org.eigenbase.oj.util
Class JavaRowExpression

java.lang.Object
  org.eigenbase.rex.RexNode
      org.eigenbase.oj.util.JavaRowExpression

public class JavaRowExpression
extends RexNode

A row expression which is implemented by an underlying Java expression.

This is a leaf node of a RexNode tree, but the Java expression, represented by a Expression object, may be complex.

Since:

Nov 23, 2003

Version:

$Id: //open/dev/farrago/src/org/eigenbase/oj/util/JavaRowExpression.java#14 $

Author:

jhyde

See Also:

JavaRexBuilder

Field Summary

(package private) Environment	env
private Expression	expression
private RelDataType	type

Fields inherited from class org.eigenbase.rex.RexNode

digest, EMPTY_ARRAY

Constructor Summary

JavaRowExpression(Environment env, RelDataType type, Expression expression)

Method Summary

<R> R	accept(RexVisitor<R> visitor) Accepts a visitor, dispatching to the right overloaded visitXxx method.
JavaRowExpression	clone()
Expression	getExpression()
RelDataType	getType()
boolean	isAlwaysTrue() Returns whether this expression always returns true.

Methods inherited from class org.eigenbase.rex.RexNode

getKind, isA, toString

Methods inherited from class java.lang.Object

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

Field Detail

env

final Environment env

type

private final RelDataType type

expression

private final Expression expression

Constructor Detail

JavaRowExpression

public JavaRowExpression(Environment env,
                         RelDataType type,
                         Expression expression)

Method Detail

isAlwaysTrue

public boolean isAlwaysTrue()

Description copied from class: RexNode

Returns whether this expression always returns true. (Such as if this expression is equal to the literal TRUE.)

Overrides:

isAlwaysTrue in class RexNode

accept

public <R> R accept(RexVisitor<R> visitor)

Description copied from class: RexNode

Accepts a visitor, dispatching to the right overloaded visitXxx method.

Also see RexProgram.apply(RexVisitor, RexNode[], RexNode), which applies a visitor to several expressions simultaneously.

Specified by:

accept in class RexNode

getType

public RelDataType getType()

Specified by:

getType in class RexNode

getExpression

public Expression getExpression()

clone

public JavaRowExpression clone()

Specified by:

clone in class RexNode