| /* |
| * 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.index.sasi.memory; |
| |
| import java.nio.ByteBuffer; |
| import java.util.*; |
| import java.util.concurrent.ConcurrentSkipListMap; |
| import java.util.concurrent.ConcurrentSkipListSet; |
| |
| import org.apache.cassandra.db.DecoratedKey; |
| import org.apache.cassandra.index.sasi.conf.ColumnIndex; |
| import org.apache.cassandra.index.sasi.disk.Token; |
| import org.apache.cassandra.index.sasi.plan.Expression; |
| import org.apache.cassandra.index.sasi.utils.RangeUnionIterator; |
| import org.apache.cassandra.index.sasi.utils.RangeIterator; |
| import org.apache.cassandra.db.marshal.AbstractType; |
| |
| public class SkipListMemIndex extends MemIndex |
| { |
| public static final int CSLM_OVERHEAD = 128; // average overhead of CSLM |
| |
| private final ConcurrentSkipListMap<ByteBuffer, ConcurrentSkipListSet<DecoratedKey>> index; |
| |
| public SkipListMemIndex(AbstractType<?> keyValidator, ColumnIndex columnIndex) |
| { |
| super(keyValidator, columnIndex); |
| index = new ConcurrentSkipListMap<>(columnIndex.getValidator()); |
| } |
| |
| public long add(DecoratedKey key, ByteBuffer value) |
| { |
| long overhead = CSLM_OVERHEAD; // DKs are shared |
| ConcurrentSkipListSet<DecoratedKey> keys = index.get(value); |
| |
| if (keys == null) |
| { |
| ConcurrentSkipListSet<DecoratedKey> newKeys = new ConcurrentSkipListSet<>(DecoratedKey.comparator); |
| keys = index.putIfAbsent(value, newKeys); |
| if (keys == null) |
| { |
| overhead += CSLM_OVERHEAD + value.remaining(); |
| keys = newKeys; |
| } |
| } |
| |
| keys.add(key); |
| |
| return overhead; |
| } |
| |
| public RangeIterator<Long, Token> search(Expression expression) |
| { |
| ByteBuffer min = expression.lower == null ? null : expression.lower.value; |
| ByteBuffer max = expression.upper == null ? null : expression.upper.value; |
| |
| SortedMap<ByteBuffer, ConcurrentSkipListSet<DecoratedKey>> search; |
| |
| if (min == null && max == null) |
| { |
| throw new IllegalArgumentException(); |
| } |
| if (min != null && max != null) |
| { |
| search = index.subMap(min, expression.lower.inclusive, max, expression.upper.inclusive); |
| } |
| else if (min == null) |
| { |
| search = index.headMap(max, expression.upper.inclusive); |
| } |
| else |
| { |
| search = index.tailMap(min, expression.lower.inclusive); |
| } |
| |
| RangeUnionIterator.Builder<Long, Token> builder = RangeUnionIterator.builder(); |
| search.values().stream() |
| .filter(keys -> !keys.isEmpty()) |
| .forEach(keys -> builder.add(new KeyRangeIterator(keys))); |
| |
| return builder.build(); |
| } |
| } |