com.orientechnologies.orient.core.iterator

Class OIdentifiableIterator<REC extends OIdentifiable>

java.lang.Object

com.orientechnologies.orient.core.iterator.OIdentifiableIterator<REC>

All Implemented Interfaces:

Iterable<REC>, Iterator<REC>

Direct Known Subclasses:

ORecordIteratorCluster, ORecordIteratorClusters

public abstract class OIdentifiableIterator<REC extends OIdentifiable>
extends Object
implements Iterator<REC>, Iterable<REC>

Iterator class to browse forward and backward the records of a cluster. Once browsed in a direction, the iterator cannot change it.

Author:

Luca Garulli (l.garulli--(at)--orientdb.com)

Field Summary

Fields

Modifier and Type	Field and Description
protected Set<ORID>	brokenRIDs Set of RIDs of records which were indicated as broken during cluster iteration.
protected long	browsedRecords
protected ORecordId	current
protected int	currentTxEntryPosition
protected ODatabaseDocumentInternal	database
protected long	firstClusterEntry
protected long	lastClusterEntry
protected long	limit
protected boolean	liveUpdated
protected OStorage.LOCKING_STRATEGY	lockingStrategy
protected long	totalAvailableRecords
protected List<ORecordOperation>	txEntries

Constructor Summary

Constructors

Constructor and Description
OIdentifiableIterator(ODatabaseDocumentInternal iDatabase)
OIdentifiableIterator(ODatabaseDocumentInternal iDatabase, OStorage.LOCKING_STRATEGY iLockingStrategy) Deprecated. usage of this constructor may lead to deadlocks.

Method Summary

Modifier and Type	Method and Description
abstract OIdentifiableIterator<REC>	begin()
protected boolean	checkCurrentPosition()
protected void	checkDirection(boolean iForward)
protected static void	checkForSystemClusters(ODatabaseDocumentInternal iDatabase, int[] iClusterIds)
ORecord	current()
protected long	currentPosition()
Set<ORID>	getBrokenRIDs()
long	getCurrentEntry()
String	getFetchPlan()
long	getLimit() Return the current limit on browsing record.
protected ORecord	getRecord() Return the record to use for the operation.
protected ORecord	getTransactionEntry()
abstract boolean	hasPrevious()
boolean	isLiveUpdated() Return current configuration of live updates.
boolean	isReuseSameRecord() Tells if the iterator is using the same record for browsing.
Iterator<REC>	iterator() Return the iterator to be used in Java5+ constructs for( ORecordDocument rec : database.browseCluster( "Animal" ) ){ ... }
abstract OIdentifiableIterator<REC>	last()
protected boolean	nextPosition()
abstract OIdentifiable	previous()
protected boolean	prevPosition()
protected ORecord	readCurrentRecord(ORecord iRecord, int iMovement) Read the current record and increment the counter if the record was found.
void	remove()
protected void	resetCurrentPosition()
void	setFetchPlan(String fetchPlan)
OIdentifiableIterator<REC>	setLimit(long limit) Set the limit on browsing record.
OIdentifiableIterator<REC>	setLiveUpdated(boolean liveUpdated) Tell to the iterator that the upper limit must be checked at every cycle.
OIdentifiableIterator<REC>	setReuseSameRecord(boolean reuseSameRecord) Tell to the iterator to use the same record for browsing.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.util.Iterator

forEachRemaining, hasNext, next

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Field Detail

database

protected final ODatabaseDocumentInternal database

current

protected final ORecordId current

liveUpdated

protected boolean liveUpdated

limit

protected long limit

browsedRecords

protected long browsedRecords

lockingStrategy

protected OStorage.LOCKING_STRATEGY lockingStrategy

totalAvailableRecords

protected long totalAvailableRecords

txEntries

protected List<ORecordOperation> txEntries

currentTxEntryPosition

protected int currentTxEntryPosition

firstClusterEntry

protected long firstClusterEntry

lastClusterEntry

protected long lastClusterEntry

brokenRIDs

protected final Set<ORID> brokenRIDs

Set of RIDs of records which were indicated as broken during cluster iteration. Mainly used during JSON export/import procedure to fix links on broken records.

