private static LuceneQuery GetLuceneBoostQuery(this CommutativeExpression expression, string fieldName, Analyzer analyzer)
{
var query = new BooleanQuery();
foreach (var innerQuery in expression.Terms.Select(t => t.GetLuceneBoostQuery(fieldName, analyzer)))
{
if (innerQuery != null)
{
query.add(innerQuery, BooleanClause.Occur.SHOULD);
}
}
return(query);
}
private static LuceneQuery GetLuceneQuery(this CommutativeExpression expression, string fieldName, Analyzer analyzer)
{
BooleanClause.Occur defaultOp;
switch (expression.Operator)
{
case BinaryOperator.And:
defaultOp = BooleanClause.Occur.MUST;
break;
case BinaryOperator.Or:
defaultOp = BooleanClause.Occur.SHOULD;
break;
default:
throw new InvalidOperationException();
}
var query = new BooleanQuery();
foreach (var term in expression.Terms)
{
var op = defaultOp;
var innerExpr = term;
var unaryTerm = term as UnaryExpression;
if (unaryTerm != null)
{
if (expression.Operator != BinaryOperator.And)
{
continue;
}
op = BooleanClause.Occur.MUST_NOT;
innerExpr = unaryTerm.Term;
}
var innerQuery = innerExpr.GetLuceneQuery(fieldName, analyzer);
if (innerQuery != null)
{
query.add(innerQuery, op);
}
}
return(query);
}