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10 package mondrian.olap.fun;
11
12 import mondrian.olap.*;
13 import mondrian.olap.type.Type;
14 import mondrian.resource.MondrianResource;
15 import mondrian.calc.Calc;
16 import mondrian.calc.ExpCompiler;
17 import mondrian.calc.impl.GenericCalc;
18 import mondrian.mdx.ResolvedFunCall;
19 import mondrian.olap.fun.FunUtil;
20
21
41 public class CastFunDef extends FunDefBase {
42 static final ResolverBase Resolver = new ResolverImpl();
43
44 private CastFunDef(FunDef dummyFunDef) {
45 super(dummyFunDef);
46 }
47
48 public Calc compileCall(ResolvedFunCall call, ExpCompiler compiler) {
49 final Type targetType = call.getType();
50 final Exp arg = call.getArg(0);
51 final Calc calc = compiler.compileScalar(arg, false);
52 return new GenericCalc(arg) {
53 public Calc[] getCalcs() {
54 return new Calc[] {calc};
55 }
56
57 public Object  evaluate(Evaluator evaluator) {
58 return calc.evaluate(evaluator);
59 }
60
61 public String evaluateString(Evaluator evaluator) {
62 final Object o = evaluate(evaluator);
63 if (o == null) {
64 return null;
65 }
66 return String.valueOf(o);
67 }
68
69 public int evaluateInteger(Evaluator evaluator) {
70 final Object o = evaluate(evaluator);
71 if (o == null) {
72 return FunUtil.IntegerNull;
73 }
74 if (o instanceof String ) {
75 return Integer.parseInt((String ) o);
76 }
77 if (o instanceof Number ) {
78 return ((Number ) o).intValue();
79 }
80 throw cannotConvert(o);
81 }
82
83 public double evaluateDouble(Evaluator evaluator) {
84 final Object o = evaluate(evaluator);
85 if (o == null) {
86 return FunUtil.DoubleNull;
87 }
88 if (o instanceof String ) {
89 return Double.valueOf((String ) o);
90 }
91 if (o instanceof Number ) {
92 return ((Number ) o).doubleValue();
93 }
94 throw cannotConvert(o);
95 }
96
97 public boolean evaluateBoolean(Evaluator evaluator) {
98 final Object o = evaluate(evaluator);
99 if (o == null) {
100 return FunUtil.BooleanNull;
101 }
102 if (o instanceof Boolean ) {
103 return (Boolean ) o;
104 }
105 if (o instanceof String ) {
106 return Boolean.valueOf((String ) o);
107 }
108 throw cannotConvert(o);
109 }
110
111 private RuntimeException cannotConvert(Object o) {
112 return Util.newInternal(
113 "cannot convert value '" + o +
114 "' to targetType '" + targetType +
115 "'");
116 }
117 };
118 }
119
120
123 private static class ResolverImpl extends ResolverBase {
124
125 public ResolverImpl() {
126 super("Cast", "Cast(<Expression> AS <Type>)",
127 "Converts values to another type.", Syntax.Cast);
128 }
129
130 public FunDef resolve(
131 Exp[] args, Validator validator, int[] conversionCount) {
132 if (args.length != 2) {
133 return null;
134 }
135 if (!(args[1] instanceof Literal)) {
136 return null;
137 }
138 Literal literal = (Literal) args[1];
139 String typeName = (String ) literal.getValue();
140 int returnCategory;
141 if (typeName.equalsIgnoreCase("String")) {
142 returnCategory = Category.String;
143 } else if (typeName.equalsIgnoreCase("Numeric")) {
144 returnCategory = Category.Numeric;
145 } else if (typeName.equalsIgnoreCase("Boolean")) {
146 returnCategory = Category.Logical;
147 } else if (typeName.equalsIgnoreCase("Integer")) {
148 returnCategory = Category.Integer;
149 } else {
150 throw MondrianResource.instance().CastInvalidType.ex(typeName);
151 }
152 final FunDef dummyFunDef =
153 createDummyFunDef(this, returnCategory, args);
154 return new CastFunDef(dummyFunDef);
155 }
156 }
157 }
158
159 |
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