com.sleepycat.je.log
Class FileHeader

java.lang.Object
  com.sleepycat.je.log.FileHeader

All Implemented Interfaces:

LoggableObject, LogReadable, LogWritable

public class FileHeader
extends Object
implements LoggableObject, LogReadable

A FileHeader embodies the header information at the beginning of each log file.

Constructor Summary

FileHeader()
For logging only.

FileHeader(long fileNum, long lastEntryInPrevFileOffset)

Method Summary

boolean	countAsObsoleteWhenLogged() Returns true if this item should be counted as obsoleted when logged.
void	dumpLog(StringBuffer sb, boolean verbose) Write the object into the string buffer for log dumping.
(package private) static int	entrySize() A header is always a known size.
(package private) long	getLastEntryInPrevFileOffset()
int	getLogSize()
LogEntryType	getLogType() All objects that are reponsible for a generating a type of log entry must implement this.
long	getTransactionId()
boolean	logEntryIsTransactional()
boolean	marshallOutsideWriteLatch() Return true if this item can be marshalled outside the log write latch.
void	postLogWork(long justLoggedLsn) Do any processing we need to do after logging, while under the logging latch.
void	readFromLog(ByteBuffer logBuffer, byte entryTypeVersion) Initialize this object from the data in itemBuf.
String	toString() Print in xml format
(package private) boolean	validate(String fileName, long expectedFileNum)
void	writeToLog(ByteBuffer logBuffer) Serialize this object into the buffer.

Methods inherited from class java.lang.Object

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

Constructor Detail

FileHeader

FileHeader(long fileNum,
           long lastEntryInPrevFileOffset)

FileHeader

public FileHeader()

For logging only.

Method Detail

validate

boolean validate(String fileName,
                 long expectedFileNum)
           throws DatabaseException

Returns:

whether the file header has an old version number.

Throws:

DatabaseException - if the header isn't valid.

getLastEntryInPrevFileOffset

long getLastEntryInPrevFileOffset()

Returns:

the offset of the last entry in the previous file.

getLogType

public LogEntryType getLogType()

Description copied from interface: LoggableObject

All objects that are reponsible for a generating a type of log entry must implement this.

Specified by:

getLogType in interface LoggableObject

Returns:

the type of log entry

See Also:

LoggableObject.getLogType()

marshallOutsideWriteLatch

public boolean marshallOutsideWriteLatch()

Description copied from interface: LoggableObject

Return true if this item can be marshalled outside the log write latch.

Specified by:

marshallOutsideWriteLatch in interface LoggableObject

See Also:

Can be marshalled outside the log write latch.

countAsObsoleteWhenLogged

public boolean countAsObsoleteWhenLogged()

Description copied from interface: LoggableObject

Returns true if this item should be counted as obsoleted when logged. This currently applies to deleted LNs only.

Specified by:

countAsObsoleteWhenLogged in interface LoggableObject

See Also:

LoggableObject.countAsObsoleteWhenLogged()

postLogWork

public void postLogWork(long justLoggedLsn)
                 throws DatabaseException

Description copied from interface: LoggableObject

Do any processing we need to do after logging, while under the logging latch.

Specified by:

postLogWork in interface LoggableObject

Throws:

DatabaseException

See Also:

LoggableObject.postLogWork(long)

entrySize

static int entrySize()

A header is always a known size.

getLogSize

public int getLogSize()

Specified by:

getLogSize in interface LogWritable

Returns:

number of bytes used to store this object

See Also:

LogWritable.getLogSize()

writeToLog

public void writeToLog(ByteBuffer logBuffer)

Description copied from interface: LogWritable

Serialize this object into the buffer.

Specified by:

writeToLog in interface LogWritable

Parameters:

logBuffer - is the destination buffer

See Also:

Serialize this object into the buffer. Update cksum with all the bytes used by this object

readFromLog

public void readFromLog(ByteBuffer logBuffer,
                        byte entryTypeVersion)
                 throws LogException

Description copied from interface: LogReadable

Initialize this object from the data in itemBuf.

Specified by:

readFromLog in interface LogReadable

Parameters:

itemBuf - the source buffer

Throws:

LogException

See Also:

Initialize this object from the data in itemBuf.

dumpLog

public void dumpLog(StringBuffer sb,
                    boolean verbose)

Description copied from interface: LogReadable

Write the object into the string buffer for log dumping. Each object should be dumped without indentation or new lines and should be valid XML.

Specified by:

dumpLog in interface LogReadable

Parameters:

sb - destination string buffer

verbose - if true, dump the full, verbose version

See Also:

LogReadable.dumpLog(java.lang.StringBuffer, boolean)

logEntryIsTransactional

public boolean logEntryIsTransactional()

Specified by:

logEntryIsTransactional in interface LogReadable

Returns:

true if the LogEntry is a transactional log entry type.

See Also:

LogReadable.logEntryIsTransactional()

getTransactionId

public long getTransactionId()

Specified by:

getTransactionId in interface LogReadable

Returns:

return the transaction id if this log entry is transactional, 0 otherwise.

See Also:

LogReadable.getTransactionId()

toString

public String toString()

Print in xml format

Overrides:

toString in class Object