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 * 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
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 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.lucene.index;


import java.io.IOException;

import static org.apache.lucene.index.FilterLeafReader.FilterFields;
import static org.apache.lucene.index.FilterLeafReader.FilterTerms;
import static org.apache.lucene.index.FilterLeafReader.FilterTermsEnum;

A Fields implementation that merges multiple Fields into one, and maps around deleted documents. This is used for merging. @lucene.internal
/** A {@link Fields} implementation that merges multiple * Fields into one, and maps around deleted documents. * This is used for merging. * @lucene.internal */
public class MappedMultiFields extends FilterFields { final MergeState mergeState;
Create a new MappedMultiFields for merging, based on the supplied mergestate and merged view of terms.
/** Create a new MappedMultiFields for merging, based on the supplied * mergestate and merged view of terms. */
public MappedMultiFields(MergeState mergeState, MultiFields multiFields) { super(multiFields); this.mergeState = mergeState; } @Override public Terms terms(String field) throws IOException { MultiTerms terms = (MultiTerms) in.terms(field); if (terms == null) { return null; } else { return new MappedMultiTerms(field, mergeState, terms); } } private static class MappedMultiTerms extends FilterTerms { final MergeState mergeState; final String field; public MappedMultiTerms(String field, MergeState mergeState, MultiTerms multiTerms) { super(multiTerms); this.field = field; this.mergeState = mergeState; } @Override public TermsEnum iterator() throws IOException { TermsEnum iterator = in.iterator(); if (iterator == TermsEnum.EMPTY) { // LUCENE-6826 return TermsEnum.EMPTY; } else { return new MappedMultiTermsEnum(field, mergeState, (MultiTermsEnum) iterator); } } @Override public long size() throws IOException { throw new UnsupportedOperationException(); } @Override public long getSumTotalTermFreq() throws IOException { throw new UnsupportedOperationException(); } @Override public long getSumDocFreq() throws IOException { throw new UnsupportedOperationException(); } @Override public int getDocCount() throws IOException { throw new UnsupportedOperationException(); } } private static class MappedMultiTermsEnum extends FilterTermsEnum { final MergeState mergeState; final String field; public MappedMultiTermsEnum(String field, MergeState mergeState, MultiTermsEnum multiTermsEnum) { super(multiTermsEnum); this.field = field; this.mergeState = mergeState; } @Override public int docFreq() throws IOException { throw new UnsupportedOperationException(); } @Override public long totalTermFreq() throws IOException { throw new UnsupportedOperationException(); } @Override public PostingsEnum postings(PostingsEnum reuse, int flags) throws IOException { MappingMultiPostingsEnum mappingDocsAndPositionsEnum; if (reuse instanceof MappingMultiPostingsEnum) { MappingMultiPostingsEnum postings = (MappingMultiPostingsEnum) reuse; if (postings.field.equals(this.field)) { mappingDocsAndPositionsEnum = postings; } else { mappingDocsAndPositionsEnum = new MappingMultiPostingsEnum(field, mergeState); } } else { mappingDocsAndPositionsEnum = new MappingMultiPostingsEnum(field, mergeState); } MultiPostingsEnum docsAndPositionsEnum = (MultiPostingsEnum) in.postings(mappingDocsAndPositionsEnum.multiDocsAndPositionsEnum, flags); mappingDocsAndPositionsEnum.reset(docsAndPositionsEnum); return mappingDocsAndPositionsEnum; } } }