001 /*
002 // $Id: //open/mondrian/src/main/mondrian/olap/fun/ParallelPeriodFunDef.java#5 $
003 // This software is subject to the terms of the Common Public License
004 // Agreement, available at the following URL:
005 // http://www.opensource.org/licenses/cpl.html.
006 // Copyright (C) 2006-2008 Julian Hyde
007 // All Rights Reserved.
008 // You must accept the terms of that agreement to use this software.
009 */
010 package mondrian.olap.fun;
011
012 import mondrian.olap.*;
013 import mondrian.olap.type.Type;
014 import mondrian.olap.type.MemberType;
015 import mondrian.calc.*;
016 import mondrian.calc.impl.DimensionCurrentMemberCalc;
017 import mondrian.calc.impl.ConstantCalc;
018 import mondrian.calc.impl.AbstractMemberCalc;
019 import mondrian.mdx.ResolvedFunCall;
020 import mondrian.resource.MondrianResource;
021
022 /**
023 * Definition of the <code>ParallelPeriod</code> MDX function.
024 *
025 * @author jhyde
026 * @version $Id: //open/mondrian/src/main/mondrian/olap/fun/ParallelPeriodFunDef.java#5 $
027 * @since Mar 23, 2006
028 */
029 class ParallelPeriodFunDef extends FunDefBase {
030 static final ReflectiveMultiResolver Resolver = new ReflectiveMultiResolver(
031 "ParallelPeriod",
032 "ParallelPeriod([<Level>[, <Numeric Expression>[, <Member>]]])",
033 "Returns a member from a prior period in the same relative position as a specified member.",
034 new String[] {"fm", "fml", "fmln", "fmlnm"},
035 ParallelPeriodFunDef.class);
036
037 public ParallelPeriodFunDef(FunDef dummyFunDef) {
038 super(dummyFunDef);
039 }
040
041 public Type getResultType(Validator validator, Exp[] args) {
042 if (args.length == 0) {
043 // With no args, the default implementation cannot
044 // guess the hierarchy, so we supply the Time
045 // dimension.
046 Dimension defaultTimeDimension =
047 validator.getQuery().getCube().getTimeDimension();
048 if (defaultTimeDimension == null) {
049 throw MondrianResource.instance().
050 NoTimeDimensionInCube.ex(getName());
051 }
052 Hierarchy hierarchy = defaultTimeDimension.getHierarchy();
053 return MemberType.forHierarchy(hierarchy);
054 }
055 return super.getResultType(validator, args);
056 }
057
058 public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
059 // Member defaults to [Time].currentmember
060 Exp[] args = call.getArgs();
061 final MemberCalc memberCalc;
062 switch (args.length) {
063 case 3:
064 memberCalc = compiler.compileMember(args[2]);
065 break;
066 case 1:
067 final Dimension dimension =
068 args[0].getType().getHierarchy().getDimension();
069 memberCalc = new DimensionCurrentMemberCalc(dimension);
070 break;
071 default:
072 final Dimension timeDimension =
073 compiler.getEvaluator().getCube()
074 .getTimeDimension();
075 if (timeDimension == null) {
076 throw MondrianResource.instance().
077 NoTimeDimensionInCube.ex(getName());
078 }
079 memberCalc = new DimensionCurrentMemberCalc(
080 timeDimension);
081 break;
082 }
083
084 // Numeric Expression defaults to 1.
085 final IntegerCalc lagValueCalc = (args.length >= 2) ?
086 compiler.compileInteger(args[1]) :
087 ConstantCalc.constantInteger(1);
088
089 // If level is not specified, we compute it from
090 // member at runtime.
091 final LevelCalc ancestorLevelCalc =
092 args.length >= 1 ?
093 compiler.compileLevel(args[0]) :
094 null;
095
096 return new AbstractMemberCalc(call, new Calc[] {memberCalc, lagValueCalc, ancestorLevelCalc}) {
097 public Member evaluateMember(Evaluator evaluator) {
098 Member member = memberCalc.evaluateMember(
099 evaluator);
100 int lagValue = lagValueCalc.evaluateInteger(
101 evaluator);
102 Level ancestorLevel;
103 if (ancestorLevelCalc != null) {
104 ancestorLevel = ancestorLevelCalc
105 .evaluateLevel(evaluator);
106 } else {
107 Member parent = member.getParentMember();
108 if (parent == null) {
109 // This is a root member,
110 // so there is no parallelperiod.
111 return member.getHierarchy()
112 .getNullMember();
113 }
114 ancestorLevel = parent.getLevel();
115 }
116 return parallelPeriod(member, ancestorLevel,
117 evaluator, lagValue);
118 }
119 };
120 }
121
122 Member parallelPeriod(
123 Member member,
124 Level ancestorLevel,
125 Evaluator evaluator,
126 int lagValue) {
127 // Now do some error checking.
128 // The ancestorLevel and the member must be from the
129 // same hierarchy.
130 if (member.getHierarchy() != ancestorLevel.getHierarchy()) {
131 MondrianResource.instance().FunctionMbrAndLevelHierarchyMismatch.ex(
132 "ParallelPeriod",
133 ancestorLevel.getHierarchy().getUniqueName(),
134 member.getHierarchy().getUniqueName());
135 }
136
137 if (lagValue == Integer.MIN_VALUE) {
138 // bump up lagValue by one
139 // otherwise -lagValue(used in the getleadMember call below)is out of range
140 // because Integer.MAX_VALUE == -(Integer.MIN_VALUE + 1)
141 lagValue += 1;
142 }
143
144 int distance = member.getLevel().getDepth() -
145 ancestorLevel.getDepth();
146 Member ancestor = FunUtil.ancestor(
147 evaluator, member, distance, ancestorLevel);
148 Member inLaw = evaluator.getSchemaReader()
149 .getLeadMember(ancestor, -lagValue);
150 return FunUtil.cousin(
151 evaluator.getSchemaReader(), member, inLaw);
152 }
153 }
154
155 // End ParallelPeriodFunDef.java