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.io.sstable.format.bti;
  
  import java.io.IOException;
  
  import org.apache.cassandra.db.DecoratedKey;
  import org.apache.cassandra.db.Slice;
  import org.apache.cassandra.db.Slices;
  import org.apache.cassandra.db.filter.ColumnFilter;
  import org.apache.cassandra.io.sstable.AbstractRowIndexEntry;
  import org.apache.cassandra.io.sstable.AbstractSSTableIterator;
  import org.apache.cassandra.io.sstable.format.Version;
  import org.apache.cassandra.io.sstable.format.bti.RowIndexReader.IndexInfo;
  import org.apache.cassandra.io.util.FileDataInput;
  import org.apache.cassandra.io.util.FileHandle;
  
  /**
   *  Unfiltered row iterator over a BTI SSTable.
   */
  class SSTableIterator extends AbstractSSTableIterator<AbstractRowIndexEntry>
  {
      /**
       * The index of the slice being processed.
       */
      private int slice;
  
      public SSTableIterator(BtiTableReader sstable,
                             FileDataInput file,
                             DecoratedKey key,
                             AbstractRowIndexEntry indexEntry,
                             Slices slices,
                             ColumnFilter columns,
                             FileHandle ifile)
      {
          super(sstable, file, key, indexEntry, slices, columns, ifile);
      }
  
      protected Reader createReaderInternal(AbstractRowIndexEntry indexEntry, FileDataInput file, boolean shouldCloseFile, Version version)
      {
          if (indexEntry.isIndexed())
              return new ForwardIndexedReader(indexEntry, file, shouldCloseFile, version);
          else
              return new ForwardReader(file, shouldCloseFile);
      }
  
      protected int nextSliceIndex()
      {
          int next = slice;
          slice++;
          return next;
      }
  
      protected boolean hasMoreSlices()
      {
          return slice < slices.size();
      }
  
      public boolean isReverseOrder()
      {
          return false;
      }
  
      private class ForwardIndexedReader extends ForwardReader
      {
          private final RowIndexReader indexReader;
          private final long basePosition;
          private final Version version;
  
          private ForwardIndexedReader(AbstractRowIndexEntry indexEntry, FileDataInput file, boolean shouldCloseFile, Version version)
          {
              super(file, shouldCloseFile);
              basePosition = indexEntry.position;
              this.version = version;
              indexReader = new RowIndexReader(ifile, (TrieIndexEntry) indexEntry, version);
          }
  
          @Override
          public void close() throws IOException
          {
              indexReader.close();
              super.close();
          }
  
          @Override
          public void setForSlice(Slice slice) throws IOException
          {
              super.setForSlice(slice);
              IndexInfo indexInfo = indexReader.separatorFloor(metadata.comparator.asByteComparable(slice.start()));
              assert indexInfo != null;
              long position = basePosition + indexInfo.offset;
              if (file == null || position > file.getFilePointer())
              {
                  openMarker = indexInfo.openDeletion;
                  seekToPosition(position);
              }
              // Otherwise we are already in the relevant index block, there is no point to go back to its beginning.
          }
      }
  }
  