org.egothor.lock.server
Class LockServerThread.LockServerRecord

java.lang.Object
  org.egothor.lock.server.LockServerThread.LockServerRecord

Enclosing class:

LockServerThread

public class LockServerThread.LockServerRecord
extends java.lang.Object

Record of single location, holds information about lock in it and reservations.

Nested Class Summary

class	LockServerThread.LockServerRecord.LockEntry
class	LockServerThread.LockServerRecord.ReservationEntry

Field Summary

protected java.util.LinkedList<LockServerThread.LockServerRecord.LockEntry>

lockEntryList list of lock entries (locks) that are present in one location

Constructor Summary

LockServerThread.LockServerRecord(java.lang.String location)

Method Summary

boolean	addLockEntry(long lockId, LockType lockType, long expirationTime)
LockResult	addReservationEntry(LockType lockType, long reservationExpirationTime, boolean addFirst)
boolean	containsValidOrExpiredLock(long validationTime) Finds out if entries contains valid lock entry in comparison to time expiration or if there is any expired write or read lock (that means thread crashed and index is in incosistent state).
boolean	containsValidReservation(long now) Checks reservation for a valid one.
LockServerThread.LockServerRecord.LockEntry	getFirstLockEntry(long validationTime) Either set of read locks is present or one single write lock, so this method returns a fine representant.
LockServerThread.LockServerRecord.LockEntry	getLockEntryWithId(long lockId)
long	getLockExpirationTime()
int	indexOfReservation(long reservationId, LockType lockType)
boolean	isWLReservationPreceedingThisOne(int reservationIndex) Checks if there is a write lock reservation in the reservation list that precedes the one with input index.
void	removeFirstReservation()
void	removeLockEntry(LockServerThread.LockServerRecord.LockEntry lockEntry)
void	removeReservation(int index)
int	sizeOfReservationList()

Methods inherited from class java.lang.Object

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

Field Detail

lockEntryList

protected java.util.LinkedList<LockServerThread.LockServerRecord.LockEntry> lockEntryList

list of lock entries (locks) that are present in one location

Constructor Detail

LockServerThread.LockServerRecord

public LockServerThread.LockServerRecord(java.lang.String location)

Method Detail

addLockEntry

public boolean addLockEntry(long lockId,
                            LockType lockType,
                            long expirationTime)

Parameters:

lockId -

lockType -

expirationTime -

removeLockEntry

public void removeLockEntry(LockServerThread.LockServerRecord.LockEntry lockEntry)

Parameters:

lockEntry -

containsValidOrExpiredLock

public boolean containsValidOrExpiredLock(long validationTime)

Finds out if entries contains valid lock entry in comparison to time expiration or if there is any expired write or read lock (that means thread crashed and index is in incosistent state). If it finds any expired lock, it launches recovery process in that location.

Parameters:

validationTime -

Returns:

getFirstLockEntry

public LockServerThread.LockServerRecord.LockEntry getFirstLockEntry(long validationTime)

Either set of read locks is present or one single write lock, so this method returns a fine representant.

Parameters:

validationTime -

Returns:

getLockEntryWithId

public LockServerThread.LockServerRecord.LockEntry getLockEntryWithId(long lockId)

Parameters:

lockId -

Returns:

getLockExpirationTime

public long getLockExpirationTime()

Returns:

containsValidReservation

public boolean containsValidReservation(long now)

Checks reservation for a valid one. It discards the invalid ones.

Parameters:

lockRecord -

now -

Returns:

addReservationEntry

public LockResult addReservationEntry(LockType lockType,
                                      long reservationExpirationTime,
                                      boolean addFirst)

Parameters:

lockRecord -

lockType -

reservationExpirationTime -

Returns:

isWLReservationPreceedingThisOne

public boolean isWLReservationPreceedingThisOne(int reservationIndex)

Checks if there is a write lock reservation in the reservation list that precedes the one with input index.

Parameters:

reservationIndex -

Returns:

indexOfReservation

public int indexOfReservation(long reservationId,
                              LockType lockType)

sizeOfReservationList

public int sizeOfReservationList()

removeFirstReservation

public void removeFirstReservation()

removeReservation

public void removeReservation(int index)