/* * * 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.filter; import java.nio.ByteBuffer; import org.apache.cassandra.db.Column; import org.apache.cassandra.db.ColumnFamily; import org.apache.cassandra.db.DeletionInfo; import org.apache.cassandra.db.marshal.CompositeType; import org.apache.cassandra.utils.ByteBufferUtil; public class ColumnCounter { protected int live; protected int ignored; protected final long timestamp; public ColumnCounter(long timestamp) { this.timestamp = timestamp; } public void count(Column column, DeletionInfo.InOrderTester tester) { if (!isLive(column, tester, timestamp)) ignored++; else live++; } protected static boolean isLive(Column column, DeletionInfo.InOrderTester tester, long timestamp) { return column.isLive(timestamp) && (!tester.isDeleted(column)); } public int live() { return live; } public int ignored() { return ignored; } public ColumnCounter countAll(ColumnFamily container) { if (container == null) return this; DeletionInfo.InOrderTester tester = container.inOrderDeletionTester(); for (Column c : container) count(c, tester); return this; } public static class GroupByPrefix extends ColumnCounter { private final CompositeType type; private final int toGroup; private ByteBuffer[] last; /** * A column counter that count only 1 for all the columns sharing a * given prefix of the key. * * @param type the type of the column name. This can be null if {@code * toGroup} is 0, otherwise it should be a composite. * @param toGroup the number of composite components on which to group * column. If 0, all columns are grouped, otherwise we group * those for which the {@code toGroup} first component are equals. */ public GroupByPrefix(long timestamp, CompositeType type, int toGroup) { super(timestamp); this.type = type; this.toGroup = toGroup; assert toGroup == 0 || type != null; } public void count(Column column, DeletionInfo.InOrderTester tester) { if (!isLive(column, tester, timestamp)) { ignored++; return; } if (toGroup == 0) { live = 1; return; } ByteBuffer[] current = type.split(column.name()); assert current.length >= toGroup; if (last != null) { boolean isSameGroup = true; for (int i = 0; i < toGroup; i++) { if (ByteBufferUtil.compareUnsigned(last[i], current[i]) != 0) { isSameGroup = false; break; } } if (isSameGroup) return; } live++; last = current; } } }