content: /*
   * 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.cassandra.service.accord;
  
  import java.util.Arrays;
  import java.util.HashSet;
  import java.util.Set;
  
  import accord.utils.RandomSource;
  import org.apache.cassandra.db.ColumnFamilyStore;
  import org.apache.cassandra.db.SerializationHeader;
  import org.apache.cassandra.db.rows.EncodingStats;
  import org.apache.cassandra.io.sstable.Descriptor;
  import org.apache.cassandra.io.sstable.SSTableTxnWriter;
  import org.apache.cassandra.service.accord.serializers.Version;
  
  /**
   * Nemesis compactor: a compactor that will distribute your keys over a large(r) number of SSTables.
   *
   * For testing purposes only.
   */
  public class NemesisAccordSegmentCompactor<V> extends AbstractAccordSegmentCompactor<V>
  {
      private final RandomSource randomSource;
      private final SSTableTxnWriter[] writers;
      private final Set<SSTableTxnWriter> written = new HashSet<>();
  
      public NemesisAccordSegmentCompactor(Version userVersion, ColumnFamilyStore cfs, RandomSource randomSource)
      {
          super(userVersion, cfs);
          this.randomSource = randomSource;
          this.writers = new SSTableTxnWriter[randomSource.nextInt(2, 10)];
      }
  
      @Override
      boolean considerWritingKey()
      {
          if (written.size() == writers.length - 1)
              return false;
          return randomSource.nextBoolean();
      }
  
      @Override
      void switchPartitions()
      {
          written.clear();
      }
  
      @Override
      void initializeWriter(int estimatedKeyCount)
      {
          for (int i = 0; i < writers.length; i++)
          {
              Descriptor descriptor = cfs.newSSTableDescriptor(cfs.getDirectories().getDirectoryForNewSSTables());
              SerializationHeader header = new SerializationHeader(true, cfs.metadata(), cfs.metadata().regularAndStaticColumns(), EncodingStats.NO_STATS);
              writers[i] = SSTableTxnWriter.create(cfs, descriptor, 0, 0, null, false, header);
          }
      }
  
      @Override
      SSTableTxnWriter writer()
      {
          for (int i = 0; i < 10_000; i++)
          {
              SSTableTxnWriter writer = writers[randomSource.nextInt(writers.length)];
              if (written.add(writer))
                  return writer;
          }
          throw new IllegalStateException(String.format("Could not pick an sstable from %s. Written: %s", Arrays.asList(writers), written));
      }
  
      @Override
      void finishAndAddWriter()
      {
          for (SSTableTxnWriter writer : writers)
          {
              cfs.addSSTables(writer.finish(true));
              writer.close();
          }
          Arrays.fill(writers, null);
      }
  
      @Override
      Throwable cleanupWriter(Throwable t)
      {
          for (SSTableTxnWriter writer : writers)
              t = writer.abort(t);
          return t;
      }
  }
  