| /* |
| * 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.sai.disk.v1.segment; |
| |
| import java.io.Closeable; |
| import java.io.IOException; |
| import java.util.List; |
| |
| import com.google.common.annotations.VisibleForTesting; |
| |
| import org.apache.cassandra.db.PartitionPosition; |
| import org.apache.cassandra.dht.AbstractBounds; |
| import org.apache.cassandra.dht.Range; |
| import org.apache.cassandra.dht.Token; |
| import org.apache.cassandra.index.sai.IndexContext; |
| import org.apache.cassandra.index.sai.QueryContext; |
| import org.apache.cassandra.index.sai.SSTableContext; |
| import org.apache.cassandra.index.sai.disk.PrimaryKeyMap; |
| import org.apache.cassandra.index.sai.disk.v1.PerColumnIndexFiles; |
| import org.apache.cassandra.index.sai.plan.Expression; |
| import org.apache.cassandra.index.sai.iterators.KeyRangeIterator; |
| import org.apache.cassandra.index.sai.utils.PrimaryKey; |
| import org.apache.cassandra.io.util.FileUtils; |
| |
| /** |
| * Each segment represents an on-disk index structure (balanced tree/terms/postings) flushed by memory limit or token boundaries. |
| * It also helps to reduce resource consumption for read requests as only segments that intersect with read request data |
| * range need to be loaded. |
| */ |
| public class Segment implements SegmentOrdering, Closeable |
| { |
| private final Token.KeyBound minKeyBound; |
| private final Token.KeyBound maxKeyBound; |
| |
| // per sstable |
| final PrimaryKeyMap.Factory primaryKeyMapFactory; |
| // per-segment |
| public final SegmentMetadata metadata; |
| |
| private final IndexSegmentSearcher index; |
| |
| public Segment(IndexContext indexContext, SSTableContext sstableContext, PerColumnIndexFiles indexFiles, SegmentMetadata metadata) throws IOException |
| { |
| this.minKeyBound = metadata.minKey.token().minKeyBound(); |
| this.maxKeyBound = metadata.maxKey.token().maxKeyBound(); |
| |
| this.primaryKeyMapFactory = sstableContext.primaryKeyMapFactory; |
| this.metadata = metadata; |
| |
| this.index = IndexSegmentSearcher.open(primaryKeyMapFactory, indexFiles, metadata, indexContext); |
| } |
| |
| @VisibleForTesting |
| public Segment(Token minKey, Token maxKey) |
| { |
| this.primaryKeyMapFactory = null; |
| this.metadata = null; |
| this.minKeyBound = minKey.minKeyBound(); |
| this.maxKeyBound = maxKey.maxKeyBound(); |
| this.index = null; |
| } |
| |
| /** |
| * @return true if current segment intersects with query key range |
| */ |
| public boolean intersects(AbstractBounds<PartitionPosition> keyRange) |
| { |
| if (keyRange instanceof Range && ((Range<?>)keyRange).isWrapAround()) |
| return keyRange.contains(minKeyBound) || keyRange.contains(maxKeyBound); |
| |
| int cmp = keyRange.right.compareTo(minKeyBound); |
| // if right is minimum, it means right is the max token and bigger than maxKey. |
| // if right bound is less than minKeyBound, no intersection |
| if (!keyRange.right.isMinimum() && (!keyRange.inclusiveRight() && cmp == 0 || cmp < 0)) |
| return false; |
| |
| cmp = keyRange.left.compareTo(maxKeyBound); |
| // if left bound is bigger than maxKeyBound, no intersection |
| return (keyRange.isStartInclusive() || cmp != 0) && cmp <= 0; |
| } |
| |
| public long indexFileCacheSize() |
| { |
| return index == null ? 0 : index.indexFileCacheSize(); |
| } |
| |
| /** |
| * Search on-disk index synchronously |
| * |
| * @param expression to filter on disk index |
| * @param context to track per sstable cache and per query metrics |
| |
| * @return range iterator that matches given expression |
| */ |
| public KeyRangeIterator search(Expression expression, AbstractBounds<PartitionPosition> keyRange, QueryContext context) throws IOException |
| { |
| return index.search(expression, keyRange, context); |
| } |
| |
| @Override |
| public KeyRangeIterator limitToTopKResults(QueryContext context, List<PrimaryKey> primaryKeys, Expression expression) throws IOException |
| { |
| return index.limitToTopKResults(context, primaryKeys, expression); |
| } |
| |
| @Override |
| public void close() |
| { |
| FileUtils.closeQuietly(index); |
| } |
| |
| @Override |
| public String toString() |
| { |
| return String.format("Segment{metadata=%s}", metadata); |
| } |
| } |