Package org.apache.cassandra.index.sai.iterators

Class KeyRangeIterator

java.lang.Object

org.apache.cassandra.utils.AbstractGuavaIterator<PrimaryKey>

org.apache.cassandra.index.sai.iterators.KeyRangeIterator

All Implemented Interfaces:

com.google.common.collect.PeekingIterator<PrimaryKey>, Closeable, AutoCloseable, Iterator<PrimaryKey>

Direct Known Subclasses:

IndexSearchResultIterator, InMemoryKeyRangeIterator, KeyRangeConcatIterator, KeyRangeIntersectionIterator, KeyRangeUnionIterator, PostingListRangeIterator

@NotThreadSafe
public abstract class KeyRangeIterator
extends AbstractGuavaIterator<PrimaryKey>
implements Closeable

An abstract implementation of AbstractGuavaIterator that supports the building and management of concatanation, union and intersection iterators.

Range iterators contain primary keys, in sorted order, with no duplicates. They also know their minimum and maximum keys, and an upper bound on the number of keys they contain.

Only certain methods are designed to be overriden. The others are marked private or final.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	KeyRangeIterator.Builder

Nested classes/interfaces inherited from class org.apache.cassandra.utils.AbstractGuavaIterator

AbstractGuavaIterator.State

Field Summary

Fields inherited from class org.apache.cassandra.utils.AbstractGuavaIterator

next, state

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	KeyRangeIterator(KeyRangeIterator.Builder.Statistics statistics, Runnable onClose)
	KeyRangeIterator(KeyRangeIterator range, Runnable onClose)
	KeyRangeIterator(PrimaryKey min, PrimaryKey max, long count)
	KeyRangeIterator(PrimaryKey min, PrimaryKey max, long count, Runnable onClose)

Method Summary

Modifier and Type	Method	Description
void	close()
static KeyRangeIterator	empty()
final PrimaryKey	getMaximum()
final long	getMaxKeys()
final PrimaryKey	getMinimum()
protected static PrimaryKey	nullSafeMax(PrimaryKey a, PrimaryKey b)
protected static PrimaryKey	nullSafeMin(PrimaryKey a, PrimaryKey b)
protected abstract void	performSkipTo(PrimaryKey nextKey)	Skip to nextKey.
void	setOnClose(Runnable onClose)
final void	skipTo(PrimaryKey nextKey)	When called, this iterator's current position will be skipped forwards until finding either: 1) an element equal to or bigger than nextKey 2) the end of the iterator

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

computeNext, endOfData, hasNext, next, peek, remove, tryToComputeNext

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

Constructor Details

KeyRangeIterator

protected KeyRangeIterator(KeyRangeIterator.Builder.Statistics statistics,
 Runnable onClose)

KeyRangeIterator

public KeyRangeIterator(KeyRangeIterator range,
 Runnable onClose)

KeyRangeIterator

public KeyRangeIterator(PrimaryKey min,
 PrimaryKey max,
 long count)

KeyRangeIterator

public KeyRangeIterator(PrimaryKey min,
 PrimaryKey max,
 long count,
 Runnable onClose)

Method Details

getMinimum

public final PrimaryKey getMinimum()

getMaximum

public final PrimaryKey getMaximum()

getMaxKeys

public final long getMaxKeys()

Returns:

an upper bound on the number of keys that can be returned by this iterator.

skipTo

public final void skipTo(PrimaryKey nextKey)

When called, this iterator's current position will be skipped forwards until finding either: 1) an element equal to or bigger than nextKey 2) the end of the iterator

Parameters:

nextKey - value to skip the iterator forward until matching

performSkipTo

protected abstract void performSkipTo(PrimaryKey nextKey)

Skip to nextKey.

That is, implementations should set up the iterator state such that calling computeNext() will return nextKey if present, or the first one after it if not present.

setOnClose

public void setOnClose(Runnable onClose)

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

empty

public static KeyRangeIterator empty()

nullSafeMin

protected static PrimaryKey nullSafeMin(PrimaryKey a,
 PrimaryKey b)

nullSafeMax

protected static PrimaryKey nullSafeMax(PrimaryKey a,
 PrimaryKey b)