Package org.apache.cassandra.db

Class Slices

java.lang.Object

org.apache.cassandra.db.Slices

All Implemented Interfaces:

java.lang.Iterable<Slice>

public abstract class Slices
extends java.lang.Object
implements java.lang.Iterable<Slice>

Represents the selection of multiple range of rows within a partition.

A Slices is basically a list of Slice, though those are guaranteed to be non-overlapping and always in clustering order.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Slices.Builder	Builder to create Slices objects.
static interface	Slices.InOrderTester	In simple object that allows to test the inclusion of rows in those slices assuming those rows are passed (to Slices.InOrderTester.includes(org.apache.cassandra.db.Clustering<?>)) in clustering order (or reverse clustering ordered, depending on the argument passed to inOrderTester(boolean)).
static class	Slices.Serializer

Field Summary

Fields

Modifier and Type	Field	Description
static Slices	ALL	Slices selecting all the rows of a partition.
static Slices	NONE	Slices selecting no rows in a partition.
static Slices.Serializer	serializer

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	Slices()

Method Summary

Modifier and Type	Method	Description
ClusteringBound<?>	end()
abstract Slices	forPaging(ClusteringComparator comparator, Clustering<?> lastReturned, boolean inclusive, boolean reversed)	Returns slices for continuing the paging of those slices given the last returned clustering prefix.
abstract Slice	get(int i)	Returns the ith slice of this Slices object.
abstract boolean	hasLowerBound()	Whether the slices instance has a lower bound, that is whether it's first slice start is Slice.BOTTOM.
abstract boolean	hasUpperBound()	Whether the slices instance has an upper bound, that is whether it's last slice end is Slice.TOP.
abstract Slices.InOrderTester	inOrderTester(boolean reversed)	An object that allows to test whether rows are selected by this Slices objects assuming those rows are tested in clustering order.
abstract boolean	intersects(Slice slice)	Checks whether any of the slices intersects witht the given one.
boolean	isEmpty()	Checks if this Slices is empty.
abstract boolean	selects(Clustering<?> clustering)	Whether a given clustering (row) is selected by this Slices object.
abstract int	size()	The number of slice this object contains.
ClusteringBound<?>	start()
abstract java.lang.String	toCQLString(TableMetadata metadata, RowFilter rowFilter)
static Slices	with(ClusteringComparator comparator, Slice slice)	Creates a Slices object that contains a single slice.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, iterator, spliterator

Field Detail

serializer

public static final Slices.Serializer serializer

ALL

public static final Slices ALL

Slices selecting all the rows of a partition.

NONE

public static final Slices NONE

Slices selecting no rows in a partition.

Constructor Detail

Slices

protected Slices()

Method Detail

with

public static Slices with(ClusteringComparator comparator,
                          Slice slice)

Creates a Slices object that contains a single slice.

Parameters:

comparator - the comparator for the table slice is a slice of.

slice - the single slice that the return object should contain.

Returns:

the newly created Slices object.

hasLowerBound

public abstract boolean hasLowerBound()

Whether the slices instance has a lower bound, that is whether it's first slice start is Slice.BOTTOM.

Returns:

whether this slices instance has a lower bound.

hasUpperBound

public abstract boolean hasUpperBound()

Whether the slices instance has an upper bound, that is whether it's last slice end is Slice.TOP.

Returns:

whether this slices instance has an upper bound.

size

public abstract int size()

The number of slice this object contains.

Returns:

the number of slice this object contains.

get

public abstract Slice get(int i)

Returns the ith slice of this Slices object.

Returns:

the ith slice of this object.

start

public ClusteringBound<?> start()

end

public ClusteringBound<?> end()

forPaging

public abstract Slices forPaging(ClusteringComparator comparator,
                                 Clustering<?> lastReturned,
                                 boolean inclusive,
                                 boolean reversed)

Returns slices for continuing the paging of those slices given the last returned clustering prefix.

Parameters:

comparator - the comparator for the table this is a filter for.

lastReturned - the last clustering that was returned for the query we are paging for. The resulting slices will be such that only results coming stricly after lastReturned are returned (where coming after means "greater than" if !reversed and "lesser than" otherwise).

inclusive - whether we want to include the lastReturned in the newly returned page of results.

reversed - whether the query we're paging for is reversed or not.

Returns:

new slices that select results coming after lastReturned.

inOrderTester

public abstract Slices.InOrderTester inOrderTester(boolean reversed)

An object that allows to test whether rows are selected by this Slices objects assuming those rows are tested in clustering order.

Parameters:

reversed - if true, the rows passed to the returned object will be assumed to be in reversed clustering order, otherwise they should be in clustering order.

Returns:

an object that tests for selection of rows by this Slices object.

selects

public abstract boolean selects(Clustering<?> clustering)

Whether a given clustering (row) is selected by this Slices object.

Parameters:

clustering - the clustering to test for selection.

Returns:

whether a given clustering (row) is selected by this Slices object.

intersects

public abstract boolean intersects(Slice slice)

Checks whether any of the slices intersects witht the given one.

Returns:

true if there exists a slice which (Slice.intersects(ClusteringComparator, Slice)) with the provided slice

toCQLString

public abstract java.lang.String toCQLString(TableMetadata metadata,
                                             RowFilter rowFilter)

isEmpty

public final boolean isEmpty()

Checks if this Slices is empty.

Returns:

true if this Slices is empty, false otherwise.