Package org.apache.cassandra.db

Class Slice

java.lang.Object

org.apache.cassandra.db.Slice

public class Slice
extends java.lang.Object

A slice represents the selection of a range of rows.

A slice has a start and an end bound that are both (potentially full) clustering prefixes. A slice selects every row whose clustering is included within its start and end bounds. Both start and end can be either inclusive or exclusive.

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static class	Slice.Serializer

Field Summary

Fields

Modifier and Type	Field	Description
static Slice	ALL	The slice selecting all rows (of a given partition)
static Slice.Serializer	serializer

Method Summary

Modifier and Type	Method	Description
ClusteringBound<?>	close(boolean reversed)
ClusteringBound<?>	end()
boolean	equals(java.lang.Object other)
Slice	forPaging(ClusteringComparator comparator, Clustering<?> lastReturned, boolean inclusive, boolean reversed)	Returns a slice for continuing paging from the last returned clustering prefix.
int	hashCode()
boolean	includes(ClusteringComparator comparator, ClusteringPrefix<?> bound)	Returns whether a given clustering or bound is included in this slice.
boolean	intersects(ClusteringComparator comparator, Slice other)	Whether this slice and the provided slice intersects.
boolean	isEmpty(ClusteringComparator comparator)	Return whether the slice is empty.
static boolean	isEmpty(ClusteringComparator comparator, ClusteringBound<?> start, ClusteringBound<?> end)	Return whether the slice formed by the two provided bound is empty or not.
static Slice	make(Clustering<?> clustering)	Makes a slice covering a single clustering
static Slice	make(Clustering<?> start, Clustering<?> end)	Makes a slice covering a range from start to end clusterings, with both start and end included
static Slice	make(ClusteringBound<?> start, ClusteringBound<?> end)
static Slice	make(ClusteringBoundOrBoundary<?> start, ClusteringBoundOrBoundary<?> end)	Makes a slice for the given bounds
static Slice	make(ClusteringComparator comparator, java.lang.Object... values)
ClusteringBound<?>	open(boolean reversed)
ClusteringBound<?>	start()
java.lang.String	toString(ClusteringComparator comparator)

Methods inherited from class java.lang.Object

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

Field Detail

serializer

public static final Slice.Serializer serializer

ALL

public static final Slice ALL

The slice selecting all rows (of a given partition)

Method Detail

make

public static Slice make(ClusteringBound<?> start,
                         ClusteringBound<?> end)

make

public static Slice make(ClusteringComparator comparator,
                         java.lang.Object... values)

make

public static Slice make(Clustering<?> clustering)

Makes a slice covering a single clustering

make

public static Slice make(Clustering<?> start,
                         Clustering<?> end)

Makes a slice covering a range from start to end clusterings, with both start and end included

make

public static Slice make(ClusteringBoundOrBoundary<?> start,
                         ClusteringBoundOrBoundary<?> end)

Makes a slice for the given bounds

start

public ClusteringBound<?> start()

end

public ClusteringBound<?> end()

open

public ClusteringBound<?> open(boolean reversed)

close

public ClusteringBound<?> close(boolean reversed)

isEmpty

public boolean isEmpty(ClusteringComparator comparator)

Return whether the slice is empty.

Parameters:

comparator - the comparator to compare the bounds.

Returns:

whether the slice formed is empty or not.

isEmpty

public static boolean isEmpty(ClusteringComparator comparator,
                              ClusteringBound<?> start,
                              ClusteringBound<?> end)

Return whether the slice formed by the two provided bound is empty or not.

Parameters:

comparator - the comparator to compare the bounds.

start - the start for the slice to consider. This must be a start bound.

end - the end for the slice to consider. This must be an end bound.

Returns:

whether the slice formed by start and end is empty or not.

includes

public boolean includes(ClusteringComparator comparator,
                        ClusteringPrefix<?> bound)

Returns whether a given clustering or bound is included in this slice.

Parameters:

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

bound - the bound to test inclusion of.

Returns:

whether bound is within the bounds of this slice.

forPaging

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

Returns a slice for continuing paging from 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:

a new slice that selects results coming after lastReturned, or null if paging the resulting slice selects nothing (i.e. if it originally selects nothing coming after lastReturned).

intersects

public boolean intersects(ClusteringComparator comparator,
                          Slice other)

Whether this slice and the provided slice intersects.

Parameters:

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

other - the other slice to check intersection with.

Returns:

whether this slice intersects other.

toString

public java.lang.String toString(ClusteringComparator comparator)

equals

public boolean equals(java.lang.Object other)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object