mondrian.olap
Class ValidatorImpl

java.lang.Object
  mondrian.olap.ValidatorImpl

All Implemented Interfaces:

Validator

abstract class ValidatorImpl
extends Object
implements Validator

Default implementation of Validator.

Uses a stack to help us guess the type of our parent expression before we've completely resolved our children -- necessary, unfortunately, when figuring out whether the "*" operator denotes multiplication or crossjoin.

Keeps track of which nodes have already been resolved, so we don't try to resolve nodes which have already been resolved. (That would not be wrong, but can cause resolution to be an O(2^N) operation.)

The concrete implementing class needs to implement Validator.getQuery() and defineParameter(Parameter).

Author:

jhyde

Field Summary

protected ArrayStack<QueryPart>

stack

Constructor Summary

protected

ValidatorImpl(FunTable funTable) Creates a ValidatorImpl.

Method Summary

boolean	alwaysResolveFunDef() Whether to resolve function name and arguments to a function definition each time a node is validated, not just the first time.
boolean	canConvert(int ordinal, Exp fromExp, int to, List<Resolver.Conversion> conversions) Returns whether we can convert an argument to a parameter type.
Parameter	createOrLookupParam(boolean definition, String name, Type type, Exp defaultExp, String description) Creates or retrieves the parameter corresponding to a "Parameter" or "ParamRef" function call.
protected abstract void	defineParameter(Parameter param) Defines a parameter.
FunDef	getDef(Exp[] args, String funName, Syntax syntax) Resolves a function call to a particular function.
FunTable	getFunTable() Returns the table of function and operator definitions.
boolean	requiresExpression() Returns whether the current context requires an expression.
(package private) boolean	requiresExpression(UnresolvedFunCall funCall, int k) Returns whether the kth argument to a function call has to be an expression.
Exp	validate(Exp exp, boolean scalar) Validates an expression, and returns the expression it resolves to.
void	validate(Formula formula) Validates a formula.
void	validate(MemberProperty memberProperty) Validates a child member property.
void	validate(ParameterExpr parameterExpr) Validates a usage of a parameter.
void	validate(QueryAxis axis) Validates an axis.

Methods inherited from class java.lang.Object

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

Methods inherited from interface mondrian.olap.Validator

getQuery, getSchemaReader

Field Detail

stack

protected final ArrayStack<QueryPart> stack

Constructor Detail

ValidatorImpl

protected ValidatorImpl(FunTable funTable)

Creates a ValidatorImpl.

Parameters:

funTable - Function table

Pre-condition:

funTable != null

Method Detail

validate

public Exp validate(Exp exp,
                    boolean scalar)

Description copied from interface: Validator

Validates an expression, and returns the expression it resolves to.

Specified by:

validate in interface Validator

Parameters:

exp - Expression to validate

scalar - Whether the context requires that the expression is evaluated to a value, as opposed to a tuple

validate

public void validate(ParameterExpr parameterExpr)

Description copied from interface: Validator

Validates a usage of a parameter.

It must resolve to the same object (although sub-objects may change).

Specified by:

validate in interface Validator

validate

public void validate(MemberProperty memberProperty)

Description copied from interface: Validator

Validates a child member property.

It must resolve to the same object (although sub-objects may change).

Specified by:

validate in interface Validator

validate

public void validate(QueryAxis axis)

Description copied from interface: Validator

Validates an axis. It must resolve to the same object (although sub-objects may change).

Specified by:

validate in interface Validator

validate

public void validate(Formula formula)

Description copied from interface: Validator

Validates a formula. It must resolve to the same object (although sub-objects may change).

Specified by:

validate in interface Validator

getDef

public FunDef getDef(Exp[] args,
                     String funName,
                     Syntax syntax)

Description copied from interface: Validator

Resolves a function call to a particular function. If the function is overloaded, returns as precise a match to the argument types as possible.

Specified by:

getDef in interface Validator

alwaysResolveFunDef

public boolean alwaysResolveFunDef()

Description copied from interface: Validator

Whether to resolve function name and arguments to a function definition each time a node is validated, not just the first time.

Default implementation returns false.

Specified by:

alwaysResolveFunDef in interface Validator

Returns:

whether to resolve function each time

canConvert

public boolean canConvert(int ordinal,
                          Exp fromExp,
                          int to,
                          List<Resolver.Conversion> conversions)

Description copied from interface: Validator

Returns whether we can convert an argument to a parameter type.

Specified by:

canConvert in interface Validator

Parameters:

ordinal - argument ordinal

fromExp - argument type

to - parameter type

conversions - List of conversions performed; method adds an element for each non-trivial conversion (for example, converting a member to a level).

Returns:

Whether we can convert an argument to a parameter type

requiresExpression

public boolean requiresExpression()

Description copied from interface: Validator

Returns whether the current context requires an expression.

Specified by:

requiresExpression in interface Validator

requiresExpression

boolean requiresExpression(UnresolvedFunCall funCall,
                           int k)

Returns whether the kth argument to a function call has to be an expression.

getFunTable

public FunTable getFunTable()

Description copied from interface: Validator

Returns the table of function and operator definitions.

Specified by:

getFunTable in interface Validator

createOrLookupParam

public Parameter createOrLookupParam(boolean definition,
                                     String name,
                                     Type type,
                                     Exp defaultExp,
                                     String description)

Description copied from interface: Validator

Creates or retrieves the parameter corresponding to a "Parameter" or "ParamRef" function call.

Specified by:

createOrLookupParam in interface Validator

defineParameter

protected abstract void defineParameter(Parameter param)

Defines a parameter.

Parameters:

param - Parameter