/*
 * 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;

import java.io.IOException;
import java.util.Collection;
import org.apache.lucene.index.SegmentCommitInfo;
import org.apache.lucene.store.Directory;
import org.apache.lucene.store.IOContext;
import org.apache.lucene.util.Bits;

/**
 * Format for live/deleted documents
 *
 * @lucene.experimental
 */
public abstract class LiveDocsFormat {

  /** Sole constructor. (For invocation by subclass constructors, typically implicit.) */
  protected LiveDocsFormat() {}

  /** Read live docs bits. */
  public abstract Bits readLiveDocs(Directory dir, SegmentCommitInfo info, IOContext context)
      throws IOException;

  /**
   * Persist live docs bits. Use {@link SegmentCommitInfo#getNextDelGen} to determine the generation
   * of the deletes file you should write to.
   */
  public abstract void writeLiveDocs(
      Bits bits, Directory dir, SegmentCommitInfo info, int newDelCount, IOContext context)
      throws IOException;

  /** Records all files in use by this {@link SegmentCommitInfo} into the files argument. */
  public abstract void files(SegmentCommitInfo info, Collection<String> files) throws IOException;
}
