Package org.apache.cassandra.db.rows

Class LazilyInitializedUnfilteredRowIterator

java.lang.Object

org.apache.cassandra.utils.AbstractIterator<Unfiltered>

org.apache.cassandra.db.rows.LazilyInitializedUnfilteredRowIterator

All Implemented Interfaces:

com.google.common.collect.PeekingIterator<Unfiltered>, AutoCloseable, Iterator<Unfiltered>, BaseRowIterator<Unfiltered>, UnfilteredRowIterator, CloseableIterator<Unfiltered>

Direct Known Subclasses:

UnfilteredRowIteratorWithLowerBound

public abstract class LazilyInitializedUnfilteredRowIterator
extends AbstractIterator<Unfiltered>
implements UnfilteredRowIterator

Abstract class to create UnfilteredRowIterator that lazily initializes itself.

This is used during partition range queries when we know the partition key but want to defer the initialization of the rest of the UnfilteredRowIterator until we need it.

Constructor Summary

Constructors

Constructor	Description
LazilyInitializedUnfilteredRowIterator(DecoratedKey partitionKey)

Method Summary

Modifier and Type	Method	Description
void	close()
RegularAndStaticColumns	columns()	A subset of the columns for the (static and regular) rows returned by this iterator.
protected Unfiltered	computeNext()
protected abstract UnfilteredRowIterator	initializeIterator()
boolean	isOpen()
boolean	isReverseOrder()	Whether or not the rows returned by this iterator are in reversed clustering order.
protected void	maybeInit()
TableMetadata	metadata()	The metadata for the table this iterator on.
DecoratedKey	partitionKey()	The partition key of the partition this in an iterator over.
DeletionTime	partitionLevelDeletion()	The partition level deletion for the partition this iterate over.
Row	staticRow()	The static part corresponding to this partition (this can be an empty row but cannot be null).
EncodingStats	stats()	Return "statistics" about what is returned by this iterator.

Methods inherited from class org.apache.cassandra.utils.AbstractIterator

endOfData, hasNext, next, peek, remove

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

Methods inherited from interface org.apache.cassandra.db.rows.UnfilteredRowIterator

isEmpty

Constructor Details

LazilyInitializedUnfilteredRowIterator

public LazilyInitializedUnfilteredRowIterator(DecoratedKey partitionKey)

Method Details

initializeIterator

protected abstract UnfilteredRowIterator initializeIterator()

maybeInit

protected void maybeInit()

metadata

public TableMetadata metadata()

Description copied from interface: BaseRowIterator

The metadata for the table this iterator on.

Specified by:

metadata in interface BaseRowIterator<Unfiltered>

columns

public RegularAndStaticColumns columns()

Description copied from interface: BaseRowIterator

A subset of the columns for the (static and regular) rows returned by this iterator. Every row returned by this iterator must guarantee that it has only those columns.

Specified by:

columns in interface BaseRowIterator<Unfiltered>

isReverseOrder

public boolean isReverseOrder()

Description copied from interface: BaseRowIterator

Whether or not the rows returned by this iterator are in reversed clustering order.

Specified by:

isReverseOrder in interface BaseRowIterator<Unfiltered>

partitionKey

public DecoratedKey partitionKey()

Description copied from interface: BaseRowIterator

The partition key of the partition this in an iterator over.

Specified by:

partitionKey in interface BaseRowIterator<Unfiltered>

partitionLevelDeletion

public DeletionTime partitionLevelDeletion()

Description copied from interface: UnfilteredRowIterator

The partition level deletion for the partition this iterate over.

Specified by:

partitionLevelDeletion in interface UnfilteredRowIterator

staticRow

public Row staticRow()

Description copied from interface: BaseRowIterator

The static part corresponding to this partition (this can be an empty row but cannot be null).

Specified by:

staticRow in interface BaseRowIterator<Unfiltered>

stats

public EncodingStats stats()

Description copied from interface: UnfilteredRowIterator

Return "statistics" about what is returned by this iterator. Those are used for performance reasons (for delta-encoding for instance) and code should not expect those to be exact.

Specified by:

stats in interface UnfilteredRowIterator

computeNext

protected Unfiltered computeNext()

Specified by:

computeNext in class AbstractIterator<Unfiltered>

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface CloseableIterator<Unfiltered>

Overrides:

close in class AbstractIterator<Unfiltered>

isOpen

public boolean isOpen()