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.db.rows;
  
  import org.apache.cassandra.schema.TableMetadata;
  import org.apache.cassandra.db.DecoratedKey;
  import org.apache.cassandra.db.RegularAndStaticColumns;
  import org.apache.cassandra.utils.CloseableIterator;
  
  /**
   * A common interface for Row and Unfiltered, that permits sharing of the (majority) common
   * methods and functionality
   */
  public interface BaseRowIterator<U extends Unfiltered> extends CloseableIterator<U>
  {
      /**
       * The metadata for the table this iterator on.
       */
      public TableMetadata metadata();
  
      /**
       * Whether or not the rows returned by this iterator are in reversed
       * clustering order.
       */
      public boolean isReverseOrder();
  
      /**
       * A subset of the columns for the (static and regular) rows returned by this iterator.
       * Every row returned by this iterator must guarantee that it has only those columns.
       */
      public RegularAndStaticColumns columns();
  
      /**
       * The partition key of the partition this in an iterator over.
       */
      public DecoratedKey partitionKey();
  
      /**
       * The static part corresponding to this partition (this can be an empty
       * row but cannot be {@code null}).
       */
      public Row staticRow();
  
      /**
       * Returns whether the provided iterator has no data.
       */
      public boolean isEmpty();
  }
  