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Diffstat (limited to 'trunk/TAO/orbsvcs/orbsvcs/Trader/Constraint_Interpreter.h')
| -rw-r--r-- | trunk/TAO/orbsvcs/orbsvcs/Trader/Constraint_Interpreter.h | 166 |
1 files changed, 166 insertions, 0 deletions
diff --git a/trunk/TAO/orbsvcs/orbsvcs/Trader/Constraint_Interpreter.h b/trunk/TAO/orbsvcs/orbsvcs/Trader/Constraint_Interpreter.h new file mode 100644 index 00000000000..586f82080e4 --- /dev/null +++ b/trunk/TAO/orbsvcs/orbsvcs/Trader/Constraint_Interpreter.h @@ -0,0 +1,166 @@ +/* -*- C++ -*- */ + +//============================================================================= +/** + * @file Constraint_Interpreter.h + * + * $Id$ + * + * @author Seth Widoff <sbw1@cs.wustl.edu> + */ +//============================================================================= + + +#ifndef TAO_CONSTRAINT_INTERPRETER_H +#define TAO_CONSTRAINT_INTERPRETER_H +#include /**/ "ace/pre.h" + +#include "orbsvcs/Trader/Constraint_Nodes.h" +#include "orbsvcs/Trader/Constraint_Visitors.h" +#include "orbsvcs/Trader/Interpreter.h" + +#include "orbsvcs/CosTradingS.h" +#include "orbsvcs/CosTradingReposS.h" + +TAO_BEGIN_VERSIONED_NAMESPACE_DECL + +class TAO_Constraint_Evaluator; +class TAO_Constraint_Validator; + +/** + * @class TAO_Constraint_Interpreter + * + * @brief TAO_Constraint_Interpreter will, given a constraint string whose + * syntax and semantics comply with the trader specification for the + * constraint language, determine if a CosTrading::Offer meets the + * constraints. + * + * TAO_Constraint_Interpreter will first build an expression tree + * representing the constraint expression using Lex and Yacc. Then, + * using a TAO_Constraint_Validator, it will validate the semantic + * correctness of the tree. When the evaluate method is invoked with + * an Offer, the TAO_Constraint_Interpreter will construct an + * EvaluationVisitor, which will evaluate the tree and decide + * whether the offer meets the constraints. + */ +class TAO_Trading_Serv_Export TAO_Constraint_Interpreter : public TAO_Interpreter +{ +public: + // = Initialization and termination methods. + TAO_Constraint_Interpreter (const CosTradingRepos::ServiceTypeRepository::TypeStruct& ts, + const char* constraints + ACE_ENV_ARG_DECL) + ACE_THROW_SPEC ((CosTrading::IllegalConstraint, + CORBA::NO_MEMORY)); + + /** + * This constructor builds an expression tree representing the + * constraint specified in <constraints>, and throws an Illegal + * Constraint exception if the constraint given has syntax errors or + * semantic errors, such as mismatched types. + */ + TAO_Constraint_Interpreter (TAO_Constraint_Validator& validator, + const char* constraints + ACE_ENV_ARG_DECL) + ACE_THROW_SPEC ((CosTrading::IllegalConstraint, + CORBA::NO_MEMORY)); + + /// Destructor + ~TAO_Constraint_Interpreter (void); + + CORBA::Boolean evaluate (CosTrading::Offer* offer); + + CORBA::Boolean evaluate (TAO_Constraint_Evaluator& evaluator); + + // Determine whether an offer fits the constraints with which the + // tree was constructed. This method is thread safe (hopefully). +}; + +/** + * @class TAO_Preference_Interpreter + * + * @brief The TAO_Preference_Interpreter will, given a valid preference + * string and offers, will order the offers based on the offers' + * compliance with the preferences. + * + * Each time the order_offer method is invoked, the + * TAO_Preference_Interpreter stores the offer reference in the + * order dictated by its evaluation of the preference string. After + * the TAO_Preference_Interpreter client has finished ordering all + * the offers, it will extract the offers in order using the + * remove_offer method. + */ +class TAO_Trading_Serv_Export TAO_Preference_Interpreter : public TAO_Interpreter +{ +public: + // = Initialization and termination methods. + TAO_Preference_Interpreter (const CosTradingRepos::ServiceTypeRepository::TypeStruct& ts, + const char* preference + ACE_ENV_ARG_DECL) + ACE_THROW_SPEC ((CosTrading::Lookup::IllegalPreference, + CORBA::NO_MEMORY)); + + /** + * Parse the preference string, determining first if it's + * valid. Throw an IllegalPreference exception if the preference + * doesn't conform to the BNF grammar for preferences. + */ + TAO_Preference_Interpreter (TAO_Constraint_Validator& validator, + const char* preference + ACE_ENV_ARG_DECL) + ACE_THROW_SPEC ((CosTrading::Lookup::IllegalPreference, + CORBA::NO_MEMORY)); + + /// Destructor + ~TAO_Preference_Interpreter(void); + + void order_offer (CosTrading::Offer* offer, + CosTrading::OfferId offer_id = 0); + + /// Evaluate the offer, and order it internally based on the results + /// of the evaluation. + void order_offer (TAO_Constraint_Evaluator& evaluator, + CosTrading::Offer* offer, + CosTrading::OfferId offer_id = 0); + + int remove_offer (CosTrading::Offer*& offer, + CosTrading::OfferId& offer_id); + + /// Remove the next offer. The offer returned will be the next in the + /// ordering determined by the preference string. + int remove_offer (CosTrading::Offer*& offer); + + /// Return the number of offers remaining in the ordering. + size_t num_offers (void); + + struct Preference_Info + { + /// True if the preference evaluation didn't return an error for this offer. + CORBA::Boolean evaluated_; + + /// The value of the preference evaluation. + TAO_Literal_Constraint value_; + + /// The offer id of this offer. + CosTrading::OfferId offer_id_; + + /// A pointer to the offer. + CosTrading::Offer* offer_; + }; + + typedef ACE_Unbounded_Queue<Preference_Info> Ordered_Offers; + +private: + + /// Disallow copying. + TAO_Preference_Interpreter (const TAO_Preference_Interpreter&); + TAO_Preference_Interpreter& operator= (const TAO_Preference_Interpreter&); + + /// The ordered list of offers. + Ordered_Offers offers_; +}; + +TAO_END_VERSIONED_NAMESPACE_DECL + +#include /**/ "ace/post.h" +#endif /* TAO_CONSTRAINT_INTERPRETER_H */ |