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1
10 package mondrian.olap.fun;
11
12 import mondrian.olap.*;
13 import mondrian.calc.Calc;
14 import mondrian.calc.ExpCompiler;
15 import mondrian.calc.BooleanCalc;
16 import mondrian.calc.impl.ConstantCalc;
17 import mondrian.calc.impl.AbstractCalc;
18 import mondrian.mdx.ResolvedFunCall;
19
20 import java.util.List  ;
21 import java.util.ArrayList ;
22
23
39 class CaseTestFunDef extends FunDefBase {
40 static final ResolverImpl Resolver = new ResolverImpl();
41
42 public CaseTestFunDef(FunDef dummyFunDef) {
43 super(dummyFunDef);
44 }
45
46 public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
47 final Exp[] args = call.getArgs();
48 final BooleanCalc[] conditionCalcs =
49 new BooleanCalc[args.length / 2];
50 final Calc[] exprCalcs =
51 new Calc[args.length / 2];
52 final List <Calc> calcList = new ArrayList <Calc>();
53 for (int i = 0, j = 0; i < exprCalcs.length; i++) {
54 conditionCalcs[i] =
55 compiler.compileBoolean(args[j++]);
56 calcList.add(conditionCalcs[i]);
57 exprCalcs[i] =
58 compiler.compileScalar(args[j++], true);
59 calcList.add(exprCalcs[i]);
60 }
61 final Calc defaultCalc =
62 args.length % 2 == 1 ?
63 compiler.compileScalar(args[args.length - 1], true) :
64 ConstantCalc.constantNull(call.getType());
65 calcList.add(defaultCalc);
66 final Calc[] calcs = calcList.toArray(new Calc[calcList.size()]);
67
68 return new AbstractCalc(call) {
69 public Object evaluate(Evaluator evaluator) {
70 for (int i = 0; i < conditionCalcs.length; i++) {
71 if (conditionCalcs[i].evaluateBoolean(evaluator)) {
72 return exprCalcs[i].evaluate(evaluator);
73 }
74 }
75 return defaultCalc.evaluate(evaluator);
76 }
77
78 public Calc[] getCalcs() {
79 return calcs;
80 }
81 };
82 }
83
84 private static class ResolverImpl extends ResolverBase {
85 public ResolverImpl() {
86 super(
87 "_CaseTest",
88 "Case When <Logical Expression> Then <Expression> [...] [Else <Expression>] End",
89 "Evaluates various conditions, and returns the corresponding expression for the first which evaluates to true.",
90 Syntax.Case);
91 }
92
93 public FunDef resolve(
94 Exp[] args, Validator validator, int[] conversionCount) {
95 if (args.length < 1) {
96 return null;
97 }
98 int j = 0;
99 int clauseCount = args.length / 2;
100 int mismatchingArgs = 0;
101 int returnType = args[1].getCategory();
102 for (int i = 0; i < clauseCount; i++) {
103 if (!validator.canConvert(args[j++], Category.Logical, conversionCount)) {
104 mismatchingArgs++;
105 }
106 if (!validator.canConvert(args[j++], returnType, conversionCount)) {
107 mismatchingArgs++;
108 }
109 }
110 if (j < args.length) {
111 if (!validator.canConvert(args[j++], returnType, conversionCount)) {
112 mismatchingArgs++;
113 }
114 }
115 Util.assertTrue(j == args.length);
116 if (mismatchingArgs != 0) {
117 return null;
118 }
119 FunDef dummy = createDummyFunDef(this, returnType, args);
120 return new CaseTestFunDef(dummy);
121 }
122
123 public boolean requiresExpression(int k) {
124 return true;
125 }
126 }
127 }
128
129 |
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