com.sleepycat.je.log.entry

Class NameLNLogEntry

java.lang.Object

com.sleepycat.je.log.entry.BaseEntry

com.sleepycat.je.log.entry.LNLogEntry

com.sleepycat.je.log.entry.NameLNLogEntry

All Implemented Interfaces:

LogEntry, NodeLogEntry, java.lang.Cloneable

public class NameLNLogEntry
extends LNLogEntry

NameLNLogEntry contains all the regular LNLogEntry fields and additional information about the database operation which instigated the logging of this NameLN. This additional information is used to support replication of database operations in a replication group. Database operations pose a special problem for replication because unlike data record put and get calls, they can result in multiple log entries that are not all members of a single transaction. Create and truncate are the problem operations because they end up logging new MapLNs, and our implementation does not treat MapLNs as transactional. Database operations challenge two replication assumptions: (a) that all logical operations can be repeated on the client node based on the contents of a single log entry, and (b) that non-txnal log entries like MapLNs need not be replicated. Specifically, here's what is logged for database operations. create: 1. new NameLN_TX 2. new MapLN, which has the database config info. 3. txn commit of autocommit or user txn. rename: 1. deleted NameLN_TX 2. new NameLN_TX 3. txn commit from autocommit or user txn truncate: 1. new MapLN w/new id 2. modify the existing NameLN with new id (old database is deleted by usual commit-time processing) 3. txn commit from autocommit or user txn delete 1. deleted NameLN_TX (old database gets deleted by usual commit-time processing) 2. txn commit from autocommit or user txn Extra information is needed for create and truncate, which both log information within the MapLN. Rename and delete only log NameLNs, so they can be replicated on the client using the normal replication messages. The extra fields which follow the usual LNLogEntry fields are: operationType - the type of database operation. In a single node system, this is local information implicit in the code path. databaseConfig (optional) - For creates, database configuration info databaseId (optional)- For truncates, the old db id, so we know which MapLN to delete.

Field Summary

Fields inherited from class com.sleepycat.je.log.entry.BaseEntry

entryType, logClass

Constructor Summary

Constructors

Constructor and Description
NameLNLogEntry() Constructor to read an entry.
NameLNLogEntry(LogEntryType entryType, NameLN nameLN, DatabaseId dbId, byte[] key, long abortLsn, boolean abortKnownDeleted, Txn txn, ReplicationContext repContext) Constructor to write this entry.

Method Summary

Methods

Modifier and Type	Method and Description
java.lang.StringBuffer	dumpEntry(java.lang.StringBuffer sb, boolean verbose) Extends its super class to dump database operation information.
DbOperationType	getOperationType()
ReplicatedDatabaseConfig	getReplicatedCreateConfig()
int	getSize() Extends its super class to add in database operation information.
DatabaseId	getTruncateOldDbId()
boolean	logicalEquals(LogEntry other)
void	readEntry(LogEntryHeader header, java.nio.ByteBuffer entryBuffer, boolean readFullItem) Extends its super class to read in database operation information.
void	writeEntry(LogEntryHeader header, java.nio.ByteBuffer destBuffer) Extends its super class to add in database operation information.

Methods inherited from class com.sleepycat.je.log.entry.LNLogEntry

clone, countAsObsoleteWhenLogged, getAbortKnownDeleted, getAbortLsn, getDbId, getDupKey, getKey, getLastLoggedSize, getLN, getMainItem, getNodeId, getTransactionId, getTxnId, getUserTxn, postLogWork

Methods inherited from class com.sleepycat.je.log.entry.BaseEntry

getLogType, setLogType, toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface com.sleepycat.je.log.entry.LogEntry

getLogType, setLogType

Constructor Detail

NameLNLogEntry

public NameLNLogEntry()

Constructor to read an entry.

NameLNLogEntry

public NameLNLogEntry(LogEntryType entryType,
              NameLN nameLN,
              DatabaseId dbId,
              byte[] key,
              long abortLsn,
              boolean abortKnownDeleted,
              Txn txn,
              ReplicationContext repContext)

Constructor to write this entry.

Method Detail

readEntry

public void readEntry(LogEntryHeader header,
             java.nio.ByteBuffer entryBuffer,
             boolean readFullItem)
               throws DatabaseException

Extends its super class to read in database operation information.

Specified by:

readEntry in interface LogEntry

Overrides:

readEntry in class LNLogEntry

Throws:

DatabaseException

See Also:

LNLogEntry.readEntry(com.sleepycat.je.log.LogEntryHeader, java.nio.ByteBuffer, boolean)

dumpEntry

public java.lang.StringBuffer dumpEntry(java.lang.StringBuffer sb,
                               boolean verbose)

Extends its super class to dump database operation information.

Specified by:

dumpEntry in interface LogEntry

Overrides:

dumpEntry in class LNLogEntry

See Also:

LNLogEntry.dumpEntry(java.lang.StringBuffer, boolean)

getSize

public int getSize()

Extends its super class to add in database operation information.

Specified by:

getSize in interface LogEntry

Overrides:

getSize in class LNLogEntry

Returns:

size of byte buffer needed to store this entry.

See Also:

LNLogEntry.getSize()

writeEntry

public void writeEntry(LogEntryHeader header,
              java.nio.ByteBuffer destBuffer)

Extends its super class to add in database operation information.

Specified by:

writeEntry in interface LogEntry

Overrides:

writeEntry in class LNLogEntry

destBuffer - is the destination buffer

See Also:

LogEntry#writeToLog

logicalEquals

public boolean logicalEquals(LogEntry other)

Specified by:

logicalEquals in interface LogEntry

Overrides:

logicalEquals in class LNLogEntry

Returns:

true if these two log entries are logically the same. Used for replication.

See Also:

LogEntry.logicalEquals(com.sleepycat.je.log.entry.LogEntry)

getOperationType

public DbOperationType getOperationType()

Returns:

the operationType

getReplicatedCreateConfig

public ReplicatedDatabaseConfig getReplicatedCreateConfig()

Returns:

the replicatedCreateConfig

getTruncateOldDbId

public DatabaseId getTruncateOldDbId()

Returns:

the truncateOldDbId