com.sleepycat.je.log
Class FileHeader

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

All Implemented Interfaces:

Loggable

public class FileHeader
extends Object
implements Loggable

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

void	dumpLog(StringBuilder sb, boolean verbose) Write the object into the string buffer for log dumping.
static int	entrySize() A header is always a known size.
(package private) long	getLastEntryInPrevFileOffset()
int	getLogSize()
int	getLogVersion()
long	getTransactionId()
boolean	logicalEquals(Loggable other)
void	readFromLog(ByteBuffer logBuffer, int unusableEntryVersion) Initialize this object from the data in itemBuf.
String	toString() Print in xml format
(package private) int	validate(EnvironmentImpl envImpl, 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

getLogVersion

public int getLogVersion()

validate

int validate(EnvironmentImpl envImpl,
             String fileName,
             long expectedFileNum)
       throws DatabaseException

Returns:

file header log version.

Throws:

DatabaseException

getLastEntryInPrevFileOffset

long getLastEntryInPrevFileOffset()

Returns:

the offset of the last entry in the previous file.

entrySize

public static int entrySize()

A header is always a known size.

getLogSize

public int getLogSize()

Specified by:

getLogSize in interface Loggable

Returns:

number of bytes used to store this object

See Also:

Loggable.getLogSize()

writeToLog

public void writeToLog(ByteBuffer logBuffer)

Description copied from interface: Loggable

Serialize this object into the buffer.

Specified by:

writeToLog in interface Loggable

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,
                        int unusableEntryVersion)

Description copied from interface: Loggable

Initialize this object from the data in itemBuf.

Specified by:

readFromLog in interface Loggable

Parameters:

itemBuf - the source buffer

See Also:

Initialize this object from the data in itemBuf.

dumpLog

public void dumpLog(StringBuilder sb,
                    boolean verbose)

Description copied from interface: Loggable

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 Loggable

Parameters:

sb - destination string buffer

verbose - if true, dump the full, verbose version

See Also:

Loggable.dumpLog(java.lang.StringBuilder, boolean)

getTransactionId

public long getTransactionId()

Specified by:

getTransactionId in interface Loggable

Returns:

the transaction id embedded within this loggable object. Objects that have no transaction id should return 0.

See Also:

Loggable.getTransactionId()

logicalEquals

public boolean logicalEquals(Loggable other)

Specified by:

logicalEquals in interface Loggable

Returns:

true if these two loggable items are logically the same. Used for replication testing.

See Also:

Always return false, this item should never be compared.

toString

public String toString()

Print in xml format

Overrides:

toString in class Object