cvsimport

[beagle.git] / beagled / Lucene.Net / Index / ParallelReader.cs

/*
 * Copyright 2004 The Apache Software Foundation
 * 
 * Licensed 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.
 */

using System;
using Document = Lucene.Net.Documents.Document;
using Field = Lucene.Net.Documents.Field;

namespace Lucene.Net.Index
{
        
        /// <summary>An IndexReader which reads multiple, parallel indexes.  Each index added
        /// must have the same number of documents, but typically each contains
        /// different fields.  Each document contains the union of the fields of all
        /// documents with the same document number.  When searching, matches for a
        /// query term are from the first index added that has the field.
        /// 
        /// <p>This is useful, e.g., with collections that have large fields which
        /// change rarely and small fields that change more frequently.  The smaller
        /// fields may be re-indexed in a new index and both indexes may be searched
        /// together.
        /// 
        /// <p><strong>Warning:</strong> It is up to you to make sure all indexes
        /// are created and modified the same way. For example, if you add
        /// documents to one index, you need to add the same documents in the
        /// same order to the other indexes. <em>Failure to do so will result in
        /// undefined behavior</em>.
        /// </summary>
        public class ParallelReader : IndexReader
        {
                private System.Collections.ArrayList readers = new System.Collections.ArrayList();
                private System.Collections.SortedList fieldToReader = new System.Collections.SortedList();
                private System.Collections.ArrayList storedFieldReaders = new System.Collections.ArrayList();
                
                private int maxDoc;
                private int numDocs;
                private bool hasDeletions;
                
                /// <summary>Construct a ParallelReader. </summary>
                public ParallelReader() : base(null)
                {
                }
                
                /// <summary>Add an IndexReader. </summary>
                public virtual void  Add(IndexReader reader)
                {
                        Add(reader, false);
                }
                
                /// <summary>Add an IndexReader whose stored fields will not be returned.  This can
                /// accellerate search when stored fields are only needed from a subset of
                /// the IndexReaders.
                /// 
                /// </summary>
                /// <throws>  IllegalArgumentException if not all indexes contain the same number  </throws>
                /// <summary>     of documents
                /// </summary>
                /// <throws>  IllegalArgumentException if not all indexes have the same value  </throws>
                /// <summary>     of {@link IndexReader#MaxDoc()}
                /// </summary>
                public virtual void  Add(IndexReader reader, bool ignoreStoredFields)
                {
                        
                        if (readers.Count == 0)
                        {
                                this.maxDoc = reader.MaxDoc();
                                this.numDocs = reader.NumDocs();
                                this.hasDeletions = reader.HasDeletions();
                        }
                        
                        if (reader.MaxDoc() != maxDoc)
                        // check compatibility
                                throw new System.ArgumentException("All readers must have same maxDoc: " + maxDoc + "!=" + reader.MaxDoc());
                        if (reader.NumDocs() != numDocs)
                                throw new System.ArgumentException("All readers must have same numDocs: " + numDocs + "!=" + reader.NumDocs());
                        
                        System.Collections.IEnumerator i = reader.GetFieldNames(IndexReader.FieldOption.ALL).GetEnumerator();
                        while (i.MoveNext())
                        {
                System.Collections.DictionaryEntry fi = (System.Collections.DictionaryEntry) i.Current;

                                // update fieldToReader map
                                System.String field = fi.Key.ToString();
                                if (fieldToReader[field] == null)
                                        fieldToReader[field] = reader;
                        }
                        
                        if (!ignoreStoredFields)
                                storedFieldReaders.Add(reader); // add to storedFieldReaders
                        readers.Add(reader);
                }
                
                public override int NumDocs()
                {
                        return numDocs;
                }
                
                public override int MaxDoc()
                {
                        return maxDoc;
                }
                
                public override bool HasDeletions()
                {
                        return hasDeletions;
                }
                
                // check first reader
                public override bool IsDeleted(int n)
                {
                        if (readers.Count > 0)
                                return ((IndexReader) readers[0]).IsDeleted(n);
                        return false;
                }
                
                // delete in all readers
                protected internal override void  DoDelete(int n)
                {
                        for (int i = 0; i < readers.Count; i++)
                        {
                                ((IndexReader) readers[i]).DoDelete(n);
                        }
                        hasDeletions = true;
                }
                
                // undeleteAll in all readers
                protected internal override void  DoUndeleteAll()
                {
                        for (int i = 0; i < readers.Count; i++)
                        {
                                ((IndexReader) readers[i]).DoUndeleteAll();
                        }
                        hasDeletions = false;
                }
                
                // append fields from storedFieldReaders
                public override Document Document(int n)
                {
                        Document result = new Document();
                        for (int i = 0; i < storedFieldReaders.Count; i++)
                        {
                                IndexReader reader = (IndexReader) storedFieldReaders[i];
                foreach(Field field in reader.Document(n).Fields())
                                {
                                        result.Add(field);
                                }
                        }
                        return result;
                }
                
