| using System.Collections.Generic; |
| using Lucene.Net.Index; |
| using Lucene.Net.Search; |
| using Lucene.Net.Util; |
| |
| namespace Lucene.Net.Join |
| { |
| /* |
| * Licensed to the Apache Software Foundation (ASF) under one or more |
| * contributor license agreements. See the NOTICE file distributed with |
| * this work for additional information regarding copyright ownership. |
| * The ASF licenses this file to You under the Apache License, Version 2.0 |
| * (the "License"); you may not use this file except in compliance with |
| * the License. You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| /// <summary> |
| /// A query that has an array of terms from a specific field. This query will match documents have one or more terms in |
| /// the specified field that match with the terms specified in the array. |
| /// |
| /// @lucene.experimental |
| /// </summary> |
| internal class TermsQuery : MultiTermQuery |
| { |
| private readonly BytesRefHash _terms; |
| private readonly int[] _ords; |
| private readonly Query _fromQuery; // Used for equals() only |
| |
| /// <summary> |
| /// |
| /// </summary> |
| /// <param name="field">The field that should contain terms that are specified in the previous parameter.</param> |
| /// <param name="fromQuery"></param> |
| /// <param name="terms">The terms that matching documents should have. The terms must be sorted by natural order.</param> |
| internal TermsQuery(string field, Query fromQuery, BytesRefHash terms) |
| : base(field) |
| { |
| _fromQuery = fromQuery; |
| _terms = terms; |
| _ords = terms.Sort(BytesRef.UTF8SortedAsUnicodeComparer); |
| } |
| |
| protected override TermsEnum GetTermsEnum(Terms terms, AttributeSource atts) |
| { |
| if (_terms.Count == 0) |
| { |
| return TermsEnum.EMPTY; |
| } |
| |
| return new SeekingTermSetTermsEnum(terms.GetEnumerator(), _terms, _ords); |
| |
| } |
| |
| public override string ToString(string field) |
| { |
| return string.Format("TermsQuery{{field={0}}}", field); |
| } |
| |
| public override bool Equals(object obj) |
| { |
| if (this == obj) |
| { |
| return true; |
| } |
| if (!base.Equals(obj)) |
| { |
| return false; |
| } |
| if (GetType() != obj.GetType()) |
| { |
| return false; |
| } |
| |
| TermsQuery other = (TermsQuery)obj; |
| if (!_fromQuery.Equals(other._fromQuery)) |
| { |
| return false; |
| } |
| return true; |
| } |
| |
| public override int GetHashCode() |
| { |
| int prime = 31; |
| int result = base.GetHashCode(); |
| result += prime * _fromQuery.GetHashCode(); |
| return result; |
| } |
| |
| private class SeekingTermSetTermsEnum : FilteredTermsEnum |
| { |
| private readonly BytesRefHash terms; |
| private readonly int[] ords; |
| private readonly int _lastElement; |
| |
| private readonly BytesRef _lastTerm; |
| private readonly BytesRef _spare = new BytesRef(); |
| private readonly IComparer<BytesRef> _comparer; |
| |
| private BytesRef _seekTerm; |
| private int _upto; |
| |
| internal SeekingTermSetTermsEnum(TermsEnum tenum, BytesRefHash terms, int[] ords) |
| : base(tenum) |
| { |
| this.terms = terms; |
| this.ords = ords; |
| _comparer = BytesRef.UTF8SortedAsUnicodeComparer; |
| _lastElement = terms.Count - 1; |
| _lastTerm = terms.Get(ords[_lastElement], new BytesRef()); |
| _seekTerm = terms.Get(ords[_upto], _spare); |
| } |
| |
| protected override BytesRef NextSeekTerm(BytesRef currentTerm) |
| { |
| BytesRef temp = _seekTerm; |
| _seekTerm = null; |
| return temp; |
| } |
| |
| protected override AcceptStatus Accept(BytesRef term) |
| { |
| if (_comparer.Compare(term, _lastTerm) > 0) |
| { |
| return AcceptStatus.END; |
| } |
| |
| BytesRef currentTerm = terms.Get(ords[_upto], _spare); |
| if (_comparer.Compare(term, currentTerm) == 0) |
| { |
| if (_upto == _lastElement) |
| { |
| return AcceptStatus.YES; |
| } |
| |
| _seekTerm = terms.Get(ords[++_upto], _spare); |
| return AcceptStatus.YES_AND_SEEK; |
| } |
| |
| if (_upto == _lastElement) |
| { |
| return AcceptStatus.NO; |
| } // Our current term doesn't match the the given term. |
| |
| int cmp; |
| do // We maybe are behind the given term by more than one step. Keep incrementing till we're the same or higher. |
| { |
| if (_upto == _lastElement) |
| { |
| return AcceptStatus.NO; |
| } |
| // typically the terms dict is a superset of query's terms so it's unusual that we have to skip many of |
| // our terms so we don't do a binary search here |
| _seekTerm = terms.Get(ords[++_upto], _spare); |
| } while ((cmp = _comparer.Compare(_seekTerm, term)) < 0); |
| if (cmp == 0) |
| { |
| if (_upto == _lastElement) |
| { |
| return AcceptStatus.YES; |
| } |
| _seekTerm = terms.Get(ords[++_upto], _spare); |
| return AcceptStatus.YES_AND_SEEK; |
| } |
| |
| return AcceptStatus.NO_AND_SEEK; |
| } |
| } |
| } |
| } |