org.apache.calcite.linq4j.tree

Class ConstantUntypedNull

java.lang.Object

org.apache.calcite.linq4j.tree.AbstractNode

org.apache.calcite.linq4j.tree.Expression

org.apache.calcite.linq4j.tree.ConstantExpression

org.apache.calcite.linq4j.tree.ConstantUntypedNull

All Implemented Interfaces:

Node

public class ConstantUntypedNull
extends ConstantExpression

Represents a constant null of unknown type Java allows type inference for such nulls, thus "null" cannot always be replaced to (Object)null and vise versa. ConstantExpression(null, Object.class) is not equal to ConstantUntypedNull However, optimizers might treat all the nulls equal (e.g. in case of comparison).

Field Summary

Fields

Modifier and Type	Field and Description
static ConstantExpression	INSTANCE

Fields inherited from class org.apache.calcite.linq4j.tree.ConstantExpression

value

Fields inherited from class org.apache.calcite.linq4j.tree.AbstractNode

nodeType, type

Constructor Summary

Constructors

Modifier	Constructor and Description
private	ConstantUntypedNull()

Method Summary

Methods

Modifier and Type	Method and Description
(package private) void	accept(ExpressionWriter writer, int lprec, int rprec)
boolean	equals(Object o)
int	hashCode()

Methods inherited from class org.apache.calcite.linq4j.tree.ConstantExpression

accept, evaluate

Methods inherited from class org.apache.calcite.linq4j.tree.Expression

canReduce

Methods inherited from class org.apache.calcite.linq4j.tree.AbstractNode

accept, accept0, getNodeType, getType, toString

Methods inherited from class java.lang.Object

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

Field Detail

INSTANCE

public static final ConstantExpression INSTANCE

Constructor Detail

ConstantUntypedNull

private ConstantUntypedNull()

Method Detail

accept

void accept(ExpressionWriter writer,
          int lprec,
          int rprec)

Overrides:

accept in class ConstantExpression

equals

public boolean equals(Object o)

Overrides:

equals in class ConstantExpression

hashCode

public int hashCode()

Overrides:

hashCode in class ConstantExpression