org.apache.lucene.codecs.simpletext.SimpleTextPointsReader Maven / Gradle / Ivy

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Apache Lucene (module: codecs)
There is a newer version: 9.11.1
/*
 * 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.
 */
package org.apache.lucene.codecs.simpletext;


import java.io.IOException;
import java.nio.charset.StandardCharsets;
import java.util.HashMap;
import java.util.Map;

import org.apache.lucene.codecs.PointsReader;
import org.apache.lucene.index.CorruptIndexException;
import org.apache.lucene.index.FieldInfo;
import org.apache.lucene.index.IndexFileNames;
import org.apache.lucene.index.PointValues;
import org.apache.lucene.index.SegmentReadState;
import org.apache.lucene.store.BufferedChecksumIndexInput;
import org.apache.lucene.store.ChecksumIndexInput;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.store.IndexInput;
import org.apache.lucene.util.BytesRef;
import org.apache.lucene.util.BytesRefBuilder;
import org.apache.lucene.util.IOUtils;
import org.apache.lucene.util.StringHelper;

import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.BLOCK_FP;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.BYTES_PER_DIM;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.DOC_COUNT;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.FIELD_COUNT;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.FIELD_FP;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.FIELD_FP_NAME;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.INDEX_COUNT;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.MAX_LEAF_POINTS;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.MAX_VALUE;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.MIN_VALUE;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.NUM_DIMS;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.POINT_COUNT;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.SPLIT_COUNT;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.SPLIT_DIM;
import static org.apache.lucene.codecs.simpletext.SimpleTextPointsWriter.SPLIT_VALUE;

class SimpleTextPointsReader extends PointsReader {

  private final IndexInput dataIn;
  final SegmentReadState readState;
  final Map readers = new HashMap<>();
  final BytesRefBuilder scratch = new BytesRefBuilder();

  public SimpleTextPointsReader(SegmentReadState readState) throws IOException {
    // Initialize readers now:

    // Read index:
    Map fieldToFileOffset = new HashMap<>();

    String indexFileName = IndexFileNames.segmentFileName(readState.segmentInfo.name, readState.segmentSuffix, SimpleTextPointsFormat.POINT_INDEX_EXTENSION);
    try (ChecksumIndexInput in = readState.directory.openChecksumInput(indexFileName, IOContext.DEFAULT)) {
      readLine(in);
      int count = parseInt(FIELD_COUNT);
      for(int i=0;i ent : fieldToFileOffset.entrySet()) {
        readers.put(ent.getKey(), initReader(ent.getValue()));
      }
      success = true;
    } finally {
      if (success == false) {
        IOUtils.closeWhileHandlingException(this);
      }
    }
        
    this.readState = readState;
  }

  private SimpleTextBKDReader initReader(long fp) throws IOException {
    // NOTE: matches what writeIndex does in SimpleTextPointsWriter
    dataIn.seek(fp);
    readLine(dataIn);
    int numDims = parseInt(NUM_DIMS);

    readLine(dataIn);
    int bytesPerDim = parseInt(BYTES_PER_DIM);

    readLine(dataIn);
    int maxPointsInLeafNode = parseInt(MAX_LEAF_POINTS);

    readLine(dataIn);
    int count = parseInt(INDEX_COUNT);

    readLine(dataIn);
    assert startsWith(MIN_VALUE);
    BytesRef minValue = SimpleTextUtil.fromBytesRefString(stripPrefix(MIN_VALUE));
    assert minValue.length == numDims*bytesPerDim;

    readLine(dataIn);
    assert startsWith(MAX_VALUE);
    BytesRef maxValue = SimpleTextUtil.fromBytesRefString(stripPrefix(MAX_VALUE));
    assert maxValue.length == numDims*bytesPerDim;

    readLine(dataIn);
    assert startsWith(POINT_COUNT);
    long pointCount = parseLong(POINT_COUNT);

    readLine(dataIn);
    assert startsWith(DOC_COUNT);
    int docCount = parseInt(DOC_COUNT);
    
    long[] leafBlockFPs = new long[count];
    for(int i=0;i= footerStartPos) {
        // Make sure we landed at precisely the right location:
        if (input.getFilePointer() != footerStartPos) {
          throw new CorruptIndexException("SimpleText failure: footer does not start at expected position current=" + input.getFilePointer() + " vs expected=" + footerStartPos, input);
        }
        SimpleTextUtil.checkFooter(input);
        break;
      }
    }
  }

  @Override
  public long ramBytesUsed() {
    return 0L;
  }

  @Override
  public void close() throws IOException {
    dataIn.close();
  }

  @Override
  public String toString() {
    return "SimpleTextPointsReader(segment=" + readState.segmentInfo.name + " maxDoc=" + readState.segmentInfo.maxDoc() + ")";
  }

}