Package org.apache.bookkeeper.bookie

Class FileInfo

java.lang.Object

org.apache.bookkeeper.common.util.Watchable<LastAddConfirmedUpdateNotification>

org.apache.bookkeeper.bookie.FileInfo

All Implemented Interfaces:

Recyclable

Direct Known Subclasses:

FileInfoBackingCache.CachedFileInfo, ReadOnlyFileInfo

class FileInfo
extends Watchable<LastAddConfirmedUpdateNotification>

This is the file handle for a ledger's index file that maps entry ids to location. It is used by LedgerCache.

Ledger index file is made of a header and several fixed-length index pages, which records the offsets of data stored in entry loggers

<header><index pages>

Header is formatted as below:

<magic bytes><len of master key><master key>

• magic bytes: 4 bytes, 'BKLE', version: 4 bytes
• len of master key: indicates length of master key. -1 means no master key stored in header.
• master key: master key
• state: bit map to indicate the state, 32 bits.

Index page is a fixed-length page, which contains several entries which point to the offsets of data stored in entry loggers.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	FileInfo.FileInfoDeletedException

Field Summary

Fields

Modifier and Type	Field	Description
static final int	CURRENT_HEADER_VERSION
(package private) int	headerVersion
(package private) byte[]	masterKey
protected String	mode
(package private) static final int	NO_MASTER_KEY
static final int	SIGNATURE	The fingerprint of a ledger index file.
(package private) static final long	START_OF_DATA
(package private) static final int	STATE_FENCED_BIT
(package private) static final int	V0
(package private) static final int	V1

Constructor Summary

Constructors

Constructor	Description
FileInfo(File lf, byte[] masterKey, int fileInfoVersionToWrite)

Method Summary

Modifier and Type	Method	Description
(package private) void	cancelWaitForLastAddConfirmedUpdate(Watcher<LastAddConfirmedUpdateNotification> watcher)
(package private) void	checkOpen(boolean create)
void	close(boolean force)	Close a file info.
boolean	delete()
void	flushHeader()
io.netty.buffer.ByteBuf	getExplicitLac()
(package private) Long	getLastAddConfirmed()
File	getLf()
byte[]	getMasterKey()
long	getSizeSinceLastWrite()
boolean	isClosed()
boolean	isDeleted()
boolean	isFenced()
boolean	isSameFile(File f)
void	moveToNewLocation(File newFile, long size)	Copies current file contents upto specified size to the target file and deletes the current file.
int	read(ByteBuffer bb, long position, boolean bestEffort)
void	readHeader()
void	setExplicitLac(io.netty.buffer.ByteBuf lac)
boolean	setFenced()
(package private) long	setLastAddConfirmed(long lac)
long	size()
(package private) boolean	waitForLastAddConfirmedUpdate(long previousLAC, Watcher<LastAddConfirmedUpdateNotification> watcher)
long	write(ByteBuffer[] buffs, long position)

Methods inherited from class org.apache.bookkeeper.common.util.Watchable

addWatcher, deleteWatcher, deleteWatchers, notifyWatchers, recycle

Methods inherited from class java.lang.Object

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

Field Details

NO_MASTER_KEY

static final int NO_MASTER_KEY

See Also:

• Constant Field Values

STATE_FENCED_BIT

static final int STATE_FENCED_BIT

See Also:

• Constant Field Values

masterKey

byte[] masterKey

SIGNATURE

public static final int SIGNATURE

The fingerprint of a ledger index file.

V0

static final int V0

See Also:

• Constant Field Values

V1

static final int V1

See Also:

• Constant Field Values

CURRENT_HEADER_VERSION

public static final int CURRENT_HEADER_VERSION

See Also:

• Constant Field Values

START_OF_DATA

static final long START_OF_DATA

See Also:

• Constant Field Values

mode

protected String mode

headerVersion

int headerVersion

Constructor Details

FileInfo

public FileInfo(File lf,
 byte[] masterKey,
 int fileInfoVersionToWrite)
         throws IOException

Throws:

IOException

Method Details

getLastAddConfirmed

Long getLastAddConfirmed()

setLastAddConfirmed

long setLastAddConfirmed(long lac)

waitForLastAddConfirmedUpdate

boolean waitForLastAddConfirmedUpdate(long previousLAC,
 Watcher<LastAddConfirmedUpdateNotification> watcher)

cancelWaitForLastAddConfirmedUpdate

void cancelWaitForLastAddConfirmedUpdate(Watcher<LastAddConfirmedUpdateNotification> watcher)

isClosed

public boolean isClosed()

getLf

public File getLf()

getSizeSinceLastWrite

public long getSizeSinceLastWrite()

getExplicitLac

public io.netty.buffer.ByteBuf getExplicitLac()

setExplicitLac

public void setExplicitLac(io.netty.buffer.ByteBuf lac)

readHeader

public void readHeader()
                throws IOException

Throws:

IOException

isDeleted

public boolean isDeleted()

checkOpen

void checkOpen(boolean create)
        throws IOException

Throws:

IOException

isFenced

public boolean isFenced()
                 throws IOException

Throws:

IOException

setFenced

public boolean setFenced()
                  throws IOException

Returns:

true if set fence succeed, otherwise false when it already fenced or failed to set fenced.

Throws:

IOException

flushHeader

public void flushHeader()
                 throws IOException

Throws:

IOException

size

public long size()
          throws IOException

Throws:

IOException

read

public int read(ByteBuffer bb,
 long position,
 boolean bestEffort)
         throws IOException

Throws:

IOException

close

public void close(boolean force)
           throws IOException

Close a file info. Generally, force should be set to true. If set to false metadata will not be flushed and accessing metadata before restart and recovery will be unsafe (since reloading from the index file will cause metadata to be lost). Setting force=false helps avoid expensive file create during shutdown with many dirty ledgers, and is safe because ledger metadata will be recovered before being accessed again.

Parameters:

force - if set to true, the index is forced to create before closed, if set to false, the index is not forced to create.

Throws:

IOException

write

public long write(ByteBuffer[] buffs,
 long position)
           throws IOException

Throws:

IOException

moveToNewLocation

public void moveToNewLocation(File newFile,
 long size)
                       throws IOException

Copies current file contents upto specified size to the target file and deletes the current file. If size not known then pass size as Long.MAX_VALUE to copy complete file.

Throws:

IOException

getMasterKey

public byte[] getMasterKey()
                    throws IOException

Throws:

IOException

delete

public boolean delete()

isSameFile

public boolean isSameFile(File f)