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// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
#pragma once
#include <vespa/searchlib/common/feature.h>
#include <vespa/searchlib/fef/iqueryenvironment.h>
#include <vespa/searchlib/fef/itermdata.h>
namespace search::features {
/**
* This class represents a query term with the relevant data. Now also
* with an optional attachment of a TermFieldData pointer.
*/
class QueryTerm {
private:
const fef::ITermData *_termData;
fef::TermFieldHandle _handle;
feature_t _significance;
feature_t _connectedness;
public:
QueryTerm()
: _termData(nullptr),
_handle(fef::IllegalHandle),
_significance(0),
_connectedness(0)
{ }
QueryTerm(const fef::ITermData *td, feature_t sig = 0, feature_t con = 0)
: _termData(td),
_handle(fef::IllegalHandle),
_significance(sig),
_connectedness(con)
{ }
const fef::ITermData *termData() const { return _termData; }
feature_t significance() const { return _significance; }
feature_t connectedness() const { return _connectedness; }
fef::TermFieldHandle fieldHandle() const { return _handle; }
void fieldHandle(fef::TermFieldHandle handle) { _handle = handle; }
void fieldHandle(const fef::ITermFieldData *fd) {
if (fd) {
_handle = fd->getHandle();
}
}
};
/**
* Convenience typedef for a vector of QueryTerm objects.
*/
using QueryTermVector = std::vector<QueryTerm>;
/**
* This class is a factory for creating QueryTerm objects.
*/
class QueryTermFactory {
public:
/**
* Creates a new QueryTerm object for the term with the given term index.
*
* @param env the environment used to lookup TermData object, significance, and connectedness.
* @param termIndex the index to use when looking up the TermData object.
* @param lookupConnectedness whether we should look up the connectedness this term has with the previous term.
*/
static QueryTerm create(const fef::IQueryEnvironment & env, uint32_t termIndex, bool lookupConnectedness = false);
};
/**
* Helper class to allow simple reuse of processed QueryTermVector
* containing all terms in the query. Primary reason is to reduce expensive recomputation
* when multiple features need the same and also only compute it once per query and one once per search thread.
*/
class QueryTermHelper {
public:
QueryTermHelper(const fef::IQueryEnvironment & env);
const QueryTermVector & terms() const { return *_queryTerms; }
static const QueryTermVector & lookupAndStoreQueryTerms(const fef::IQueryEnvironment & env, fef::IObjectStore & objectStore);
private:
static const QueryTermVector * lookupQueryTerms(const fef::IQueryEnvironment & env);
static QueryTermVector createQueryTermvector(const fef::IQueryEnvironment & env);
QueryTermVector _fallBack;
const QueryTermVector * _queryTerms;
};
}
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