| /* |
| * 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.pager; |
| |
| import org.apache.cassandra.config.CFMetaData; |
| import org.apache.cassandra.db.*; |
| import org.apache.cassandra.db.filter.*; |
| import org.apache.cassandra.db.partitions.*; |
| import org.apache.cassandra.exceptions.RequestExecutionException; |
| import org.apache.cassandra.exceptions.RequestValidationException; |
| import org.apache.cassandra.service.ClientState; |
| import org.apache.cassandra.transport.Server; |
| |
| /** |
| * Static utility methods for paging. |
| */ |
| public class QueryPagers |
| { |
| private QueryPagers() {}; |
| |
| /** |
| * Convenience method that count (live) cells/rows for a given slice of a row, but page underneath. |
| */ |
| public static int countPaged(CFMetaData metadata, |
| DecoratedKey key, |
| ColumnFilter columnFilter, |
| ClusteringIndexFilter filter, |
| DataLimits limits, |
| ConsistencyLevel consistencyLevel, |
| ClientState state, |
| final int pageSize, |
| int nowInSec, |
| boolean isForThrift) throws RequestValidationException, RequestExecutionException |
| { |
| SinglePartitionReadCommand command = SinglePartitionReadCommand.create(isForThrift, metadata, nowInSec, columnFilter, RowFilter.NONE, limits, key, filter); |
| final SinglePartitionPager pager = new SinglePartitionPager(command, null, Server.CURRENT_VERSION); |
| |
| int count = 0; |
| while (!pager.isExhausted()) |
| { |
| try (PartitionIterator iter = pager.fetchPage(pageSize, consistencyLevel, state)) |
| { |
| DataLimits.Counter counter = limits.newCounter(nowInSec, true, command.selectsFullPartition(), metadata.enforceStrictLiveness()); |
| PartitionIterators.consume(counter.applyTo(iter)); |
| count += counter.counted(); |
| } |
| } |
| return count; |
| } |
| } |