org.eigenbase.rex
Class RexChecker

java.lang.Object
  org.eigenbase.rex.RexVisitorImpl<Boolean>
      org.eigenbase.rex.RexChecker

All Implemented Interfaces:

RexVisitor<Boolean>

Direct Known Subclasses:

RexProgram.Checker

public class RexChecker
extends RexVisitorImpl<Boolean>

Visitor which checks the validity of a RexNode expression.

There are two modes of operation:

• Usefail=true to throw an AssertionError as soon as an invalid node is detected:

  RexNode node;
RelDataType rowType;
assert new RexChecker(rowType, true).isValid(node);

  This mode requires that assertions are enabled.
• Use fail=false to test for validity without throwing an error.

  RexNode node;
RelDataType rowType;
RexChecker checker = new RexChecker(rowType, false);
node.accept(checker);
if (!checker.valid) {
...
}


Since:

May 21, 2006

Version:

$Id: //open/dev/farrago/src/org/eigenbase/rex/RexChecker.java#8 $

Author:

jhyde

See Also:

RexNode

Field Summary

protected boolean	fail
protected int	failCount
protected List<RelDataType>	inputTypeList

Fields inherited from class org.eigenbase.rex.RexVisitorImpl

deep

Constructor Summary

RexChecker(List<RelDataType> inputTypeList, boolean fail)
Creates a RexChecker with a given set of input fields.

RexChecker(RelDataType inputRowType, boolean fail)
Creates a RexChecker with a given input row type.

Method Summary

int	getFailureCount() Returns the number of failures encountered.
boolean	isValid(RexNode expr) Returns whether an expression is valid.
Boolean	visitCall(RexCall call)
Boolean	visitFieldAccess(RexFieldAccess fieldAccess)
Boolean	visitInputRef(RexInputRef ref)
Boolean	visitLocalRef(RexLocalRef ref)

Methods inherited from class org.eigenbase.rex.RexVisitorImpl

visitArrayAnd, visitArrayOr, visitCorrelVariable, visitDynamicParam, visitLiteral, visitOver, visitRangeRef

Methods inherited from class java.lang.Object

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

Field Detail

fail

protected final boolean fail

inputTypeList

protected final List<RelDataType> inputTypeList

failCount

protected int failCount

Constructor Detail

RexChecker

public RexChecker(RelDataType inputRowType,
                  boolean fail)

Creates a RexChecker with a given input row type.

If fail is true, the checker will throw an AssertionError if an invalid node is found and assertions are enabled.

Otherwise, each method returns whether its part of the tree is valid.

Parameters:

inputRowType - Input row type

fail - Whether to throw an AssertionError if an invalid node is detected

RexChecker

public RexChecker(List<RelDataType> inputTypeList,
                  boolean fail)

Creates a RexChecker with a given set of input fields.

If fail is true, the checker will throw an AssertionError if an invalid node is found and assertions are enabled.

Otherwise, each method returns whether its part of the tree is valid.

Parameters:

inputTypeList - Input row type

fail - Whether to throw an AssertionError if an invalid node is detected

Method Detail

getFailureCount

public int getFailureCount()

Returns the number of failures encountered.

Returns:

Number of failures

visitInputRef

public Boolean visitInputRef(RexInputRef ref)

Specified by:

visitInputRef in interface RexVisitor<Boolean>

Overrides:

visitInputRef in class RexVisitorImpl<Boolean>

visitLocalRef

public Boolean visitLocalRef(RexLocalRef ref)

Specified by:

visitLocalRef in interface RexVisitor<Boolean>

Overrides:

visitLocalRef in class RexVisitorImpl<Boolean>

visitCall

public Boolean visitCall(RexCall call)

Specified by:

visitCall in interface RexVisitor<Boolean>

Overrides:

visitCall in class RexVisitorImpl<Boolean>

visitFieldAccess

public Boolean visitFieldAccess(RexFieldAccess fieldAccess)

Specified by:

visitFieldAccess in interface RexVisitor<Boolean>

Overrides:

visitFieldAccess in class RexVisitorImpl<Boolean>

isValid

public final boolean isValid(RexNode expr)

Returns whether an expression is valid.