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

Class KeyRangeIntersectionIterator

java.lang.Object

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

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

org.apache.cassandra.index.sai.iterators.KeyRangeIntersectionIterator

All Implemented Interfaces:

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

public class KeyRangeIntersectionIterator
extends KeyRangeIterator

A simple intersection iterator that makes no real attempts at optimising the iteration apart from initially sorting the ranges. This implementation also supports an intersection limit via CassandraRelevantProperties.SAI_INTERSECTION_CLAUSE_LIMIT which limits the number of ranges that will be included in the intersection. This currently defaults to 2.

Intersection only works for ranges that are compatible according to PrimaryKey.Kind.isIntersectable(Kind).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	KeyRangeIntersectionIterator.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

Method Summary

Modifier and Type	Method	Description
static KeyRangeIntersectionIterator.Builder	builder(int size, int limit)
static KeyRangeIntersectionIterator.Builder	builder(int size, int limit, Runnable onClose)
static KeyRangeIntersectionIterator.Builder	builder(int size, Runnable onClose)
void	close()
protected PrimaryKey	computeNext()	Returns the next element.
protected static boolean	isDisjoint(KeyRangeIterator a, KeyRangeIterator b)
protected void	performSkipTo(PrimaryKey nextKey)	Skip to nextKey.

Methods inherited from class org.apache.cassandra.index.sai.iterators.KeyRangeIterator

empty, getMaximum, getMaxKeys, getMinimum, nullSafeMax, nullSafeMin, setOnClose, skipTo

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

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

Method Details

computeNext

protected PrimaryKey computeNext()

Description copied from class: AbstractGuavaIterator

Returns the next element. Note: the implementation must call AbstractGuavaIterator.endOfData() when there are no elements left in the iteration. Failure to do so could result in an infinite loop.

The initial invocation of AbstractGuavaIterator.hasNext() or AbstractGuavaIterator.next() calls this method, as does the first invocation of hasNext or next following each successful call to next. Once the implementation either invokes endOfData or throws an exception, computeNext is guaranteed to never be called again.

If this method throws an exception, it will propagate outward to the hasNext or next invocation that invoked this method. Any further attempts to use the iterator will result in an IllegalStateException.

The implementation of this method may not invoke the hasNext, next, or AbstractGuavaIterator.peek() methods on this instance; if it does, an IllegalStateException will result.

Specified by:

computeNext in class AbstractGuavaIterator<PrimaryKey>

Returns:

the next element if there was one. If endOfData was called during execution, the return value will be ignored.

performSkipTo

protected void performSkipTo(PrimaryKey nextKey)

Description copied from class: KeyRangeIterator

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.

Specified by:

performSkipTo in class KeyRangeIterator

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class KeyRangeIterator

builder

public static KeyRangeIntersectionIterator.Builder builder(int size,
 int limit)

builder

public static KeyRangeIntersectionIterator.Builder builder(int size,
 Runnable onClose)

builder

public static KeyRangeIntersectionIterator.Builder builder(int size,
 int limit,
 Runnable onClose)

isDisjoint

protected static boolean isDisjoint(KeyRangeIterator a,
 KeyRangeIterator b)