Package org.apache.calcite.rel.mutable

Class MutableRel

java.lang.Object

org.apache.calcite.rel.mutable.MutableRel

Direct Known Subclasses:

Holder, MutableAggregate, MutableCalc, MutableCollect, MutableCorrelate, MutableExchange, MutableFilter, MutableJoin, MutableMatch, MutableProject, MutableSample, MutableScan, MutableSetOp, MutableSort, MutableTableFunctionScan, MutableTableModify, MutableUncollect, MutableValues, MutableWindow

public abstract class MutableRel
extends Object

Mutable equivalent of RelNode.

Each node has mutable state, and keeps track of its parent and position within parent. It doesn't make sense to canonize MutableRels, otherwise one node could end up with multiple parents. It follows that #hashCode and #equals are less efficient than their RelNode counterparts. But, you don't need to copy a MutableRel in order to change it. For this reason, you should use MutableRel for short-lived operations, and transcribe back to RelNode when you are done.

Field Summary

Fields

Modifier and Type	Field	Description
final RelOptCluster	cluster
protected int	ordinalInParent
protected static final com.google.common.base.Equivalence<List<?>>	PAIRWISE_STRING_EQUIVALENCE	Equivalence that compares Listss by the Object.toString() of their elements.
protected @Nullable MutableRel	parent
final RelDataType	rowType
protected static final com.google.common.base.Equivalence<Object>	STRING_EQUIVALENCE	Equivalence that compares objects by their Object.toString() method.
protected final org.apache.calcite.rel.mutable.MutableRelType	type

Constructor Summary

Constructors

Modifier	Constructor	Description
protected	MutableRel(RelOptCluster cluster, RelDataType rowType, org.apache.calcite.rel.mutable.MutableRelType type)

Method Summary

Modifier and Type	Method	Description
abstract void	childrenAccept(MutableRelVisitor visitor)
abstract MutableRel	clone()
final String	deep()
abstract StringBuilder	digest(StringBuilder buf)
abstract List<MutableRel>	getInputs()
@Nullable MutableRel	getParent()
@Nullable MutableRel	replaceInParent(MutableRel child)	Replaces this MutableRel in its parent with another node at the same position.
abstract void	setInput(int ordinalInParent, MutableRel input)
final String	toString()

Methods inherited from class java.lang.Object

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

Field Details

STRING_EQUIVALENCE

protected static final com.google.common.base.Equivalence<Object> STRING_EQUIVALENCE

Equivalence that compares objects by their Object.toString() method.

PAIRWISE_STRING_EQUIVALENCE

protected static final com.google.common.base.Equivalence<List<?>> PAIRWISE_STRING_EQUIVALENCE

Equivalence that compares Listss by the Object.toString() of their elements.

cluster

public final RelOptCluster cluster

rowType

public final RelDataType rowType

type

protected final org.apache.calcite.rel.mutable.MutableRelType type

parent

protected @Nullable MutableRel parent

ordinalInParent

protected int ordinalInParent

Constructor Details

MutableRel

protected MutableRel(RelOptCluster cluster,
 RelDataType rowType,
 org.apache.calcite.rel.mutable.MutableRelType type)

Method Details

getParent

public @Nullable MutableRel getParent()

setInput

public abstract void setInput(int ordinalInParent,
 MutableRel input)

getInputs

public abstract List<MutableRel> getInputs()

clone

public abstract MutableRel clone()

Overrides:

clone in class Object

childrenAccept

public abstract void childrenAccept(MutableRelVisitor visitor)

replaceInParent

public @Nullable MutableRel replaceInParent(MutableRel child)

Replaces this MutableRel in its parent with another node at the same position.

Before the method, child must be an orphan (have null parent) and after this method, this MutableRel is an orphan.

Returns:

The parent

digest

public abstract StringBuilder digest(StringBuilder buf)

deep

public final String deep()

toString

public final String toString()

Overrides:

toString in class Object