Constructor Detail

OIdentifiableIterator

public OIdentifiableIterator(ODatabaseDocumentInternal iDatabase)

OIdentifiableIterator

@Deprecated
public OIdentifiableIterator(ODatabaseDocumentInternal iDatabase,
                                         OStorage.LOCKING_STRATEGY iLockingStrategy)

Deprecated. usage of this constructor may lead to deadlocks.

Method Detail

hasPrevious

public abstract boolean hasPrevious()

previous

public abstract OIdentifiable previous()

begin

public abstract OIdentifiableIterator<REC> begin()

last

public abstract OIdentifiableIterator<REC> last()

current

public ORecord current()

getFetchPlan

public String getFetchPlan()

getBrokenRIDs

public Set<ORID> getBrokenRIDs()

setFetchPlan

public void setFetchPlan(String fetchPlan)

remove

public void remove()

Specified by:

remove in interface Iterator<REC extends OIdentifiable>

isReuseSameRecord

public boolean isReuseSameRecord()

Tells if the iterator is using the same record for browsing.

See Also:

setReuseSameRecord(boolean)

setReuseSameRecord

public OIdentifiableIterator<REC> setReuseSameRecord(boolean reuseSameRecord)

Tell to the iterator to use the same record for browsing. The record will be reset before every use. This improve the performance and reduce memory utilization since it does not create a new one for each operation, but pay attention to copy the data of the record once read otherwise they will be reset to the next operation.

Parameters:

reuseSameRecord - if true the same record will be used for iteration. If false new record will be created each time iterator retrieves record from db.

Returns:

@see #isReuseSameRecord()

getCurrentEntry

public long getCurrentEntry()

iterator

public Iterator<REC> iterator()

Return the iterator to be used in Java5+ constructs

for( ORecordDocument rec : database.browseCluster( "Animal" ) ){
...
}


Specified by:

iterator in interface Iterable<REC extends OIdentifiable>

getLimit

public long getLimit()

Return the current limit on browsing record. -1 means no limits (default).

Returns:

The limit if setted, otherwise -1

See Also:

setLimit(long)

setLimit

public OIdentifiableIterator<REC> setLimit(long limit)

Set the limit on browsing record. -1 means no limits. You can set the limit even while you're browsing.

Parameters:

limit - The current limit on browsing record. -1 means no limits (default).

See Also:

getLimit()

isLiveUpdated

public boolean isLiveUpdated()

Return current configuration of live updates.

Returns:

True to activate it, otherwise false (default)

See Also:

setLiveUpdated(boolean)

setLiveUpdated

public OIdentifiableIterator<REC> setLiveUpdated(boolean liveUpdated)

Tell to the iterator that the upper limit must be checked at every cycle. Useful when concurrent deletes or additions change the size of the cluster while you're browsing it. Default is false.

Parameters:

liveUpdated - True to activate it, otherwise false (default)

See Also:

isLiveUpdated()

getTransactionEntry

protected ORecord getTransactionEntry()

getRecord

protected ORecord getRecord()

Return the record to use for the operation.

Returns:

the record to use for the operation.

checkDirection

protected void checkDirection(boolean iForward)

readCurrentRecord

protected ORecord readCurrentRecord(ORecord iRecord,
                                    int iMovement)

Read the current record and increment the counter if the record was found.

Parameters:

iRecord - to read value from database inside it. If record is null link will be created and stored in it.

Returns:

record which was read from db.

nextPosition

protected boolean nextPosition()

checkCurrentPosition

protected boolean checkCurrentPosition()

prevPosition

protected boolean prevPosition()

resetCurrentPosition

protected void resetCurrentPosition()

currentPosition

protected long currentPosition()

checkForSystemClusters

protected static void checkForSystemClusters(ODatabaseDocumentInternal iDatabase,
                                             int[] iClusterIds)