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

Class KeyRangeConcatIterator

java.lang.Object

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

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

org.apache.cassandra.index.sai.iterators.KeyRangeConcatIterator

All Implemented Interfaces:

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

public class KeyRangeConcatIterator
extends KeyRangeIterator

KeyRangeConcatIterator takes a list of sorted range iterators and concatenates them, leaving duplicates in place, to produce a new stably sorted iterator. Duplicates are eliminated later in StorageAttachedIndexSearcher as results from multiple SSTable indexes and their respective segments are consumed.

ex. (1, 2, 3) + (3, 3, 4, 5) -> (1, 2, 3, 3, 3, 4, 5) ex. (1, 2, 2, 3) + (3, 4, 4, 6, 6, 7) -> (1, 2, 2, 3, 3, 4, 4, 6, 6, 7)

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	KeyRangeConcatIterator.Builder

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

AbstractGuavaIterator.State

Field Summary

Fields

Modifier and Type	Field	Description
static final String	MUST_BE_SORTED_ERROR

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

next, state

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	KeyRangeConcatIterator(KeyRangeIterator.Builder.Statistics statistics, List<KeyRangeIterator> ranges, Runnable onClose)

Method Summary

Modifier and Type	Method	Description
static KeyRangeConcatIterator.Builder	builder(int size)
static KeyRangeConcatIterator.Builder	builder(int size, Runnable onClose)
void	close()
protected PrimaryKey	computeNext()	Returns the next element.
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

Field Details

MUST_BE_SORTED_ERROR

public static final String MUST_BE_SORTED_ERROR

See Also:

• Constant Field Values

Constructor Details

KeyRangeConcatIterator

protected KeyRangeConcatIterator(KeyRangeIterator.Builder.Statistics statistics,
 List<KeyRangeIterator> ranges,
 Runnable onClose)

Method Details

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

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.

close

public void close()

Specified by:

close in interface AutoCloseable

Specified by:

close in interface Closeable

Overrides:

close in class KeyRangeIterator

builder

public static KeyRangeConcatIterator.Builder builder(int size)

builder

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