http://lucene.apache.org/lucene-parent/lucene-core: Apache Lucene Java Core (The Apache Software Foundation) 
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 * 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
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 *
 *     http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.lucene.codecs;


import java.io.IOException;

import org.apache.lucene.index.SegmentInfo;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IOContext;


Expert: Controls the format of the SegmentInfo (segment metadata file). 
See Also:
@lucene.experimental
/**
 * Expert: Controls the format of the 
 * {@link SegmentInfo} (segment metadata file).
 * @see SegmentInfo
 * @lucene.experimental
 */
public abstract class SegmentInfoFormat {
  
Sole constructor. (For invocation by subclass 
 constructors, typically implicit.) 
/** Sole constructor. (For invocation by subclass 
   *  constructors, typically implicit.) */
  protected SegmentInfoFormat() {
  }

  
Read SegmentInfo data from a directory. 
Params:
  • directory – directory to read from
  • segmentName – name of the segment to read
  • segmentID – expected identifier for the segment
Throws:
Returns:infos instance to be populated with data
/**
   * Read {@link SegmentInfo} data from a directory.
   * @param directory directory to read from
   * @param segmentName name of the segment to read
   * @param segmentID expected identifier for the segment
   * @return infos instance to be populated with data
   * @throws IOException If an I/O error occurs
   */
  public abstract SegmentInfo read(Directory directory, String segmentName, byte segmentID[], IOContext context) throws IOException;

  
Write SegmentInfo data. The codec must add its SegmentInfo filename(s) to info before doing i/o. 
Throws:
/**
   * Write {@link SegmentInfo} data.
   * The codec must add its SegmentInfo filename(s) to {@code info} before doing i/o. 
   * @throws IOException If an I/O error occurs
   */
  public abstract void write(Directory dir, SegmentInfo info, IOContext ioContext) throws IOException;
}