bitronix.tm.journal

Class TransactionLogHeader

java.lang.Object

bitronix.tm.journal.TransactionLogHeader

public class TransactionLogHeader
extends java.lang.Object

Used to control a log file's header.

The physical data is read when this object is created then cached. Calling setter methods sets the header field then moves the file pointer back to the previous location.

Author:

lorban

Field Summary

Fields

Modifier and Type	Field and Description
static byte	CLEAN_LOG_STATE State of the log file when it has been closed properly.
static int	CURRENT_POSITION_HEADER Position of the current log position in the header.
static int	FORMAT_ID_HEADER Position of the format ID in the header (see BitronixXid.FORMAT_ID).
static int	HEADER_LENGTH Total length of the header.
static int	STATE_HEADER Position of the log file state in the header.
static int	TIMESTAMP_HEADER Position of the timestamp in the header.
static byte	UNCLEAN_LOG_STATE State of the log file when it hasn't been closed properly or it is still open.

Constructor Summary

Constructors

Constructor and Description
TransactionLogHeader(java.nio.channels.FileChannel fc, long maxFileLength) TransactionLogHeader are used to control headers of the specified RandomAccessFile.

Method Summary

Modifier and Type	Method and Description
int	getFormatId() Get FORMAT_ID_HEADER.
long	getPosition() Get CURRENT_POSITION_HEADER.
byte	getState() Get STATE_HEADER.
long	getTimestamp() Get TIMESTAMP_HEADER.
void	goAhead(long distance) Advance CURRENT_POSITION_HEADER.
void	rewind() Rewind CURRENT_POSITION_HEADER back to the beginning of the file.
void	setFormatId(int formatId) Set FORMAT_ID_HEADER.
void	setPosition(long position) Set CURRENT_POSITION_HEADER.
void	setState(byte state) Set STATE_HEADER.
void	setTimestamp(long timestamp) Set TIMESTAMP_HEADER.
java.lang.String	toString() Create human-readable String representation.

Methods inherited from class java.lang.Object

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

Field Detail

FORMAT_ID_HEADER

public static final int FORMAT_ID_HEADER

Position of the format ID in the header (see BitronixXid.FORMAT_ID).

See Also:

Constant Field Values

TIMESTAMP_HEADER

public static final int TIMESTAMP_HEADER

Position of the timestamp in the header.

See Also:

Constant Field Values

STATE_HEADER

public static final int STATE_HEADER

Position of the log file state in the header.

See Also:

Constant Field Values

CURRENT_POSITION_HEADER

public static final int CURRENT_POSITION_HEADER

Position of the current log position in the header.

See Also:

Constant Field Values

HEADER_LENGTH

public static final int HEADER_LENGTH

Total length of the header.

See Also:

Constant Field Values

CLEAN_LOG_STATE

public static final byte CLEAN_LOG_STATE

State of the log file when it has been closed properly.

See Also:

Constant Field Values

UNCLEAN_LOG_STATE

public static final byte UNCLEAN_LOG_STATE

State of the log file when it hasn't been closed properly or it is still open.

See Also:

Constant Field Values

Constructor Detail

TransactionLogHeader

public TransactionLogHeader(java.nio.channels.FileChannel fc,
                            long maxFileLength)
                     throws java.io.IOException

TransactionLogHeader are used to control headers of the specified RandomAccessFile. All calls to setters are synchronized on the passed-in RandomAccessFile.

Parameters:

fc - the file channel to read from.

maxFileLength - the max file length.

Throws:

java.io.IOException - if an I/O error occurs.

Method Detail

getFormatId

public int getFormatId()

Get FORMAT_ID_HEADER.

Returns:

the FORMAT_ID_HEADER value.

See Also:

FORMAT_ID_HEADER

getTimestamp

public long getTimestamp()

Get TIMESTAMP_HEADER.

Returns:

the TIMESTAMP_HEADER value.

See Also:

TIMESTAMP_HEADER

getState

public byte getState()

Get STATE_HEADER.

Returns:

the STATE_HEADER value.

See Also:

STATE_HEADER

getPosition

public long getPosition()

Get CURRENT_POSITION_HEADER.

Returns:

the CURRENT_POSITION_HEADER value.

See Also:

CURRENT_POSITION_HEADER

setFormatId

public void setFormatId(int formatId)
                 throws java.io.IOException

Set FORMAT_ID_HEADER.

Parameters:

formatId - the FORMAT_ID_HEADER value.

Throws:

java.io.IOException - if an I/O error occurs.

See Also:

FORMAT_ID_HEADER

setTimestamp

public void setTimestamp(long timestamp)
                  throws java.io.IOException

Set TIMESTAMP_HEADER.

Parameters:

timestamp - the TIMESTAMP_HEADER value.

Throws:

java.io.IOException - if an I/O error occurs.

See Also:

TIMESTAMP_HEADER

setState

public void setState(byte state)
              throws java.io.IOException

Set STATE_HEADER.

Parameters:

state - the STATE_HEADER value.

Throws:

java.io.IOException - if an I/O error occurs.

See Also:

STATE_HEADER

setPosition

public void setPosition(long position)
                 throws java.io.IOException

Set CURRENT_POSITION_HEADER.

Parameters:

position - the CURRENT_POSITION_HEADER value.

Throws:

java.io.IOException - if an I/O error occurs.

See Also:

CURRENT_POSITION_HEADER

goAhead

public void goAhead(long distance)
             throws java.io.IOException

Advance CURRENT_POSITION_HEADER.

Parameters:

distance - the value to add to the current position.

Throws:

java.io.IOException - if an I/O error occurs.

See Also:

setPosition(long)

rewind

public void rewind()
            throws java.io.IOException

Rewind CURRENT_POSITION_HEADER back to the beginning of the file.

Throws:

java.io.IOException - if an I/O error occurs.

See Also:

setPosition(long)

toString

public java.lang.String toString()

Create human-readable String representation.

Overrides:

toString in class java.lang.Object

Returns:

a human-readable String representing this object's state.