| /* |
| * 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.partitions; |
| |
| import java.util.NavigableSet; |
| |
| import javax.annotation.Nullable; |
| |
| import org.apache.cassandra.schema.TableMetadata; |
| import org.apache.cassandra.db.Slices; |
| import org.apache.cassandra.db.*; |
| import org.apache.cassandra.db.rows.*; |
| import org.apache.cassandra.db.filter.ColumnFilter; |
| |
| /** |
| * In-memory representation of a Partition. |
| * |
| * Note that most of the storage engine works through iterators (UnfilteredPartitionIterator) to |
| * avoid "materializing" a full partition/query response in memory as much as possible, |
| * and so Partition objects should be use as sparingly as possible. There is a couple |
| * of cases where we do need to represent partition in-memory (memtables and row cache). |
| */ |
| public interface Partition |
| { |
| public TableMetadata metadata(); |
| public DecoratedKey partitionKey(); |
| public DeletionTime partitionLevelDeletion(); |
| |
| public RegularAndStaticColumns columns(); |
| |
| public EncodingStats stats(); |
| |
| /** |
| * Whether the partition object has no informations at all, including any deletion informations. |
| */ |
| public boolean isEmpty(); |
| |
| /** |
| * Returns the row corresponding to the provided clustering, or null if there is not such row. |
| * |
| * @param clustering clustering key to search |
| * @return row corresponding to the clustering, it's either null or non-empty row. |
| */ |
| public @Nullable Row getRow(Clustering<?> clustering); |
| |
| /** |
| * Returns an UnfilteredRowIterator over all the rows/RT contained by this partition. |
| */ |
| public UnfilteredRowIterator unfilteredIterator(); |
| |
| /** |
| * Returns an UnfilteredRowIterator over the rows/RT contained by this partition |
| * selected by the provided slices. |
| */ |
| public UnfilteredRowIterator unfilteredIterator(ColumnFilter columns, Slices slices, boolean reversed); |
| |
| /** |
| * Returns an UnfilteredRowIterator over the rows/RT contained by this partition |
| * selected by the provided clusterings. |
| */ |
| public UnfilteredRowIterator unfilteredIterator(ColumnFilter columns, NavigableSet<Clustering<?>> clusteringsInQueryOrder, boolean reversed); |
| } |