                // get all vectors
                public override TermFreqVector[] GetTermFreqVectors(int n)
                {
                        System.Collections.ArrayList results = new System.Collections.ArrayList();
                        System.Collections.IEnumerator i = new System.Collections.Hashtable(fieldToReader).GetEnumerator();
                        while (i.MoveNext())
                        {
                                System.Collections.DictionaryEntry e = (System.Collections.DictionaryEntry) i.Current;
                                IndexReader reader = (IndexReader) e.Key;
                                System.String field = (System.String) e.Value;
                                TermFreqVector vector = reader.GetTermFreqVector(n, field);
                                if (vector != null)
                                        results.Add(vector);
                        }
                        return (TermFreqVector[]) (results.ToArray(typeof(TermFreqVector)));
                }
                
                public override TermFreqVector GetTermFreqVector(int n, System.String field)
                {
                        return ((IndexReader) fieldToReader[field]).GetTermFreqVector(n, field);
                }
                
                public override bool HasNorms(System.String field)
                {
                        return ((IndexReader) fieldToReader[field]).HasNorms(field);
                }
                
                public override byte[] Norms(System.String field)
                {
                        return ((IndexReader) fieldToReader[field]).Norms(field);
                }
                
                public override void  Norms(System.String field, byte[] result, int offset)
                {
                        ((IndexReader) fieldToReader[field]).Norms(field, result, offset);
                }
                
                protected internal override void  DoSetNorm(int n, System.String field, byte value_Renamed)
                {
                        ((IndexReader) fieldToReader[field]).DoSetNorm(n, field, value_Renamed);
                }
                
                public override TermEnum Terms()
                {
                        return new ParallelTermEnum(this);
                }
                
                public override TermEnum Terms(Term term)
                {
                        return new ParallelTermEnum(this, term);
                }
                
                public override int DocFreq(Term term)
                {
                        return ((IndexReader) fieldToReader[term.Field()]).DocFreq(term);
                }
                
                public override TermDocs TermDocs(Term term)
                {
                        return new ParallelTermDocs(this, term);
                }
                
                public override TermDocs TermDocs()
                {
                        return new ParallelTermDocs(this);
                }
                
                public override TermPositions TermPositions(Term term)
                {
                        return new ParallelTermPositions(this, term);
                }
                
                public override TermPositions TermPositions()
                {
                        return new ParallelTermPositions(this);
                }
                
                protected internal override void  DoCommit()
                {
                        for (int i = 0; i < readers.Count; i++)
                                ((IndexReader) readers[i]).Commit();
                }
                
                protected internal override void  DoClose()
                {
                        lock (this)
                        {
                                for (int i = 0; i < readers.Count; i++)
                                        ((IndexReader) readers[i]).Close();
                        }
                }
                
                public override System.Collections.ICollection GetFieldNames()
                {
            System.Collections.Hashtable result = new System.Collections.Hashtable(fieldToReader.Count);
            System.Collections.ICollection items = fieldToReader.Keys;
            foreach (object item in items)
            {
                result.Add(item, item);
            }
            return result;
                }
                
                public override System.Collections.ICollection GetFieldNames(bool indexed)
                {
                        System.Collections.Hashtable fieldSet = new System.Collections.Hashtable();
                        for (int i = 0; i < readers.Count; i++)
                        {
                                IndexReader reader = ((IndexReader) readers[i]);
                                System.Collections.ICollection names = reader.GetFieldNames(indexed);
                for (System.Collections.IEnumerator iterator = names.GetEnumerator(); iterator.MoveNext(); )
                {
                    System.Collections.DictionaryEntry fi = (System.Collections.DictionaryEntry) iterator.Current;
                    System.String s = fi.Key.ToString();
                    if (fieldSet.ContainsKey(s) == false)
                    {
                        fieldSet.Add(s, s);
                    }
                }
                        }
                        return fieldSet;
                }
                
                public override System.Collections.ICollection GetIndexedFieldNames(Field.TermVector tvSpec)
                {
                        System.Collections.Hashtable fieldSet = new System.Collections.Hashtable();
                        for (int i = 0; i < readers.Count; i++)
                        {
                                IndexReader reader = ((IndexReader) readers[i]);
                                System.Collections.ICollection names = reader.GetIndexedFieldNames(tvSpec);
                for (System.Collections.IEnumerator iterator = names.GetEnumerator(); iterator.MoveNext(); )
                {
                    System.Collections.DictionaryEntry fi = (System.Collections.DictionaryEntry) iterator.Current;
                    System.String s = fi.Key.ToString();
                    if (fieldSet.ContainsKey(s) == false)
                    {
                        fieldSet.Add(s, s);
                    }
                }
            }
                        return fieldSet;
                }
                
                public override System.Collections.ICollection GetFieldNames(IndexReader.FieldOption fieldNames)
                {
            System.Collections.Hashtable fieldSet = new System.Collections.Hashtable();
            for (int i = 0; i < readers.Count; i++)
            {
                IndexReader reader = ((IndexReader) readers[i]);
                System.Collections.ICollection names = reader.GetFieldNames(fieldNames);
                for (System.Collections.IEnumerator iterator = names.GetEnumerator(); iterator.MoveNext(); )
                {
                    System.Collections.DictionaryEntry fi = (System.Collections.DictionaryEntry) iterator.Current;
                    System.String s = fi.Key.ToString();
                    if (fieldSet.ContainsKey(s) == false)
                    {
                        fieldSet.Add(s, s);
                    }
                }
            }
            return fieldSet;
                }
                
                private class ParallelTermEnum : TermEnum
                {
                        private void  InitBlock(ParallelReader enclosingInstance)
                        {
                                this.enclosingInstance = enclosingInstance;
                        }
                        private ParallelReader enclosingInstance;
                        public ParallelReader Enclosing_Instance
                        {
                                get
                                {
                                        return enclosingInstance;
                                }
                                
