Java tutorial
/* * Licensed to Elasticsearch under one or more contributor * license agreements. See the NOTICE file distributed with * this work for additional information regarding copyright * ownership. Elasticsearch 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.elasticsearch.indices; import org.apache.lucene.document.Document; import org.apache.lucene.index.DirectoryReader; import org.apache.lucene.index.IndexWriter; import org.apache.lucene.index.LeafReaderContext; import org.apache.lucene.search.ConstantScoreScorer; import org.apache.lucene.search.ConstantScoreWeight; import org.apache.lucene.search.DocIdSetIterator; import org.apache.lucene.search.IndexSearcher; import org.apache.lucene.search.Query; import org.apache.lucene.search.QueryCachingPolicy; import org.apache.lucene.search.Scorer; import org.apache.lucene.search.Weight; import org.apache.lucene.store.Directory; import org.apache.lucene.util.IOUtils; import org.elasticsearch.common.lucene.index.ElasticsearchDirectoryReader; import org.elasticsearch.common.settings.Settings; import org.elasticsearch.index.IndexModule; import org.elasticsearch.index.cache.query.QueryCacheStats; import org.elasticsearch.index.shard.ShardId; import org.elasticsearch.indices.IndicesQueryCache; import org.elasticsearch.test.ESTestCase; import java.io.IOException; public class IndicesQueryCacheTests extends ESTestCase { private static class DummyQuery extends Query { private final int id; DummyQuery(int id) { this.id = id; } @Override public boolean equals(Object obj) { return sameClassAs(obj) && id == ((DummyQuery) obj).id; } @Override public int hashCode() { return 31 * classHash() + id; } @Override public String toString(String field) { return "dummy"; } @Override public Weight createWeight(IndexSearcher searcher, boolean needsScores) throws IOException { return new ConstantScoreWeight(this) { @Override public Scorer scorer(LeafReaderContext context) throws IOException { return new ConstantScoreScorer(this, score(), DocIdSetIterator.all(context.reader().maxDoc())); } }; } } public void testBasics() throws IOException { Directory dir = newDirectory(); IndexWriter w = new IndexWriter(dir, newIndexWriterConfig()); w.addDocument(new Document()); DirectoryReader r = DirectoryReader.open(w); w.close(); ShardId shard = new ShardId("index", "_na_", 0); r = ElasticsearchDirectoryReader.wrap(r, shard); IndexSearcher s = new IndexSearcher(r); s.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE); Settings settings = Settings.builder().put(IndicesQueryCache.INDICES_CACHE_QUERY_COUNT_SETTING.getKey(), 10) .put(IndicesQueryCache.INDICES_QUERIES_CACHE_ALL_SEGMENTS_SETTING.getKey(), true).build(); IndicesQueryCache cache = new IndicesQueryCache(settings); s.setQueryCache(cache); QueryCacheStats stats = cache.getStats(shard); assertEquals(0L, stats.getCacheSize()); assertEquals(0L, stats.getCacheCount()); assertEquals(0L, stats.getHitCount()); assertEquals(0L, stats.getMissCount()); assertEquals(1, s.count(new DummyQuery(0))); stats = cache.getStats(shard); assertEquals(1L, stats.getCacheSize()); assertEquals(1L, stats.getCacheCount()); assertEquals(0L, stats.getHitCount()); assertEquals(1L, stats.getMissCount()); for (int i = 1; i < 20; ++i) { assertEquals(1, s.count(new DummyQuery(i))); } stats = cache.getStats(shard); assertEquals(10L, stats.getCacheSize()); assertEquals(20L, stats.getCacheCount()); assertEquals(0L, stats.getHitCount()); assertEquals(20L, stats.getMissCount()); s.count(new DummyQuery(10)); stats = cache.getStats(shard); assertEquals(10L, stats.getCacheSize()); assertEquals(20L, stats.getCacheCount()); assertEquals(1L, stats.getHitCount()); assertEquals(20L, stats.getMissCount()); IOUtils.close(r, dir); // got emptied, but no changes to other metrics stats = cache.getStats(shard); assertEquals(0L, stats.getCacheSize()); assertEquals(20L, stats.getCacheCount()); assertEquals(1L, stats.getHitCount()); assertEquals(20L, stats.getMissCount()); cache.onClose(shard); // forgot everything stats = cache.getStats(shard); assertEquals(0L, stats.getCacheSize()); assertEquals(0L, stats.getCacheCount()); assertEquals(0L, stats.getHitCount()); assertEquals(0L, stats.getMissCount()); cache.close(); // this triggers some assertions } public void testTwoShards() throws IOException { Directory dir1 = newDirectory(); IndexWriter w1 = new IndexWriter(dir1, newIndexWriterConfig()); w1.addDocument(new Document()); DirectoryReader r1 = DirectoryReader.open(w1); w1.close(); ShardId shard1 = new ShardId("index", "_na_", 0); r1 = ElasticsearchDirectoryReader.wrap(r1, shard1); IndexSearcher s1 = new IndexSearcher(r1); s1.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE); Directory dir2 = newDirectory(); IndexWriter w2 = new IndexWriter(dir2, newIndexWriterConfig()); w2.addDocument(new Document()); DirectoryReader r2 = DirectoryReader.open(w2); w2.close(); ShardId shard2 = new ShardId("index", "_na_", 1); r2 = ElasticsearchDirectoryReader.wrap(r2, shard2); IndexSearcher s2 = new IndexSearcher(r2); s2.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE); Settings settings = Settings.builder().put(IndicesQueryCache.INDICES_CACHE_QUERY_COUNT_SETTING.getKey(), 10) .put(IndicesQueryCache.INDICES_QUERIES_CACHE_ALL_SEGMENTS_SETTING.getKey(), true).build(); IndicesQueryCache cache = new IndicesQueryCache(settings); s1.setQueryCache(cache); s2.setQueryCache(cache); assertEquals(1, s1.count(new DummyQuery(0))); QueryCacheStats stats1 = cache.getStats(shard1); assertEquals(1L, stats1.getCacheSize()); assertEquals(1L, stats1.getCacheCount()); assertEquals(0L, stats1.getHitCount()); assertEquals(1L, stats1.getMissCount()); QueryCacheStats stats2 = cache.getStats(shard2); assertEquals(0L, stats2.getCacheSize()); assertEquals(0L, stats2.getCacheCount()); assertEquals(0L, stats2.getHitCount()); assertEquals(0L, stats2.getMissCount()); assertEquals(1, s2.count(new DummyQuery(0))); stats1 = cache.getStats(shard1); assertEquals(1L, stats1.getCacheSize()); assertEquals(1L, stats1.getCacheCount()); assertEquals(0L, stats1.getHitCount()); assertEquals(1L, stats1.getMissCount()); stats2 = cache.getStats(shard2); assertEquals(1L, stats2.getCacheSize()); assertEquals(1L, stats2.getCacheCount()); assertEquals(0L, stats2.getHitCount()); assertEquals(1L, stats2.getMissCount()); for (int i = 0; i < 20; ++i) { assertEquals(1, s2.count(new DummyQuery(i))); } stats1 = cache.getStats(shard1); assertEquals(0L, stats1.getCacheSize()); // evicted assertEquals(1L, stats1.getCacheCount()); assertEquals(0L, stats1.getHitCount()); assertEquals(1L, stats1.getMissCount()); stats2 = cache.getStats(shard2); assertEquals(10L, stats2.getCacheSize()); assertEquals(20L, stats2.getCacheCount()); assertEquals(1L, stats2.getHitCount()); assertEquals(20L, stats2.getMissCount()); IOUtils.close(r1, dir1); // no