary

Methods

Modifier and Type	Method and Description
protected IOException	addFileInfoToException(IOException ioe)
void	close()
long	getPosition()
protected boolean	hasCompression()
protected boolean	hasTagCompression()
protected void	initAfterCompression() Initializes the compression after the shared stuff has been initialized.
protected void	initAfterCompression(String cellCodecClsName) Initializes the compression after the shared stuff has been initialized.
protected String	initReader(org.apache.hadoop.fs.FSDataInputStream stream) Initializes the log reader with a particular stream (may be null).
protected boolean	readNext(WAL.Entry e) fill in the passed entry with teh next key/value.
void	reset()
protected void	seekOnFs(long pos) Performs a filesystem-level seek to a certain position in an underlying file.

Methods inherited from class org.apache.hadoop.hbase.regionserver.wal.ReaderBase

init, next, next, seek

Methods inherited from class java.lang.Object

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

Field Detail

reader

protected org.apache.hadoop.io.SequenceFile.Reader reader

Constructor Detail

SequenceFileLogReader

public SequenceFileLogReader()

Method Detail

close

public void close()
           throws IOException

Throws:

IOException

getPosition

public long getPosition()
                 throws IOException

Throws:

IOException

reset

public void reset()
           throws IOException

Throws:

IOException

initReader

protected String initReader(org.apache.hadoop.fs.FSDataInputStream stream)
                     throws IOException

Description copied from class: ReaderBase

Initializes the log reader with a particular stream (may be null). Reader assumes ownership of the stream if not null and may use it. Called once.

Specified by:

initReader in class ReaderBase

Returns:

the class name of cell Codec, null if such information is not available

Throws:

IOException

initAfterCompression

protected void initAfterCompression(String cellCodecClsName)
                             throws IOException

Description copied from class: ReaderBase

Initializes the compression after the shared stuff has been initialized. Called once.

Specified by:

initAfterCompression in class ReaderBase

Parameters:

cellCodecClsName - class name of cell Codec

Throws:

IOException

initAfterCompression

protected void initAfterCompression()
                             throws IOException

Description copied from class: ReaderBase

Initializes the compression after the shared stuff has been initialized. Called once.

Specified by:

initAfterCompression in class ReaderBase

Throws:

IOException

hasCompression

protected boolean hasCompression()

Specified by:

hasCompression in class ReaderBase

Returns:

Whether compression is enabled for this log.

hasTagCompression

protected boolean hasTagCompression()

Specified by:

hasTagCompression in class ReaderBase

Returns:

Whether tag compression is enabled for this log.

readNext

protected boolean readNext(WAL.Entry e)
                    throws IOException

fill in the passed entry with teh next key/value. Note that because this format deals with our legacy storage, the provided Entery MUST use an HLogKey for the key.

Specified by:

readNext in class ReaderBase

Parameters:

e - The entry to read into.

Returns:

boolean indicating if the contents of Entry have been filled in.

Throws:

IOException

seekOnFs

protected void seekOnFs(long pos)
                 throws IOException

Description copied from class: ReaderBase

Performs a filesystem-level seek to a certain position in an underlying file.

Specified by:

seekOnFs in class ReaderBase

Throws:

IOException

addFileInfoToException

protected IOException addFileInfoToException(IOException ioe)
                                      throws IOException

Throws:

IOException