                        }
                        private System.String field;
                        private TermEnum termEnum;
                        
                        public ParallelTermEnum(ParallelReader enclosingInstance)
                        {
                                InitBlock(enclosingInstance);
                                field = ((System.String) Enclosing_Instance.fieldToReader.GetKey(0));
                                if (field != null)
                                        termEnum = ((IndexReader) Enclosing_Instance.fieldToReader[field]).Terms();
                        }
                        
                        public ParallelTermEnum(ParallelReader enclosingInstance, Term term)
                        {
                                InitBlock(enclosingInstance);
                                field = term.Field();
                                termEnum = ((IndexReader) Enclosing_Instance.fieldToReader[field]).Terms(term);
                        }
                        
                        public override bool Next()
                        {
                                if (field == null)
                                        return false;
                                
                                bool next = termEnum.Next();
                                
                                // still within field?
                                if (next && (System.Object) termEnum.Term().Field() == (System.Object) field)
                                        return true; // yes, keep going
                                
                                termEnum.Close(); // close old termEnum
                                
                                // find the next field, if any
                                field = ((System.String) SupportClass.TailMap(Enclosing_Instance.fieldToReader, field).GetKey(0));
                                if (field != null)
                                {
                                        termEnum = ((IndexReader) Enclosing_Instance.fieldToReader[field]).Terms();
                                        return true;
                                }
                                
                                return false; // no more fields
                        }
                        
                        public override Term Term()
                        {
                                return termEnum.Term();
                        }
                        public override int DocFreq()
                        {
                                return termEnum.DocFreq();
                        }
                        public override void  Close()
                        {
                                termEnum.Close();
                        }
                }
                
                // wrap a TermDocs in order to support seek(Term)
                private class ParallelTermDocs : TermDocs
                {
                        private void  InitBlock(ParallelReader enclosingInstance)
                        {
                                this.enclosingInstance = enclosingInstance;
                        }
                        private ParallelReader enclosingInstance;
                        public ParallelReader Enclosing_Instance
                        {
                                get
                                {
                                        return enclosingInstance;
                                }
                                
                        }
                        protected internal TermDocs termDocs;
                        
                        public ParallelTermDocs(ParallelReader enclosingInstance)
                        {
                                InitBlock(enclosingInstance);
                        }
                        public ParallelTermDocs(ParallelReader enclosingInstance, Term term)
                        {
                                InitBlock(enclosingInstance);
                                Seek(term);
                        }
                        
                        public virtual int Doc()
                        {
                                return termDocs.Doc();
                        }
                        public virtual int Freq()
                        {
                                return termDocs.Freq();
                        }
                        
                        public virtual void  Seek(Term term)
                        {
                                termDocs = ((IndexReader) Enclosing_Instance.fieldToReader[term.Field()]).TermDocs(term);
                        }
                        
                        public virtual void  Seek(TermEnum termEnum)
                        {
                                Seek(termEnum.Term());
                        }
                        
                        public virtual bool Next()
                        {
                                return termDocs.Next();
                        }
                        
                        public virtual int Read(int[] docs, int[] freqs)
                        {
                                return termDocs.Read(docs, freqs);
                        }
                        
                        public virtual bool SkipTo(int target)
                        {
                                return termDocs.SkipTo(target);
                        }
                        
                        public virtual void  Close()
                        {
                                termDocs.Close();
                        }
                }
                
                private class ParallelTermPositions : ParallelTermDocs, TermPositions
                {
                        private void  InitBlock(ParallelReader enclosingInstance)
                        {
                                this.enclosingInstance = enclosingInstance;
                        }
                        private ParallelReader enclosingInstance;
                        public new ParallelReader Enclosing_Instance
                        {
                                get
                                {
                                        return enclosingInstance;
                                }
                                
                        }
                        
                        public ParallelTermPositions(ParallelReader enclosingInstance) : base(enclosingInstance)
                        {
                                InitBlock(enclosingInstance);
                        }
                        public ParallelTermPositions(ParallelReader enclosingInstance, Term term) : base(enclosingInstance)
                        {
                                InitBlock(enclosingInstance);
                                Seek(term);
                        }
                        
                        public override void  Seek(Term term)
                        {
                                termDocs = ((IndexReader) Enclosing_Instance.fieldToReader[term.Field()]).TermPositions(term);
                        }
                        
                        public virtual int NextPosition()
                        {
                                return ((TermPositions) termDocs).NextPosition();
                        }
                }
        }
}