public AggregationTAAReaderLinearFirstLastForge(
Type underlyingType,
AggregationAccessorLinearType accessType,
ExprNode optionalEvaluator)
{
ResultType = underlyingType;
this.accessType = accessType;
this.optionalEvaluator = optionalEvaluator;
}
private AggregationMultiFunctionMethodDesc HandleMethodFirstLast(
ExprNode[] childNodes,
AggregationAccessorLinearType methodType,
ExprValidationContext validationContext)
{
var underlyingType = ContainedEventType.UnderlyingType;
if (childNodes.Length == 0) {
var forge = new AggregationMethodLinearFirstLastForge(underlyingType, methodType, null);
return new AggregationMultiFunctionMethodDesc(forge, null, null, ContainedEventType);
}
if (childNodes.Length == 1) {
if (childNodes[0] is ExprWildcard) {
var forgeX = new AggregationMethodLinearFirstLastForge(underlyingType, methodType, null);
return new AggregationMultiFunctionMethodDesc(forgeX, null, null, ContainedEventType);
}
if (childNodes[0] is ExprStreamUnderlyingNode) {
throw new ExprValidationException("Stream-wildcard is not allowed for table column access");
}
// Expressions apply to events held, thereby validate in terms of event value expressions
var paramNode = childNodes[0];
var streams = TableCompileTimeUtil.StreamTypeFromTableColumn(ContainedEventType);
var localValidationContext = new ExprValidationContext(streams, validationContext);
paramNode = ExprNodeUtilityValidate.GetValidatedSubtree(ExprNodeOrigin.AGGPARAM, paramNode, localValidationContext);
var forge = new AggregationMethodLinearFirstLastForge(paramNode.Forge.EvaluationType, methodType, paramNode);
return new AggregationMultiFunctionMethodDesc(forge, null, null, null);
}
if (childNodes.Length == 2) {
int? constant = null;
var indexEvalNode = childNodes[1];
var indexEvalType = indexEvalNode.Forge.EvaluationType;
if (indexEvalType != typeof(int?) && indexEvalType != typeof(int)) {
throw new ExprValidationException(GetErrorPrefix(methodType) + " requires a constant index expression that returns an integer value");
}
ExprNode indexExpr;
if (indexEvalNode.Forge.ForgeConstantType == ExprForgeConstantType.COMPILETIMECONST) {
constant = indexEvalNode.Forge.ExprEvaluator.Evaluate(null, true, null).AsBoxedInt32();
indexExpr = null;
}
else {
indexExpr = indexEvalNode;
}
var forge = new AggregationMethodLinearFirstLastIndexForge(
underlyingType,
methodType,
constant,
indexExpr);
return new AggregationMultiFunctionMethodDesc(forge, null, null, ContainedEventType);
}
throw new ExprValidationException("Invalid number of parameters");
}
public AggregationMethodLinearFirstLastForge(
Type underlyingType,
AggregationAccessorLinearType accessType,
ExprNode optionalEvaluator)
{
this.underlyingType = underlyingType;
this.accessType = accessType;
this.optionalEvaluator = optionalEvaluator;
}
public AggregationMethodLinearFirstLastIndexForge(
Type underlyingType,
AggregationAccessorLinearType accessType,
int? optionalConstant,
ExprNode optionalIndexEval)
{
this.underlyingType = underlyingType;
this.accessType = accessType;
this.optionalConstant = optionalConstant;
this.optionalIndexEval = optionalIndexEval;
}
/// <summary>
/// Gets the name.
/// </summary>
public static string GetName(this AggregationAccessorLinearType value)
{
switch (value)
{
case AggregationAccessorLinearType.FIRST:
return "FIRST";
case AggregationAccessorLinearType.LAST:
return "LAST";
case AggregationAccessorLinearType.WINDOW:
return "WINDOW";
default:
throw new ArgumentOutOfRangeException(nameof(value), value, null);
}
}
private static String GetErrorPrefix(AggregationAccessorLinearType stateType)
{
return ExprAggMultiFunctionUtil.GetErrorPrefix(stateType.ToString().ToLowerInvariant());
}