mondrian.calc.impl
Class AbstractCalc

java.lang.Object
  mondrian.calc.impl.AbstractCalc

All Implemented Interfaces:

Calc

Direct Known Subclasses:

AbstractBooleanCalc, AbstractDateTimeCalc, AbstractDimensionCalc, AbstractDoubleCalc, AbstractHierarchyCalc, AbstractIntegerCalc, AbstractIterCalc, AbstractLevelCalc, AbstractListCalc, AbstractMemberCalc, AbstractMemberListCalc, AbstractStringCalc, AbstractTupleCalc, GenericCalc

public abstract class AbstractCalc
extends Object
implements Calc

Abstract implementation of the Calc interface.

Since:

Sep 27, 2005

Author:

jhyde

Field Summary

protected Exp	exp
protected Type	type

Constructor Summary

protected

AbstractCalc(Exp exp)

Method Summary

void	accept(CalcWriter calcWriter) Prints this expression, by accepting a visiting CalcWriter.
static boolean	anyDepends(Calc[] calcs, Dimension dimension) Returns true if one of the calcs depends on the given dimension.
static boolean	anyDependsButFirst(Calc[] calcs, Dimension dimension) Returns true if calc[0] depends on dimension, else false if calc[0] returns dimension, else true if any of the other calcs depend on dimension.
static boolean	butDepends(Calc[] calcs, Dimension dimension) Returns true if any of the calcs depend on dimension, else false if any of the calcs return dimension, else true.
boolean	dependsOn(Dimension dimension) Returns whether this expression depends upon a given dimension.
List<Object>	getArguments() Returns any other arguments to this calc.
abstract Calc[]	getCalcs() Returns this expression's child expressions.
protected String	getName() Returns the name of this expression type, used when serializing an expression to a string.
ResultStyle	getResultStyle() Returns style in which the result of evaluating this expression is returned.
Type	getType() Returns the type of this expression.
static Evaluator	simplifyEvaluator(Calc calc, Evaluator evaluator) Returns a simplified evalator whose context is the same for every dimension which an expression depends on, and the default member for every dimension which it does not depend on.

Methods inherited from class java.lang.Object

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

Methods inherited from interface mondrian.calc.Calc

evaluate

Field Detail

type

protected final Type type

exp

protected final Exp exp

Constructor Detail

AbstractCalc

protected AbstractCalc(Exp exp)

Method Detail

getType

public Type getType()

Description copied from interface: Calc

Returns the type of this expression.

Specified by:

getType in interface Calc

accept

public void accept(CalcWriter calcWriter)

Description copied from interface: Calc

Prints this expression, by accepting a visiting CalcWriter.

Specified by:

accept in interface Calc

Parameters:

calcWriter - Writer

getName

protected String getName()

Returns the name of this expression type, used when serializing an expression to a string.

The default implementation tries to extract a name from a function call, if any, then prints the last part of the class name.

getCalcs

public abstract Calc[] getCalcs()

Returns this expression's child expressions.

dependsOn

public boolean dependsOn(Dimension dimension)

Description copied from interface: Calc

Returns whether this expression depends upon a given dimension.

If it does not depend on the dimension, then re-evaluating the expression with a different member of this context must produce the same answer.

Some examples:

• The expression

  [Measures].[Unit Sales]

  depends on all dimensions except [Measures].
• The boolean expression

  ([Measures].[Unit Sales], [Time].[1997]) > 1000

  depends on all dimensions except [Measures] and [Time].
• The list expression

  Filter([Store].[USA].Children, [Measures].[Unit Sales] < 50)

  depends upon all dimensions except [Store] and [Measures]. How so? Normally the scalar expression would depend upon all dimensions except [Measures], but the Filter function sets the [Store] context before evaluating the scalar expression, so it is not inherited from the surrounding context.

Specified by:

dependsOn in interface Calc

Parameters:

dimension - Dimension

Returns:

Whether this expression's result depends upon the current member of the dimension

anyDepends

public static boolean anyDepends(Calc[] calcs,
                                 Dimension dimension)

Returns true if one of the calcs depends on the given dimension.

anyDependsButFirst

public static boolean anyDependsButFirst(Calc[] calcs,
                                         Dimension dimension)

Returns true if calc[0] depends on dimension, else false if calc[0] returns dimension, else true if any of the other calcs depend on dimension.

Typical application: Aggregate({Set}, {Value Expression}) depends upon everything {Value Expression} depends upon, except the dimensions of {Set}.

butDepends

public static boolean butDepends(Calc[] calcs,
                                 Dimension dimension)

Returns true if any of the calcs depend on dimension, else false if any of the calcs return dimension, else true.

getArguments

public List<Object> getArguments()

Returns any other arguments to this calc. The default implementation returns the empty list.

simplifyEvaluator

public static Evaluator simplifyEvaluator(Calc calc,
                                          Evaluator evaluator)

Returns a simplified evalator whose context is the same for every dimension which an expression depends on, and the default member for every dimension which it does not depend on.

The default member is often the 'all' member, so this evaluator is usually the most efficient context in which to evaluate the expression.

Parameters:

calc -

evaluator -

getResultStyle

public ResultStyle getResultStyle()

Description copied from interface: Calc

Returns style in which the result of evaluating this expression is returned.

One application of this method is for the compiler to figure out whether the compiled expression is returning a mutable list. If a mutable list is required, the compiler can create a mutable copy.

Specified by:

getResultStyle in interface Calc

See Also:

ExpCompiler.compileList(mondrian.olap.Exp, boolean)