| /* |
| * 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.repair.asymmetric; |
| |
| import java.util.Collection; |
| import java.util.HashSet; |
| import java.util.Map; |
| import java.util.Set; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| import com.google.common.collect.Sets; |
| |
| import org.slf4j.Logger; |
| import org.slf4j.LoggerFactory; |
| |
| import org.apache.cassandra.dht.Range; |
| import org.apache.cassandra.dht.RingPosition; |
| import org.apache.cassandra.dht.Token; |
| |
| public class RangeDenormalizer |
| { |
| private static final Logger logger = LoggerFactory.getLogger(RangeDenormalizer.class); |
| |
| /** |
| * "Denormalizes" (kind of the opposite of what Range.normalize does) the ranges in the keys of {{incoming}} |
| * |
| * It makes sure that if there is an intersection between {{range}} and some of the ranges in {{incoming.keySet()}} |
| * we know that all intersections are keys in the updated {{incoming}} |
| */ |
| public static Set<Range<Token>> denormalize(Range<Token> range, RangeMap<StreamFromOptions> incoming) |
| { |
| logger.trace("Denormalizing range={} incoming={}", range, incoming); |
| Set<Map.Entry<Range<Token>, StreamFromOptions>> existingOverlappingRanges = incoming.removeIntersecting(range); |
| |
| Set<Range<Token>> intersections = intersection(existingOverlappingRanges, range); |
| Set<Range<Token>> newExisting = Sets.union(subtractFromAllRanges(existingOverlappingRanges, range), intersections); |
| Set<Range<Token>> newInput = Sets.union(subtractAll(existingOverlappingRanges, range), intersections); |
| for (Range<Token> r : newExisting) |
| { |
| for (Map.Entry<Range<Token>, StreamFromOptions> entry : existingOverlappingRanges) |
| { |
| if (r.intersects(entry.getKey())) |
| incoming.put(r, entry.getValue().copy(r)); |
| } |
| } |
| logger.trace("denormalized {} to {}", range, newInput); |
| logger.trace("denormalized incoming to {}", incoming); |
| return newInput; |
| } |
| |
| /** |
| * Subtract the given range from all the input ranges. |
| * |
| * for example: |
| * ranges = [(0, 10], (20, 30]] |
| * and range = (8, 22] |
| * |
| * the result should be [(0, 8], (22, 30]] |
| * |
| */ |
| @VisibleForTesting |
| static Set<Range<Token>> subtractFromAllRanges(Collection<Map.Entry<Range<Token>, StreamFromOptions>> ranges, Range<Token> range) |
| { |
| Set<Range<Token>> result = new HashSet<>(); |
| for (Map.Entry<Range<Token>, ?> r : ranges) |
| result.addAll(r.getKey().subtract(range)); // subtract can return two ranges if we remove the middle part |
| return result; |
| } |
| |
| /** |
| * Returns all intersections between the ranges in ranges and the given range |
| */ |
| private static Set<Range<Token>> intersection(Set<Map.Entry<Range<Token>, StreamFromOptions>> ranges, Range<Token> range) |
| { |
| Set<Range<Token>> result = new HashSet<>(); |
| for (Map.Entry<Range<Token>, StreamFromOptions> r : ranges) |
| result.addAll(range.intersectionWith(r.getKey())); |
| return result; |
| } |
| |
| /** |
| * copied from Range - need to iterate over the map entries |
| */ |
| public static Set<Range<Token>> subtractAll(Collection<Map.Entry<Range<Token>, StreamFromOptions>> ranges, Range<Token> toSubtract) |
| { |
| Set<Range<Token>> result = new HashSet<>(); |
| result.add(toSubtract); |
| for(Map.Entry<Range<Token>, StreamFromOptions> range : ranges) |
| { |
| result = substractAllFromToken(result, range.getKey()); |
| } |
| |
| return result; |
| } |
| |
| private static <T extends RingPosition<T>> Set<Range<T>> substractAllFromToken(Set<Range<T>> ranges, Range<T> subtract) |
| { |
| Set<Range<T>> result = new HashSet<>(); |
| for(Range<T> range : ranges) |
| { |
| result.addAll(range.subtract(subtract)); |
| } |
| |
| return result; |
| } |
| } |