Namespace Lucene.Net.QueryParsers.Surround.Query 

This package contains SrndQuery and its subclasses.

The parser in the org.apache.lucene.queryparser.surround.parser package
normally generates a SrndQuery.

For searching an org.apache.lucene.search.Query is provided by
the SrndQuery.makeLuceneQueryField method.
For this, TermQuery, BooleanQuery and SpanQuery are used from Lucene.

Classes

AndQuery

Factory for conjunctions

BasicQueryFactory

Factory for creating basic term queries

ComposedQuery

Base class for composite queries (such as AND/OR/NOT)

DistanceQuery

Factory for NEAR queries

FieldsQuery

Forms an OR query of the provided query across multiple fields.

NotQuery

Factory for prohibited clauses

OrQuery

Factory for disjunctions

SimpleTerm

Base class for queries that expand to sets of simple terms.

SpanNearClauseFactory

SpanNearClauseFactory:

Operations:

  • create for a field name and an indexreader.
  • add a weighted Term - this should add a corresponding SpanTermQuery, or increase the weight of an existing one.
  • add a weighted subquery SpanNearQuery
  • create a clause for SpanNearQuery from the things added above.

For this, create an array of SpanQuery's from the added ones. The clause normally is a SpanOrQuery over the added subquery SpanNearQuery the SpanTermQuery's for the added Term's

When it is necessary to suppress double subqueries as much as possible: GetHashCode() and Equals() on unweighted SpanQuery are needed (possibly via GetTerms(), the terms are individually hashable). Idem SpanNearQuery: hash on the subqueries and the slop. Evt. merge SpanNearQuery's by adding the weights of the corresponding subqueries.

To be determined: Are SpanQuery weights handled correctly during search by Lucene? Should the resulting SpanOrQuery be sorted? Could other SpanQueries be added for use in this factory:

  • SpanOrQuery: in principle yes, but it only has access to it's terms via getTerms(); are the corresponding weights available?
  • SpanFirstQuery: treat similar to subquery SpanNearQuery. (ok?)
  • SpanNotQuery: treat similar to subquery SpanNearQuery. (ok?)

Factory for

SrndPrefixQuery

Query that matches string prefixes

SrndQuery

Lowest level base class for surround queries

SrndTermQuery

Simple single-term clause

SrndTruncQuery

Query that matches wildcards

TooManyBasicQueries

Exception thrown when BasicQueryFactory would exceed the limit of query clauses.

Interfaces

IDistanceSubQuery

Interface for queries that can be nested as subqueries into a span near.

SimpleTerm.IMatchingTermVisitor

Callback to visit each matching term during "rewrite" in VisitMatchingTerm(Term)