Java tutorial
/** * Copyright 2011-2017 Asakusa Framework Team. * * Licensed 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 com.asakusafw.runtime.util.cache; import static org.hamcrest.Matchers.*; import static org.junit.Assert.*; import java.io.File; import java.io.FileOutputStream; import java.io.OutputStream; import java.util.ArrayList; import java.util.List; import java.util.concurrent.CountDownLatch; import java.util.concurrent.ExecutorService; import java.util.concurrent.Executors; import java.util.concurrent.Future; import java.util.concurrent.TimeUnit; import java.util.concurrent.TimeoutException; import org.apache.commons.logging.Log; import org.apache.commons.logging.LogFactory; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.Path; import org.junit.Assume; import org.junit.ClassRule; import org.junit.Test; import com.asakusafw.runtime.util.hadoop.ConfigurationProvider; import com.asakusafw.runtime.util.lock.ConstantRetryStrategy; import com.asakusafw.runtime.util.lock.LocalFileLockProvider; import com.asakusafw.runtime.util.lock.LockProvider; import com.asakusafw.runtime.util.lock.RetryStrategy; import com.asakusafw.runtime.windows.WindowsSupport; /** * Test for {@link FileCacheRepository}. */ public class HadoopFileCacheRepositoryTest extends FileCacheRepositoryTestRoot { /** * Windows platform support. */ @ClassRule public static final WindowsSupport WINDOWS_SUPPORT = new WindowsSupport(); static final Log LOG = LogFactory.getLog(HadoopFileCacheRepositoryTest.class); /** * simple case. * @throws Exception if failed */ @Test public void simple() throws Exception { File cacheRepo = folder.newFolder(); Configuration configuration = new ConfigurationProvider().newInstance(); LockProvider<Path> locks = new LocalFileLockProvider<>(folder.newFolder()); RetryStrategy retrier = new ConstantRetryStrategy(); HadoopFileCacheRepository cache = new HadoopFileCacheRepository(configuration, path(cacheRepo), locks, retrier); File source = put(folder.newFile(), "Hello, world!"); Path resolved = cache.resolve(path(source)); assertThat(get(file(resolved)), is("Hello, world!")); assertThat(resolved, is(not(path(source)))); assertThat(containsFile(cacheRepo, file(resolved)), is(true)); } /** * update cache. * @throws Exception if failed */ @Test public void update() throws Exception { File cacheRepo = folder.newFolder(); Configuration configuration = new ConfigurationProvider().newInstance(); LockProvider<Path> locks = new LocalFileLockProvider<>(folder.newFolder()); RetryStrategy retrier = new ConstantRetryStrategy(); HadoopFileCacheRepository cache = new HadoopFileCacheRepository(configuration, path(cacheRepo), locks, retrier); File source = put(folder.newFile(), "Hello, world!"); Path first = cache.resolve(path(source)); put(source, "UPDATED"); Path retry = cache.resolve(path(source)); assertThat(retry, is(first)); assertThat(get(file(retry)), is("UPDATED")); } /** * use cached. * @throws Exception if failed */ @Test public void cached() throws Exception { File cacheRepo = folder.newFolder(); Configuration configuration = new ConfigurationProvider().newInstance(); LockProvider<Path> locks = new LocalFileLockProvider<>(folder.newFolder()); RetryStrategy retrier = new ConstantRetryStrategy(); HadoopFileCacheRepository cache = new HadoopFileCacheRepository(configuration, path(cacheRepo), locks, retrier); File source = put(folder.newFile(), "Hello, world!"); Path first = cache.resolve(path(source)); long timestamp = file(first).lastModified(); Assume.assumeThat(timestamp, is(greaterThan(0L))); for (int i = 0; i < 10; i++) { if (System.currentTimeMillis() != timestamp) { break; } Thread.sleep(10); } Assume.assumeThat(System.currentTimeMillis(), is(not(timestamp))); // may not changed Path retry = cache.resolve(path(source)); assertThat(file(retry).lastModified(), is(timestamp)); } /** * Conflict cache creation. * @throws Exception if failed */ @Test public void conflict() throws Exception { File source = folder.newFile(); byte[] bytes = new byte[1024 * 1024]; try (OutputStream output = new FileOutputStream(source)) { for (int i = 0, n = 50; i < n; i++) { output.write(bytes); } } Path path = path(source); File cacheRepo = folder.newFolder(); Configuration configuration = new ConfigurationProvider().newInstance(); LockProvider<Path> locks = new LocalFileLockProvider<>(folder.newFolder()); RetryStrategy retrier = new ConstantRetryStrategy(30, 100, 200); FileCacheRepository cache = new HadoopFileCacheRepository(configuration, path(cacheRepo), locks, retrier); List<Future<Path>> futures = new ArrayList<>(); int count = 10; CountDownLatch latch = new CountDownLatch(count); ExecutorService executor = Executors.newFixedThreadPool(count); try { for (int i = 0; i < count; i++) { String label = String.format("thread-%d", i); futures.add(executor.submit(() -> { LOG.info("Wait: resolve @" + label); latch.countDown(); if (latch.await(5, TimeUnit.SECONDS) == false) { throw new TimeoutException(); } LOG.info("Start: resolve @" + label); Path result = cache.resolve(path); LOG.info("Finish: resolve @" + label); return result; })); } executor.shutdown(); if (executor.awaitTermination(30, TimeUnit.SECONDS) == false) { throw new TimeoutException(); } } finally { executor.shutdownNow(); } for (Future<Path> future : futures) { future.get(); } } }