changes stats1 = cache.getStats(shard1); assertEquals(0L, stats1.getCacheSize()); assertEquals(1L, stats1.getCacheCount()); assertEquals(0L, stats1.getHitCount()); assertEquals(1L, stats1.getMissCount()); stats2 = cache.getStats(shard2); assertEquals(10L, stats2.getCacheSize()); assertEquals(20L, stats2.getCacheCount()); assertEquals(1L, stats2.getHitCount()); assertEquals(20L, stats2.getMissCount()); cache.onClose(shard1); // forgot everything about shard1 stats1 = cache.getStats(shard1); assertEquals(0L, stats1.getCacheSize()); assertEquals(0L, stats1.getCacheCount()); assertEquals(0L, stats1.getHitCount()); assertEquals(0L, stats1.getMissCount()); stats2 = cache.getStats(shard2); assertEquals(10L, stats2.getCacheSize()); assertEquals(20L, stats2.getCacheCount()); assertEquals(1L, stats2.getHitCount()); assertEquals(20L, stats2.getMissCount()); IOUtils.close(r2, dir2); cache.onClose(shard2); // forgot everything about shard2 stats1 = cache.getStats(shard1); assertEquals(0L, stats1.getCacheSize()); assertEquals(0L, stats1.getCacheCount()); assertEquals(0L, stats1.getHitCount()); assertEquals(0L, stats1.getMissCount()); stats2 = cache.getStats(shard2); assertEquals(0L, stats2.getCacheSize()); assertEquals(0L, stats2.getCacheCount()); assertEquals(0L, stats2.getHitCount()); assertEquals(0L, stats2.getMissCount()); cache.close(); // this triggers some assertions } // Make sure the cache behaves correctly when a segment that is associated // with an empty cache gets closed. In that particular case, the eviction // callback is called with a number of evicted entries equal to 0 // see https://github.com/elastic/elasticsearch/issues/15043 public void testStatsOnEviction() throws IOException { Directory dir1 = newDirectory(); IndexWriter w1 = new IndexWriter(dir1, newIndexWriterConfig()); w1.addDocument(new Document()); DirectoryReader r1 = DirectoryReader.open(w1); w1.close(); ShardId shard1 = new ShardId("index", "_na_", 0); r1 = ElasticsearchDirectoryReader.wrap(r1, shard1); IndexSearcher s1 = new IndexSearcher(r1); s1.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE); Directory dir2 = newDirectory(); IndexWriter w2 = new IndexWriter(dir2, newIndexWriterConfig()); w2.addDocument(new Document()); DirectoryReader r2 = DirectoryReader.open(w2); w2.close(); ShardId shard2 = new ShardId("index", "_na_", 1); r2 = ElasticsearchDirectoryReader.wrap(r2, shard2); IndexSearcher s2 = new IndexSearcher(r2); s2.setQueryCachingPolicy(QueryCachingPolicy.ALWAYS_CACHE); Settings settings = Settings.builder().put(IndicesQueryCache.INDICES_CACHE_QUERY_COUNT_SETTING.getKey(), 10) .put(IndicesQueryCache.INDICES_QUERIES_CACHE_ALL_SEGMENTS_SETTING.getKey(), true).build(); IndicesQueryCache cache = new IndicesQueryCache(settings); s1.setQueryCache(cache); s2.setQueryCache(cache); assertEquals(1, s1.count(new DummyQuery(0))); for (int i = 1; i <= 20; ++i) { assertEquals(1, s2.count(new DummyQuery(i))); } QueryCacheStats stats1 = cache.getStats(shard1); assertEquals(0L, stats1.getCacheSize()); assertEquals(1L, stats1.getCacheCount()); // this used to fail because we were evicting an empty cache on // the segment from r1 IOUtils.close(r1, dir1); cache.onClose(shard1); IOUtils.close(r2, dir2); cache.onClose(shard2); cache.close(); // this triggers some assertions } }