Package org.apache.calcite.util.mapping

Class Mappings.IdentityMapping

java.lang.Object

org.apache.calcite.util.mapping.Mappings.AbstractMapping

org.apache.calcite.util.mapping.Mappings.IdentityMapping

All Implemented Interfaces:

Iterable<IntPair>, Mapping, Mappings.CoreMapping, Mappings.FunctionMapping, Mappings.SourceMapping, Mappings.TargetMapping

Enclosing class:

Mappings

public static class Mappings.IdentityMapping
extends Mappings.AbstractMapping
implements Mappings.FunctionMapping, Mappings.TargetMapping, Mappings.SourceMapping

The identity mapping, of a given size, or infinite.

Constructor Summary

Constructors

Constructor	Description
IdentityMapping(int size)	Creates an identity mapping.

Method Summary

Modifier and Type	Method	Description
void	clear()	Removes all elements in the mapping.
MappingType	getMappingType()	Returns the mapping type.
int	getSource(int target)	Returns the source that a target maps to.
int	getSourceCount()	Returns the number of sources.
int	getSourceOpt(int target)	Returns the source that a target maps to, or -1 if it is not mapped.
int	getTarget(int source)	Returns the target that a source maps to.
int	getTargetCount()	Returns the number of targets.
int	getTargetOpt(int source)	Returns the target that a source maps to, or -1 if it is not mapped.
Mapping	inverse()
boolean	isIdentity()	Returns whether this mapping is the identity.
Iterator<IntPair>	iterator()	Returns an iterator over the elements in this mapping.
void	set(int source, int target)
int	size()	Returns the number of elements in the mapping.

Methods inherited from class org.apache.calcite.util.mapping.Mappings.AbstractMapping

toString

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Details

IdentityMapping

public IdentityMapping(int size)

Creates an identity mapping.

Parameters:

size - Size, or -1 if infinite.

Method Details

clear

public void clear()

Description copied from interface: Mapping

Removes all elements in the mapping.

Specified by:

clear in interface Mapping

size

public int size()

Description copied from interface: Mappings.CoreMapping

Returns the number of elements in the mapping.

Specified by:

size in interface Mapping

Specified by:

size in interface Mappings.CoreMapping

inverse

public Mapping inverse()

Specified by:

inverse in interface Mappings.SourceMapping

Specified by:

inverse in interface Mappings.TargetMapping

isIdentity

public boolean isIdentity()

Description copied from interface: Mapping

Returns whether this mapping is the identity.

Specified by:

isIdentity in interface Mapping

Specified by:

isIdentity in interface Mappings.SourceMapping

Overrides:

isIdentity in class Mappings.AbstractMapping

set

public void set(int source,
 int target)

Specified by:

set in interface Mappings.TargetMapping

Overrides:

set in class Mappings.AbstractMapping

getMappingType

public MappingType getMappingType()

Description copied from interface: Mappings.CoreMapping

Returns the mapping type.

Specified by:

getMappingType in interface Mapping

Specified by:

getMappingType in interface Mappings.CoreMapping

Specified by:

getMappingType in interface Mappings.FunctionMapping

Specified by:

getMappingType in interface Mappings.SourceMapping

Returns:

Mapping type

getSourceCount

public int getSourceCount()

Description copied from interface: Mapping

Returns the number of sources. Valid sources will be in the range 0 .. sourceCount.

Specified by:

getSourceCount in interface Mapping

Specified by:

getSourceCount in interface Mappings.FunctionMapping

Specified by:

getSourceCount in interface Mappings.SourceMapping

Specified by:

getSourceCount in interface Mappings.TargetMapping

Overrides:

getSourceCount in class Mappings.AbstractMapping

getTargetCount

public int getTargetCount()

Description copied from interface: Mapping

Returns the number of targets. Valid targets will be in the range 0 .. targetCount.

Specified by:

getTargetCount in interface Mapping

Specified by:

getTargetCount in interface Mappings.SourceMapping

Specified by:

getTargetCount in interface Mappings.TargetMapping

Overrides:

getTargetCount in class Mappings.AbstractMapping

getTarget

public int getTarget(int source)

Returns the target that a source maps to.

Specified by:

getTarget in interface Mappings.FunctionMapping

Specified by:

getTarget in interface Mappings.TargetMapping

Overrides:

getTarget in class Mappings.AbstractMapping

Parameters:

source - source

Returns:

target

getTargetOpt

public int getTargetOpt(int source)

Returns the target that a source maps to, or -1 if it is not mapped.

Specified by:

getTargetOpt in interface Mappings.FunctionMapping

Specified by:

getTargetOpt in interface Mappings.SourceMapping

Specified by:

getTargetOpt in interface Mappings.TargetMapping

Overrides:

getTargetOpt in class Mappings.AbstractMapping

Parameters:

source - source

Returns:

target

getSource

public int getSource(int target)

Returns the source that a target maps to.

Specified by:

getSource in interface Mappings.SourceMapping

Overrides:

getSource in class Mappings.AbstractMapping

Parameters:

target - target

Returns:

source

getSourceOpt

public int getSourceOpt(int target)

Returns the source that a target maps to, or -1 if it is not mapped.

Specified by:

getSourceOpt in interface Mappings.SourceMapping

Specified by:

getSourceOpt in interface Mappings.TargetMapping

Overrides:

getSourceOpt in class Mappings.AbstractMapping

Parameters:

target - target

Returns:

source

iterator

public Iterator<IntPair> iterator()

Description copied from interface: Mapping

Returns an iterator over the elements in this mapping.

This method is optional; implementations may throw UnsupportedOperationException.

Specified by:

iterator in interface Iterable<IntPair>

Specified by:

iterator in interface Mapping