/// <summary>
/// Generates syntax for an invoke method.
/// </summary>
/// <param name="grainType">
/// The grain type.
/// </param>
/// <param name="invokeMethod">
/// The invoke method to generate.
/// </param>
/// <returns>
/// Syntax for an invoke method.
/// </returns>
private static MethodDeclarationSyntax GenerateInvokeMethod(Type grainType, MethodInfo invokeMethod)
{
var methodDeclaration = invokeMethod.GetDeclarationSyntax();
var parameters = invokeMethod.GetParameters();
var grainArgument = parameters[0].Name.ToIdentifierName();
var interfaceIdArgument = parameters[1].Name.ToIdentifierName();
var methodIdArgument = parameters[2].Name.ToIdentifierName();
var argumentsArgument = parameters[3].Name.ToIdentifierName();
var interfaceCases = CodeGeneratorCommon.GenerateGrainInterfaceAndMethodSwitch(
grainType,
methodIdArgument,
methodType => GenerateInvokeForMethod(grainType, grainArgument, methodType, argumentsArgument));
// Generate the default case, which will throw a NotImplementedException.
var errorMessage = SF.BinaryExpression(
SyntaxKind.AddExpression,
"interfaceId=".GetLiteralExpression(),
interfaceIdArgument);
var throwStatement =
SF.ThrowStatement(
SF.ObjectCreationExpression(typeof(NotImplementedException).GetTypeSyntax())
.AddArgumentListArguments(SF.Argument(errorMessage)));
var defaultCase = SF.SwitchSection().AddLabels(SF.DefaultSwitchLabel()).AddStatements(throwStatement);
var interfaceIdSwitch =
SF.SwitchStatement(interfaceIdArgument).AddSections(interfaceCases.ToArray()).AddSections(defaultCase);
// If the provided grain is null, throw an argument exception.
var argumentNullException =
SF.ObjectCreationExpression(typeof(ArgumentNullException).GetTypeSyntax())
.AddArgumentListArguments(SF.Argument(parameters[0].Name.GetLiteralExpression()));
var grainArgumentCheck =
SF.IfStatement(
SF.BinaryExpression(
SyntaxKind.EqualsExpression,
grainArgument,
SF.LiteralExpression(SyntaxKind.NullLiteralExpression)),
SF.ThrowStatement(argumentNullException));
// Wrap everything in a try-catch block.
var faulted = (Expression <Func <Task <object> > >)(() => TaskUtility.Faulted(null));
const string Exception = "exception";
var exception = SF.Identifier(Exception);
var body =
SF.TryStatement()
.AddBlockStatements(grainArgumentCheck, interfaceIdSwitch)
.AddCatches(
SF.CatchClause()
.WithDeclaration(
SF.CatchDeclaration(typeof(Exception).GetTypeSyntax()).WithIdentifier(exception))
.AddBlockStatements(
SF.ReturnStatement(
faulted.Invoke().AddArgumentListArguments(SF.Argument(SF.IdentifierName(Exception))))));
return(methodDeclaration.AddBodyStatements(body));
}
