Package org.apache.cassandra.index.sasi.utils

Class RangeIntersectionIterator.LookupIntersectionIterator<K extends Comparable<K>,D extends CombinedValue<K>>

java.lang.Object

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

org.apache.cassandra.index.sasi.utils.RangeIterator<K,D>

org.apache.cassandra.index.sasi.utils.RangeIntersectionIterator.LookupIntersectionIterator<K,D>

Type Parameters:

K - The type used to sort ranges.

D - The container type which is going to be returned by Iterator.next().

All Implemented Interfaces:

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

Enclosing class:

RangeIntersectionIterator

protected static class RangeIntersectionIterator.LookupIntersectionIterator<K extends Comparable<K>,D extends CombinedValue<K>>
extends RangeIterator<K,D>

Iterator which performs a linear scan over a primary range (the smallest of the ranges) and O(log(n)) lookup into secondary ranges using values from the primary iterator. This technique is efficient when one of the intersection ranges is smaller than others e.g. ratio 0.01d (default), in such situation scan + lookup is more efficient comparing to "bounce" merge because "bounce" distance is never going to be big.

Nested Class Summary

Nested classes/interfaces inherited from class org.apache.cassandra.index.sasi.utils.RangeIterator

RangeIterator.Builder<K extends Comparable<K>,D extends CombinedValue<K>>

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

AbstractGuavaIterator.State

Field Summary

Fields

Modifier and Type	Field	Description
protected final PriorityQueue<RangeIterator<K,D>>	ranges

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

next, state

Method Summary

Modifier and Type	Method	Description
void	close()
protected D	computeNext()	Returns the next element.
protected void	performSkipTo(K nextToken)

Methods inherited from class org.apache.cassandra.index.sasi.utils.RangeIterator

getCount, getCurrent, getMaximum, getMinimum, isOverlapping, isOverlapping, recomputeNext, skipTo, tryToComputeNext

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

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

Field Details

ranges

protected final PriorityQueue<RangeIterator<K extends Comparable<K>,D extends CombinedValue<K>>> ranges

Method Details

computeNext

protected D 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<D extends CombinedValue<K>>

Returns:

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

performSkipTo

protected void performSkipTo(K nextToken)

Specified by:

performSkipTo in class RangeIterator<K extends Comparable<K>,D extends CombinedValue<K>>

close

public void close()
           throws IOException

Throws:

IOException