content: package org.apache.lucene.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.
   */
  
  import java.io.IOException;
  
  import org.apache.lucene.util.AttributeSource;
  import org.apache.lucene.analysis.tokenattributes.OffsetAttribute;
  import org.apache.lucene.analysis.tokenattributes.CharTermAttribute;
  
  /** This is a DocFieldConsumer that inverts each field,
   *  separately, from a Document, and accepts a
   *  InvertedTermsConsumer to process those terms. */
  
  final class DocInverterPerThread extends DocFieldConsumerPerThread {
    final DocInverter docInverter;
    final InvertedDocConsumerPerThread consumer;
    final InvertedDocEndConsumerPerThread endConsumer;
    final SingleTokenAttributeSource singleToken = new SingleTokenAttributeSource();
    
    static class SingleTokenAttributeSource extends AttributeSource {
      final CharTermAttribute termAttribute;
      final OffsetAttribute offsetAttribute;
      
      private SingleTokenAttributeSource() {
        termAttribute = addAttribute(CharTermAttribute.class);
        offsetAttribute = addAttribute(OffsetAttribute.class);
      }
      
      public void reinit(String stringValue, int startOffset,  int endOffset) {
        termAttribute.setEmpty().append(stringValue);
        offsetAttribute.setOffset(startOffset, endOffset);
      }
    }
    
    final DocumentsWriter.DocState docState;
  
    final FieldInvertState fieldState = new FieldInvertState();
  
    // Used to read a string value for a field
    final ReusableStringReader stringReader = new ReusableStringReader();
  
    public DocInverterPerThread(DocFieldProcessorPerThread docFieldProcessorPerThread, DocInverter docInverter) {
      this.docInverter = docInverter;
      docState = docFieldProcessorPerThread.docState;
      consumer = docInverter.consumer.addThread(this);
      endConsumer = docInverter.endConsumer.addThread(this);
    }
  
    @Override
    public void startDocument() throws IOException {
      consumer.startDocument();
      endConsumer.startDocument();
    }
  
    @Override
    public DocumentsWriter.DocWriter finishDocument() throws IOException {
      // TODO: allow endConsumer.finishDocument to also return
      // a DocWriter
      endConsumer.finishDocument();
      return consumer.finishDocument();
    }
  
    @Override
    void abort() {
      try {
        consumer.abort();
      } finally {
        endConsumer.abort();
      }
    }
  
    @Override
    public DocFieldConsumerPerField addField(FieldInfo fi) {
      return new DocInverterPerField(this, fi);
    }
  }
  