| /* |
| * 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.jackrabbit.oak.segment; |
| |
| import static java.lang.String.valueOf; |
| import static org.junit.Assert.assertEquals; |
| import static org.junit.Assert.assertTrue; |
| |
| import java.util.ArrayList; |
| import java.util.Random; |
| import java.util.concurrent.atomic.AtomicInteger; |
| |
| import org.jetbrains.annotations.NotNull; |
| import org.jetbrains.annotations.Nullable; |
| import org.junit.Test; |
| |
| import com.google.common.base.Function; |
| |
| public class ReaderCacheTest { |
| |
| @Test |
| public void empty() { |
| final AtomicInteger counter = new AtomicInteger(); |
| Function<Integer, String> loader = new Function<Integer, String>() { |
| @Override @NotNull |
| public String apply(@Nullable Integer input) { |
| counter.incrementAndGet(); |
| return valueOf(input); |
| } |
| }; |
| StringCache c = new StringCache(0); |
| for (int repeat = 0; repeat < 10; repeat++) { |
| for (int i = 0; i < 1000; i++) { |
| assertEquals(valueOf(i), c.get(i, i, i, loader)); |
| } |
| } |
| // the LIRS cache should be almost empty (low hit rate there) |
| assertTrue(valueOf(counter), counter.get() > 1000); |
| // but the fast cache should improve the total hit rate |
| assertTrue(valueOf(counter), counter.get() < 5000); |
| } |
| |
| @Test |
| public void largeEntries() { |
| final AtomicInteger counter = new AtomicInteger(); |
| final String large = new String(new char[1024]); |
| Function<Integer, String> loader = new Function<Integer, String>() { |
| @Override @Nullable |
| public String apply(@Nullable Integer input) { |
| counter.incrementAndGet(); |
| return large + input; |
| } |
| }; |
| StringCache c = new StringCache(1024); |
| for (int repeat = 0; repeat < 10; repeat++) { |
| for (int i = 0; i < 1000; i++) { |
| assertEquals(large + i, c.get(i, i, i, loader)); |
| assertEquals(large + 0, c.get(0, 0, 0, loader)); |
| } |
| } |
| // the LIRS cache should be almost empty (low hit rate there) |
| // and large strings are not kept in the fast cache, so hit rate should be bad |
| assertTrue(valueOf(counter), counter.get() > 9000); |
| assertTrue(valueOf(counter), counter.get() < 10000); |
| } |
| |
| @Test |
| public void clear() { |
| final AtomicInteger counter = new AtomicInteger(); |
| Function<Integer, String> uniqueLoader = new Function<Integer, String>() { |
| @Override @Nullable |
| public String apply(@Nullable Integer input) { |
| return valueOf(counter.incrementAndGet()); |
| } |
| }; |
| StringCache c = new StringCache(0); |
| // load a new entry |
| assertEquals("1", c.get(0, 0, 0, uniqueLoader)); |
| // but only once |
| assertEquals("1", c.get(0, 0, 0, uniqueLoader)); |
| c.clear(); |
| // after clearing the cache, load a new entry |
| assertEquals("2", c.get(0, 0, 0, uniqueLoader)); |
| assertEquals("2", c.get(0, 0, 0, uniqueLoader)); |
| } |
| |
| @Test |
| public void randomized() { |
| ArrayList<Function<Integer, String>> loaderList = new ArrayList<Function<Integer, String>>(); |
| int segmentCount = 10; |
| for (int i = 0; i < segmentCount; i++) { |
| final int x = i; |
| Function<Integer, String> loader = new Function<Integer, String>() { |
| @Override @Nullable |
| public String apply(@Nullable Integer input) { |
| return "loader #" + x + " offset " + input; |
| } |
| }; |
| loaderList.add(loader); |
| } |
| StringCache c = new StringCache(10); |
| Random r = new Random(1); |
| for (int i = 0; i < 1000; i++) { |
| int segment = r.nextInt(segmentCount); |
| int offset = r.nextInt(10); |
| Function<Integer, String> loader = loaderList.get(segment); |
| String x = c.get(segment, segment, offset, loader); |
| assertEquals(loader.apply(offset), x); |
| } |
| } |
| |
| } |