org.apache.lucene.search
Class ScoringRewrite<Q extends Query>
java.lang.Object
org.apache.lucene.search.MultiTermQuery.RewriteMethod
org.apache.lucene.search.ScoringRewrite<Q>
- All Implemented Interfaces:
- Serializable
public abstract class ScoringRewrite<Q extends Query>
- extends MultiTermQuery.RewriteMethod
- See Also:
- Serialized Form
- NOTE: This API is for internal purposes only and might change in incompatible ways in the next release.
- Only public to be accessible by spans package.
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
SCORING_BOOLEAN_QUERY_REWRITE
public static final ScoringRewrite<BooleanQuery> SCORING_BOOLEAN_QUERY_REWRITE
- A rewrite method that first translates each term into
BooleanClause.Occur.SHOULD
clause in a
BooleanQuery, and keeps the scores as computed by the
query. Note that typically such scores are
meaningless to the user, and require non-trivial CPU
to compute, so it's almost always better to use MultiTermQuery.CONSTANT_SCORE_AUTO_REWRITE_DEFAULT
instead.
NOTE: This rewrite method will hit BooleanQuery.TooManyClauses
if the number of terms
exceeds BooleanQuery.getMaxClauseCount()
.
- See Also:
MultiTermQuery.setRewriteMethod(org.apache.lucene.search.MultiTermQuery.RewriteMethod)
CONSTANT_SCORE_BOOLEAN_QUERY_REWRITE
public static final MultiTermQuery.RewriteMethod CONSTANT_SCORE_BOOLEAN_QUERY_REWRITE
- Like
SCORING_BOOLEAN_QUERY_REWRITE
except
scores are not computed. Instead, each matching
document receives a constant score equal to the
query's boost.
NOTE: This rewrite method will hit BooleanQuery.TooManyClauses
if the number of terms
exceeds BooleanQuery.getMaxClauseCount()
.
- See Also:
MultiTermQuery.setRewriteMethod(org.apache.lucene.search.MultiTermQuery.RewriteMethod)
ScoringRewrite
public ScoringRewrite()
rewrite
public Q rewrite(IndexReader reader,
MultiTermQuery query)
throws IOException
- Specified by:
rewrite
in class MultiTermQuery.RewriteMethod
- Throws:
IOException
getTopLevelQuery
protected abstract Q getTopLevelQuery()
throws IOException
- Return a suitable top-level Query for holding all expanded terms.
- Throws:
IOException
addClause
protected abstract void addClause(Q topLevel,
Term term,
float boost)
throws IOException
- Add a MultiTermQuery term to the top-level query
- Throws:
IOException
collectTerms
protected final void collectTerms(IndexReader reader,
MultiTermQuery query,
TermCollectingRewrite.TermCollector collector)
throws IOException
- Throws:
IOException
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