/// <summary> <p>
/// Parses a query, searching on the fields specified.
/// Use this if you need to specify certain fields as required,
/// and others as prohibited.
/// <p><pre>
/// Usage:
/// <code>
/// String[] fields = {"filename", "contents", "description"};
/// int[] flags = {MultiFieldQueryParser.NORMAL FIELD,
/// MultiFieldQueryParser.REQUIRED FIELD,
/// MultiFieldQueryParser.PROHIBITED FIELD,};
/// parse(query, fields, flags, analyzer);
/// </code>
/// </pre>
/// <p>
/// The code above would construct a query:
/// <pre>
/// <code>
/// (filename:query) +(contents:query) -(description:query)
/// </code>
/// </pre>
///
/// </summary>
/// <param name="query">Query string to parse
/// </param>
/// <param name="fields">Fields to search on
/// </param>
/// <param name="flags">Flags describing the fields
/// </param>
/// <param name="analyzer">Analyzer to use
/// </param>
/// <throws> ParseException if query parsing fails </throws>
/// <throws> TokenMgrError if query parsing fails </throws>
public static Query Parse(System.String query, System.String[] fields, int[] flags, Analyzer analyzer)
{
BooleanQuery bQuery = new BooleanQuery();
for (int i = 0; i < fields.Length; i++)
{
Query q = Parse(query, fields[i], analyzer);
int flag = flags[i];
switch (flag)
{
case REQUIRED_FIELD:
bQuery.Add(q, true, false);
break;
case PROHIBITED_FIELD:
bQuery.Add(q, false, true);
break;
default:
bQuery.Add(q, false, false);
break;
}
}
return(bQuery);
}
/// <summary> <p>
/// Parses a query which searches on the fields specified.
/// <p>
/// If x fields are specified, this effectively constructs:
/// <pre>
/// <code>
/// (field1:query) (field2:query) (field3:query)...(fieldx:query)
/// </code>
/// </pre>
///
/// </summary>
/// <param name="query">Query string to parse
/// </param>
/// <param name="fields">Fields to search on
/// </param>
/// <param name="analyzer">Analyzer to use
/// </param>
/// <throws> ParseException if query parsing fails </throws>
/// <throws> TokenMgrError if query parsing fails </throws>
public static Query Parse(System.String query, System.String[] fields, Analyzer analyzer)
{
BooleanQuery bQuery = new BooleanQuery();
for (int i = 0; i < fields.Length; i++)
{
Query q = Parse(query, fields[i], analyzer);
bQuery.Add(q, false, false);
}
return(bQuery);
}
public abstract Monodoc.Lucene.Net.Search.TopDocs Search(Monodoc.Lucene.Net.Search.Query param1, Monodoc.Lucene.Net.Search.Filter param2, int param3);
public abstract Monodoc.Lucene.Net.Search.Query Rewrite(Monodoc.Lucene.Net.Search.Query param1);
public abstract void Search(Monodoc.Lucene.Net.Search.Query param1, Monodoc.Lucene.Net.Search.Filter param2, Monodoc.Lucene.Net.Search.HitCollector param3);
public abstract Monodoc.Lucene.Net.Search.TopFieldDocs Search(Monodoc.Lucene.Net.Search.Query param1, Monodoc.Lucene.Net.Search.Filter param2, int param3, Monodoc.Lucene.Net.Search.Sort param4);
public abstract Monodoc.Lucene.Net.Search.Explanation Explain(Monodoc.Lucene.Net.Search.Query param1, int param2);
public virtual Explanation Explain(Monodoc.Lucene.Net.Index.IndexReader reader, int doc)
{
Explanation result = new Explanation();
result.SetDescription("weight(" + Query + " in " + doc + "), product of:");
System.String field = ((SpanQuery)Query).GetField();
System.Text.StringBuilder docFreqs = new System.Text.StringBuilder();
System.Collections.IEnumerator i = terms.GetEnumerator();
while (i.MoveNext())
{
Term term = (Term)i.Current;
docFreqs.Append(term.Text());
docFreqs.Append("=");
docFreqs.Append(searcher.DocFreq(term));
if (i.MoveNext())
{
docFreqs.Append(" ");
}
}
Explanation idfExpl = new Explanation(idf, "idf(" + field + ": " + docFreqs + ")");
// explain query weight
Explanation queryExpl = new Explanation();
queryExpl.SetDescription("queryWeight(" + Query + "), product of:");
Explanation boostExpl = new Explanation(Query.GetBoost(), "boost");
if (Query.GetBoost() != 1.0f)
{
queryExpl.AddDetail(boostExpl);
}
queryExpl.AddDetail(idfExpl);
Explanation queryNormExpl = new Explanation(queryNorm, "queryNorm");
queryExpl.AddDetail(queryNormExpl);
queryExpl.SetValue(boostExpl.GetValue() * idfExpl.GetValue() * queryNormExpl.GetValue());
result.AddDetail(queryExpl);
// explain Field weight
Explanation fieldExpl = new Explanation();
fieldExpl.SetDescription("fieldWeight(" + field + ":" + query.ToString(field) + " in " + doc + "), product of:");
Explanation tfExpl = Scorer(reader).Explain(doc);
fieldExpl.AddDetail(tfExpl);
fieldExpl.AddDetail(idfExpl);
Explanation fieldNormExpl = new Explanation();
byte[] fieldNorms = reader.Norms(field);
float fieldNorm = fieldNorms != null?Similarity.DecodeNorm(fieldNorms[doc]) : 0.0f;
fieldNormExpl.SetValue(fieldNorm);
fieldNormExpl.SetDescription("fieldNorm(Field=" + field + ", doc=" + doc + ")");
fieldExpl.AddDetail(fieldNormExpl);
fieldExpl.SetValue(tfExpl.GetValue() * idfExpl.GetValue() * fieldNormExpl.GetValue());
result.AddDetail(fieldExpl);
// combine them
result.SetValue(queryExpl.GetValue() * fieldExpl.GetValue());
if (queryExpl.GetValue() == 1.0f)
{
return(fieldExpl);
}
return(result);
}
