| using Lucene.Net.Util; |
| using System.Collections.Generic; |
| using System.Linq; |
| using System.Text; |
| |
| namespace Lucene.Net.Index |
| { |
| /* |
| * 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 <see cref="FilterAtomicReader"/> that exposes only a subset |
| /// of fields from the underlying wrapped reader. |
| /// </summary> |
| public sealed class FieldFilterAtomicReader : FilterAtomicReader |
| { |
| private readonly ISet<string> fields; |
| private readonly bool negate; |
| private readonly FieldInfos fieldInfos; |
| |
| public FieldFilterAtomicReader(AtomicReader @in, ISet<string> fields, bool negate) |
| : base(@in) |
| { |
| this.fields = fields; |
| this.negate = negate; |
| List<FieldInfo> filteredInfos = new List<FieldInfo>(); |
| foreach (FieldInfo fi in @in.FieldInfos) |
| { |
| if (HasField(fi.Name)) |
| { |
| filteredInfos.Add(fi); |
| } |
| } |
| fieldInfos = new FieldInfos(filteredInfos.ToArray()); |
| } |
| |
| internal bool HasField(string field) |
| { |
| return negate ^ fields.Contains(field); |
| } |
| |
| public override FieldInfos FieldInfos => fieldInfos; |
| |
| public override Fields GetTermVectors(int docID) |
| { |
| Fields f = base.GetTermVectors(docID); |
| if (f == null) |
| { |
| return null; |
| } |
| f = new FieldFilterFields(this, f); |
| // we need to check for emptyness, so we can return |
| // null: |
| using var iter = f.GetEnumerator(); |
| return iter.MoveNext() ? f : null; |
| } |
| |
| public override void Document(int docID, StoredFieldVisitor visitor) |
| { |
| base.Document(docID, new StoredFieldVisitorAnonymousClass(this, visitor)); |
| } |
| |
| private class StoredFieldVisitorAnonymousClass : StoredFieldVisitor |
| { |
| private readonly FieldFilterAtomicReader outerInstance; |
| |
| private readonly StoredFieldVisitor visitor; |
| |
| public StoredFieldVisitorAnonymousClass(FieldFilterAtomicReader outerInstance, StoredFieldVisitor visitor) |
| { |
| this.outerInstance = outerInstance; |
| this.visitor = visitor; |
| } |
| |
| public override void BinaryField(FieldInfo fieldInfo, byte[] value) |
| { |
| visitor.BinaryField(fieldInfo, value); |
| } |
| |
| public override void StringField(FieldInfo fieldInfo, string value) |
| { |
| visitor.StringField(fieldInfo, value); |
| } |
| |
| public override void Int32Field(FieldInfo fieldInfo, int value) |
| { |
| visitor.Int32Field(fieldInfo, value); |
| } |
| |
| public override void Int64Field(FieldInfo fieldInfo, long value) |
| { |
| visitor.Int64Field(fieldInfo, value); |
| } |
| |
| public override void SingleField(FieldInfo fieldInfo, float value) |
| { |
| visitor.SingleField(fieldInfo, value); |
| } |
| |
| public override void DoubleField(FieldInfo fieldInfo, double value) |
| { |
| visitor.DoubleField(fieldInfo, value); |
| } |
| |
| public override Status NeedsField(FieldInfo fieldInfo) |
| { |
| return outerInstance.HasField(fieldInfo.Name) ? visitor.NeedsField(fieldInfo) : Status.NO; |
| } |
| } |
| |
| public override Fields Fields |
| { |
| get |
| { |
| Fields f = base.Fields; |
| return (f == null) ? null : new FieldFilterFields(this, f); |
| } |
| } |
| |
| public override NumericDocValues GetNumericDocValues(string field) |
| { |
| return HasField(field) ? base.GetNumericDocValues(field) : null; |
| } |
| |
| public override BinaryDocValues GetBinaryDocValues(string field) |
| { |
| return HasField(field) ? base.GetBinaryDocValues(field) : null; |
| } |
| |
| public override SortedDocValues GetSortedDocValues(string field) |
| { |
| return HasField(field) ? base.GetSortedDocValues(field) : null; |
| } |
| |
| public override NumericDocValues GetNormValues(string field) |
| { |
| return HasField(field) ? base.GetNormValues(field) : null; |
| } |
| |
| public override IBits GetDocsWithField(string field) |
| { |
| return HasField(field) ? base.GetDocsWithField(field) : null; |
| } |
| |
| public override string ToString() |
| { |
| StringBuilder sb = new StringBuilder("FieldFilterAtomicReader(reader="); |
| sb.Append(m_input).Append(", fields="); |
| if (negate) |
| { |
| sb.Append('!'); |
| } |
| return sb.Append(fields).Append(')').ToString(); |
| } |
| |
| private class FieldFilterFields : FilterFields |
| { |
| private readonly FieldFilterAtomicReader outerInstance; |
| |
| public FieldFilterFields(FieldFilterAtomicReader outerInstance, Fields @in) |
| : base(@in) |
| { |
| this.outerInstance = outerInstance; |
| } |
| |
| // this information is not cheap, return -1 like MultiFields does: |
| public override int Count => -1; |
| |
| public override IEnumerator<string> GetEnumerator() |
| { |
| // LUCENENET: Performance is better and code simpler with simple where clause |
| // and yield return. |
| foreach (var field in m_input.Where((f) => outerInstance.HasField(f))) |
| yield return field; |
| } |
| |
| public override Terms GetTerms(string field) |
| { |
| return outerInstance.HasField(field) ? base.GetTerms(field) : null; |
| } |
| } |
| } |
| } |