/**
* The sum of squared weights of contained query clauses.
*
* @return float
*/
public function sumOfSquaredWeights()
{
// compute idf
$this->_idf = $this->_reader->getSimilarity()->idf($this->_query->getTerms(), $this->_reader);
// compute query weight
$this->_queryWeight = $this->_idf * $this->_query->getBoost();
// square it
return $this->_queryWeight * $this->_queryWeight;
}
/**
* Re-write query into primitive queries in the context of specified index
*
* @param \ZendSearch\Lucene\SearchIndexInterface $index
* @return \ZendSearch\Lucene\Search\Query\AbstractQuery
*/
public function rewrite(Lucene\SearchIndexInterface $index)
{
// Allow to use wildcards within phrases
// They are either removed by text analyzer or used as a part of keyword for keyword fields
//
// if (strpos($this->_phrase, '?') !== false || strpos($this->_phrase, '*') !== false) {
// require_once 'Zend/Search/Lucene/Search/QueryParserException.php';
// throw new Zend_Search_Lucene_Search_QueryParserException('Wildcards are only allowed in a single terms.');
// }
// Split query into subqueries if field name is not specified
if ($this->_field === null) {
$query = new Query\Boolean();
$query->setBoost($this->getBoost());
if (Lucene\Lucene::getDefaultSearchField() === null) {
$searchFields = $index->getFieldNames(true);
} else {
$searchFields = array(Lucene\Lucene::getDefaultSearchField());
}
foreach ($searchFields as $fieldName) {
$subquery = new Phrase($this->_phrase, $this->_phraseEncoding, $fieldName);
$subquery->setSlop($this->getSlop());
$query->addSubquery($subquery->rewrite($index));
}
$this->_matches = $query->getQueryTerms();
return $query;
}
// Recognize exact term matching (it corresponds to Keyword fields stored in the index)
// encoding is not used since we expect binary matching
$term = new Index\Term($this->_phrase, $this->_field);
if ($index->hasTerm($term)) {
$query = new Query\Term($term);
$query->setBoost($this->getBoost());
$this->_matches = $query->getQueryTerms();
return $query;
}
// tokenize phrase using current analyzer and process it as a phrase query
$tokens = Analyzer::getDefault()->tokenize($this->_phrase, $this->_phraseEncoding);
if (count($tokens) == 0) {
$this->_matches = array();
return new Query\Insignificant();
}
if (count($tokens) == 1) {
$term = new Index\Term($tokens[0]->getTermText(), $this->_field);
$query = new Query\Term($term);
$query->setBoost($this->getBoost());
$this->_matches = $query->getQueryTerms();
return $query;
}
//It's non-trivial phrase query
$position = -1;
$query = new Query\Phrase();
foreach ($tokens as $token) {
$position += $token->getPositionIncrement();
$term = new Index\Term($token->getTermText(), $this->_field);
$query->addTerm($term, $position);
$query->setSlop($this->getSlop());
}
$this->_matches = $query->getQueryTerms();
return $query;
}
