/*
// $Id: //open/mondrian-release/3.2/src/main/mondrian/olap/fun/ParallelPeriodFunDef.java#1 $
// This software is subject to the terms of the Eclipse Public License v1.0
// Agreement, available at the following URL:
// http://www.eclipse.org/legal/epl-v10.html.
// Copyright (C) 2006-2009 Julian Hyde
// All Rights Reserved.
// You must accept the terms of that agreement to use this software.
*/
package mondrian.olap.fun;
import mondrian.olap.*;
import mondrian.olap.type.Type;
import mondrian.olap.type.MemberType;
import mondrian.calc.*;
import mondrian.calc.impl.ConstantCalc;
import mondrian.calc.impl.AbstractMemberCalc;
import mondrian.mdx.ResolvedFunCall;
import mondrian.resource.MondrianResource;
import mondrian.rolap.RolapCube;
import mondrian.rolap.RolapHierarchy;
/**
* Definition of the <code>ParallelPeriod</code> MDX function.
*
* @author jhyde
* @version $Id: //open/mondrian-release/3.2/src/main/mondrian/olap/fun/ParallelPeriodFunDef.java#1 $
* @since Mar 23, 2006
*/
class ParallelPeriodFunDef extends FunDefBase {
static final ReflectiveMultiResolver Resolver =
new ReflectiveMultiResolver(
"ParallelPeriod",
"ParallelPeriod([<Level>[, <Numeric Expression>[, <Member>]]])",
"Returns a member from a prior period in the same relative position as a specified member.",
new String[] {"fm", "fml", "fmln", "fmlnm"},
ParallelPeriodFunDef.class);
public ParallelPeriodFunDef(FunDef dummyFunDef) {
super(dummyFunDef);
}
public Type getResultType(Validator validator, Exp[] args) {
if (args.length == 0) {
// With no args, the default implementation cannot
// guess the hierarchy, so we supply the Time
// dimension.
RolapHierarchy defaultTimeHierarchy =
((RolapCube) validator.getQuery().getCube()).getTimeHierarchy(
getName());
return MemberType.forHierarchy(defaultTimeHierarchy);
}
return super.getResultType(validator, args);
}
public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
// Member defaults to [Time].currentmember
Exp[] args = call.getArgs();
// Numeric Expression defaults to 1.
final IntegerCalc lagValueCalc =
(args.length >= 2)
? compiler.compileInteger(args[1])
: ConstantCalc.constantInteger(1);
// If level is not specified, we compute it from
// member at runtime.
final LevelCalc ancestorLevelCalc =
args.length >= 1
? compiler.compileLevel(args[0])
: null;
final MemberCalc memberCalc;
switch (args.length) {
case 3:
memberCalc = compiler.compileMember(args[2]);
break;
case 1:
final Hierarchy hierarchy = args[0].getType().getHierarchy();
if (hierarchy != null) {
// For some functions, such as Levels(<string expression>),
// the dimension cannot be determined at compile time.
memberCalc =
new HierarchyCurrentMemberFunDef.FixedCalcImpl(
call, hierarchy);
} else {
memberCalc = null;
}
break;
default:
final RolapHierarchy timeHierarchy =
((RolapCube) compiler.getEvaluator().getCube())
.getTimeHierarchy(getName());
memberCalc =
new HierarchyCurrentMemberFunDef.FixedCalcImpl(
call, timeHierarchy);
break;
}
return new AbstractMemberCalc(
call,
new Calc[] {memberCalc, lagValueCalc, ancestorLevelCalc})
{
public Member evaluateMember(Evaluator evaluator) {
Member member;
int lagValue = lagValueCalc.evaluateInteger(
evaluator);
Level ancestorLevel;
if (ancestorLevelCalc != null) {
ancestorLevel = ancestorLevelCalc.evaluateLevel(evaluator);
if (memberCalc == null) {
member =
evaluator.getContext(ancestorLevel.getHierarchy());
} else {
member = memberCalc.evaluateMember(evaluator);
}
} else {
member = memberCalc.evaluateMember(evaluator);
Member parent = member.getParentMember();
if (parent == null) {
// This is a root member,
// so there is no parallelperiod.
return member.getHierarchy().getNullMember();
}
ancestorLevel = parent.getLevel();
}
return parallelPeriod(
member, ancestorLevel, evaluator, lagValue);
}
};
}
Member parallelPeriod(
Member member,
Level ancestorLevel,
Evaluator evaluator,
int lagValue)
{
// Now do some error checking.
// The ancestorLevel and the member must be from the
// same hierarchy.
if (member.getHierarchy() != ancestorLevel.getHierarchy()) {
MondrianResource.instance().FunctionMbrAndLevelHierarchyMismatch.ex(
"ParallelPeriod",
ancestorLevel.getHierarchy().getUniqueName(),
member.getHierarchy().getUniqueName());
}
if (lagValue == Integer.MIN_VALUE) {
// Bump up lagValue by one; otherwise -lagValue (used in
// the getleadMember call below) is out of range because
// Integer.MAX_VALUE == -(Integer.MIN_VALUE + 1)
lagValue += 1;
}
int distance =
member.getLevel().getDepth()
- ancestorLevel.getDepth();
Member ancestor = FunUtil.ancestor(
evaluator, member, distance, ancestorLevel);
Member inLaw = evaluator.getSchemaReader()
.getLeadMember(ancestor, -lagValue);
return FunUtil.cousin(
evaluator.getSchemaReader(), member, inLaw);
}
}
// End ParallelPeriodFunDef.java