/*
// $Id: //open/mondrian-release/3.2/src/main/mondrian/olap/fun/LastPeriodsFunDef.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.SetType;
import mondrian.olap.type.MemberType;
import mondrian.olap.type.TypeUtil;
import mondrian.resource.MondrianResource;
import mondrian.calc.Calc;
import mondrian.calc.ExpCompiler;
import mondrian.calc.MemberCalc;
import mondrian.calc.IntegerCalc;
import mondrian.calc.impl.AbstractListCalc;
import mondrian.mdx.ResolvedFunCall;
import mondrian.rolap.RolapCube;
import mondrian.rolap.RolapHierarchy;
import java.util.List;
import java.util.Collections;
import java.util.ArrayList;
/**
* Definition of the <code>LastPeriods</code> MDX function.
*
* @author jhyde
* @version $Id: //open/mondrian-release/3.2/src/main/mondrian/olap/fun/LastPeriodsFunDef.java#1 $
* @since Mar 23, 2006
*/
class LastPeriodsFunDef extends FunDefBase {
static final ReflectiveMultiResolver Resolver = new ReflectiveMultiResolver(
"LastPeriods",
"LastPeriods(<Index> [, <Member>])",
"Returns a set of members prior to and including a specified member.",
new String[] {"fxn", "fxnm"},
LastPeriodsFunDef.class);
public LastPeriodsFunDef(FunDef dummyFunDef) {
super(dummyFunDef);
}
public Type getResultType(Validator validator, Exp[] args) {
if (args.length == 1) {
// If Member is not specified,
// it is Time.CurrentMember.
RolapHierarchy defaultTimeHierarchy =
((RolapCube) validator.getQuery().getCube()).getTimeHierarchy(
getName());
return new SetType(MemberType.forHierarchy(defaultTimeHierarchy));
} else {
Type type = args[1].getType();
Type memberType =
TypeUtil.toMemberOrTupleType(type);
return new SetType(memberType);
}
}
public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
// Member defaults to [Time].currentmember
Exp[] args = call.getArgs();
final MemberCalc memberCalc;
if (args.length == 1) {
final RolapHierarchy timeHierarchy =
((RolapCube) compiler.getEvaluator().getCube())
.getTimeHierarchy(getName());
memberCalc =
new HierarchyCurrentMemberFunDef.FixedCalcImpl(
call, timeHierarchy);
} else {
memberCalc = compiler.compileMember(args[1]);
}
// Numeric Expression.
final IntegerCalc indexValueCalc =
compiler.compileInteger(args[0]);
return new AbstractListCalc(
call, new Calc[] {memberCalc, indexValueCalc})
{
public List evaluateList(Evaluator evaluator) {
Member member = memberCalc.evaluateMember(evaluator);
int indexValue = indexValueCalc.evaluateInteger(evaluator);
return lastPeriods(member, evaluator, indexValue);
}
};
}
/**
* If Index is positive, returns the set of Index
* members ending with Member and starting with the
* member lagging Index - 1 from Member.
*
* <p>If Index is negative, returns the set of (- Index)
* members starting with Member and ending with the
* member leading (- Index - 1) from Member.
*
* <p>If Index is zero, the empty set is returned.
*/
List<Member> lastPeriods(
Member member,
Evaluator evaluator,
int indexValue)
{
// empty set
if ((indexValue == 0) || member.isNull()) {
return Collections.emptyList();
}
List<Member> list = new ArrayList<Member>();
// set with just member
if ((indexValue == 1) || (indexValue == -1)) {
list.add(member);
return list;
}
// When null is found, getting the first/last
// member at a given level is not particularly
// fast.
Member startMember;
Member endMember;
if (indexValue > 0) {
startMember = evaluator.getSchemaReader()
.getLeadMember(member, - (indexValue - 1));
endMember = member;
if (startMember.isNull()) {
List<Member> members = evaluator.getSchemaReader()
.getLevelMembers(member.getLevel(), false);
startMember = members.get(0);
}
} else {
startMember = member;
endMember = evaluator.getSchemaReader()
.getLeadMember(member, -(indexValue + 1));
if (endMember.isNull()) {
List<Member> members = evaluator.getSchemaReader()
.getLevelMembers(member.getLevel(), false);
endMember = members.get(members.size() - 1);
}
}
evaluator.getSchemaReader().getMemberRange(
member.getLevel(),
startMember,
endMember,
list);
return list;
}
}
// End LastPeriodsFunDef.java