public static FieldValue evaluate(
DefineFunction defineFunction, List<FieldValue> values, EvaluationContext context) {
List<ParameterField> parameterFields = defineFunction.getParameterFields();
if (parameterFields.size() < 1) {
throw new InvalidFeatureException(defineFunction);
} // End if
if (parameterFields.size() != values.size()) {
throw new EvaluationException();
}
FunctionEvaluationContext functionContext = new FunctionEvaluationContext(context);
for (int i = 0; i < parameterFields.size(); i++) {
ParameterField parameterField = parameterFields.get(i);
FieldValue value = FieldValueUtil.refine(parameterField, values.get(i));
functionContext.declare(parameterField.getName(), value);
}
Expression expression = defineFunction.getExpression();
if (expression == null) {
throw new InvalidFeatureException(defineFunction);
}
FieldValue result = ExpressionUtil.evaluate(expression, functionContext);
return FieldValueUtil.refine(defineFunction.getDataType(), defineFunction.getOptype(), result);
}
private static void checkVariableArguments(
List<FieldValue> values, int size, boolean allowNulls) {
boolean success = (values.size() >= size) && (allowNulls ? true : !values.contains(null));
if (!success) {
throw new EvaluationException();
}
}
@Override
public FieldValue evaluate(List<FieldValue> values) {
if (values.size() != 2) {
throw new EvaluationException();
}
FieldValue left = values.get(0);
FieldValue right = values.get(1);
// "If one of the input fields of a simple arithmetic function is a missing value, the result
// evaluates to missing value"
if (left == null || right == null) {
return null;
}
DataType dataType = TypeUtil.getResultDataType(left.getDataType(), right.getDataType());
Number result;
try {
result = evaluate(left.asNumber(), right.asNumber());
} catch (ArithmeticException ae) {
throw new InvalidResultException(null);
}
return FieldValueUtil.create(cast(dataType, result));
}
@Override
public FieldValue evaluate(List<FieldValue> values) {
checkVariableArguments(values, 2);
Boolean result = evaluate(values.get(0), values.subList(1, values.size()));
return FieldValueUtil.create(result);
}
@Override
public FieldValue evaluate(List<FieldValue> values) {
checkVariableArguments(values, 2);
Boolean result = (values.get(0)).asBoolean();
for (int i = 1; i < values.size(); i++) {
result = evaluate(result, (values.get(i)).asBoolean());
}
return FieldValueUtil.create(result);
}