feature-extractor.H

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#ifndef RERANKER_FEATURE_EXTRACTOR_H_
#define RERANKER_FEATURE_EXTRACTOR_H_

#include <string>
#include <memory>
#include <unordered_map>

#include "feature-vector.H"
#include "candidate.H"
#include "candidate-set.H"
#include "factory.H"

namespace reranker {

using std::string;
using std::shared_ptr;
using std::unordered_map;

void TearDown();

class FeatureExtractor : public FactoryConstructible {
 public:
  FeatureExtractor() {}
  virtual ~FeatureExtractor() {}

  virtual void Extract(Candidate &candidate,
                       FeatureVector<int,double> &features) = 0;

  virtual void ExtractSymbolic(Candidate &candidate,
                               FeatureVector<string,double> &symbolic_features)
  = 0;

  virtual void Reset() {
  }

  virtual void Extract(CandidateSet &candidate_set) {
    for (CandidateSet::iterator it = candidate_set.begin();
         it != candidate_set.end();
         ++it) {
      Candidate &candidate = *(*it);
      Extract(candidate, candidate.mutable_features());
      ExtractSymbolic(candidate, candidate.mutable_symbolic_features());
    }
  }
};

#define REGISTER_NAMED_FEATURE_EXTRACTOR(TYPE,NAME) \
  REGISTER_NAMED(TYPE,NAME,FeatureExtractor)

#define REGISTER_FEATURE_EXTRACTOR(TYPE) \
  REGISTER_NAMED_FEATURE_EXTRACTOR(TYPE,TYPE)

}  // namespace reranker

#endif