org.apache.cassandra.db.compaction

Class LazilyCompactedRow

java.lang.Object

org.apache.cassandra.db.compaction.AbstractCompactedRow

org.apache.cassandra.db.compaction.LazilyCompactedRow

All Implemented Interfaces:

java.io.Closeable, java.lang.AutoCloseable, java.lang.Iterable<OnDiskAtom>

public class LazilyCompactedRow
extends AbstractCompactedRow
implements java.lang.Iterable<OnDiskAtom>

LazilyCompactedRow only computes the row bloom filter and column index in memory (at construction time); it does this by reading one column at a time from each of the rows being compacted, and merging them as it does so. So the most we have in memory at a time is the bloom filter, the index, and one column from each pre-compaction row.

Field Summary

Fields inherited from class org.apache.cassandra.db.compaction.AbstractCompactedRow

key

Constructor Summary

Constructors

Constructor and Description
LazilyCompactedRow(CompactionController controller, java.util.List<? extends OnDiskAtomIterator> rows)

Method Summary

Methods

Modifier and Type	Method and Description
void	close()
ColumnStats	columnStats()
AbstractType<?>	getComparator()
java.util.Iterator<OnDiskAtom>	iterator()
void	update(java.security.MessageDigest digest) update @param digest with the data bytes of the row (not including row key or row size).
RowIndexEntry	write(long currentPosition, java.io.DataOutput out) write the row (size + column index + filter + column data, but NOT row key) to @param out.

Methods inherited from class java.lang.Object

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

Constructor Detail

LazilyCompactedRow

public LazilyCompactedRow(CompactionController controller,
                  java.util.List<? extends OnDiskAtomIterator> rows)

Method Detail

write

public RowIndexEntry write(long currentPosition,
                  java.io.DataOutput out)
                    throws java.io.IOException

Description copied from class: AbstractCompactedRow

write the row (size + column index + filter + column data, but NOT row key) to @param out. write() may change internal state; it is NOT valid to call write() or update() a second time.

Specified by:

write in class AbstractCompactedRow

Returns:

index information for the written row, or null if the compaction resulted in only expired tombstones.

Throws:

java.io.IOException

update

public void update(java.security.MessageDigest digest)

Description copied from class: AbstractCompactedRow

update @param digest with the data bytes of the row (not including row key or row size). May be called even if empty. update() may change internal state; it is NOT valid to call write() or update() a second time.

Specified by:

update in class AbstractCompactedRow

getComparator

public AbstractType<?> getComparator()

iterator

public java.util.Iterator<OnDiskAtom> iterator()

Specified by:

iterator in interface java.lang.Iterable<OnDiskAtom>

columnStats

public ColumnStats columnStats()

Specified by:

columnStats in class AbstractCompactedRow

Returns:

aggregate information about the columns in this row. Some fields may contain default values if computing them value would require extra effort we're not willing to make.

close

public void close()

Specified by:

close in interface java.io.Closeable

Specified by:

close in interface java.lang.AutoCloseable