Java tutorial
/** * Copyright 2011-2016 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.testdriver.hadoop; import java.io.File; import java.net.MalformedURLException; import java.net.URL; import java.text.MessageFormat; import java.util.HashMap; import java.util.Map; import org.apache.hadoop.conf.Configuration; import org.apache.hadoop.fs.LocalFileSystem; import org.slf4j.Logger; import org.slf4j.LoggerFactory; import com.asakusafw.runtime.util.hadoop.ConfigurationProvider; import com.asakusafw.testdriver.core.TestingEnvironmentConfigurator; /** * Creates {@link Configuration}s with system defaults. * @since 0.2.5 * @version 0.6.0 */ public class ConfigurationFactory extends ConfigurationProvider { static final Logger LOG = LoggerFactory.getLogger(ConfigurationFactory.class); /** * The system property key of {@link LocalFileSystem} implementation class name. * @since 0.6.0 */ public static final String KEY_LOCAL_FILE_SYSTEM = "asakusa.testdriver.fs"; //$NON-NLS-1$ /** * The system property key of Hadoop configuration path. * @since 0.6.0 */ public static final String KEY_EXPLICIT_HADOOP_CONF = "asakusa.testdriver.hadoop.conf"; //$NON-NLS-1$ /** * The system property key of Hadoop command path. * @since 0.6.0 */ public static final String KEY_EXPLICIT_HADOOP_COMMAND = "asakusa.testdriver.hadoop.command"; //$NON-NLS-1$ /** * The default value of {@link LocalFileSystem} implementation class name. */ static final String DEFAULT_LOCAL_FILE_SYSTEM = AsakusaTestLocalFileSystem.class.getName(); static { TestingEnvironmentConfigurator.initialize(); } private final Preferences preferences; /** * Creates a new instance. * @see #getDefault() */ private ConfigurationFactory() { this(Preferences.getDefault()); } /** * Creates a new instance. * @param defaultConfigPath the default configuration path * @see #getDefault() */ public ConfigurationFactory(URL defaultConfigPath) { super(defaultConfigPath); this.preferences = Preferences.getDefault(); } /** * Creates a new instance. * @param preferences the preferences for this instance * @see #getDefault() * @since 0.6.0 */ public ConfigurationFactory(Preferences preferences) { super(preferences.getConfigurationPath()); this.preferences = preferences; } /** * Returns a default factory which refers the System Hadoop configuration path. * <p> * If Hadoop installation is not found in your system, * this returns a factory which use the current context classloader. * </p> * @return a default factory object */ public static ConfigurationFactory getDefault() { return new ConfigurationFactory(); } /** * Returns the Hadoop command path for this configuration. * @return the Hadoop command path, or {@code null} if it is not found */ public File getHadoopCommand() { return preferences.getHadoopCommand(); } @Override protected void configure(Configuration configuration) { if (preferences.getLocalFileSystemClassName() != null) { configuration.set("fs.file.impl", preferences.getLocalFileSystemClassName()); //$NON-NLS-1$ configuration.setBoolean("fs.fs.impl.disable.cache", true); //$NON-NLS-1$ } } /** * Preferences for {@link ConfigurationFactory}. * @since 0.6.0 */ public static class Preferences { private String localFileSystemClassName; private File explicitConfigurationPath; private File explicitCommandPath; private final Map<String, String> environmentVariables = new HashMap<>(System.getenv()); /** * Sets the implementation class name of {@link LocalFileSystem}. * @param className the class name */ public void setLocalFileSystemClassName(String className) { this.localFileSystemClassName = className; } /** * Sets the explicit Hadoop configuration path. * @param path the Hadoop configuration path, or {@code null} if it should be inferred */ public void setExplicitConfigurationPath(File path) { this.explicitConfigurationPath = path; } /** * Sets the explicit Hadoop command path. * @param path the Hadoop command path, or {@code null} if it should be inferred */ public void setExplicitCommandPath(File path) { this.explicitCommandPath = path; } /** * Returns the implementation class name of {@link LocalFileSystem}. * @return the class name, or {@code null} if it is not defined */ public String getLocalFileSystemClassName() { return localFileSystemClassName; } /** * Returns the current environment variables. * Clients can modify the returned map. * @return the environment variables */ public Map<String, String> getEnvironmentVariables() { return environmentVariables; } /** * Returns the explicitly defined Hadoop configuration path. * @return the explicit Hadoop configuration path, or {@code null} if it is not defined */ public File getExplicitConfigurationPath() { return explicitConfigurationPath; } /** * Returns the explicitly defined Hadoop command path. * @return the explicit Hadoop command path, or {@code null} if it is not defined */ public File getExplicitCommandPath() { return explicitCommandPath; } /** * Returns the Hadoop configuration path. * @return the Hadoop configuration path, or {@code null} if it is not found * @see #getExplicitConfigurationPath() */ public URL getConfigurationPath() { if (explicitConfigurationPath != null) { try { return explicitConfigurationPath.toURI().toURL(); } catch (MalformedURLException e) { LOG.error(MessageFormat.format( Messages.getString("ConfigurationFactory.errorInvalidHadoopConfigurationPath"), //$NON-NLS-1$ explicitConfigurationPath), e); } } return ConfigurationProvider.getConfigurationPath(environmentVariables); } /** * Returns the Hadoop command path. * @return the Hadoop command path, or {@code null} if it is not found */ public File getHadoopCommand() { if (explicitCommandPath != null) { return explicitCommandPath; } return ConfigurationProvider.findHadoopCommand(environmentVariables); } /** * Returns a {@link Preferences} with default values. * @return default preferences */ public static Preferences getDefault() { Preferences prefs = new Preferences(); prefs.setLocalFileSystemClassName(System.getProperty(KEY_LOCAL_FILE_SYSTEM, DEFAULT_LOCAL_FILE_SYSTEM)); prefs.setExplicitConfigurationPath(getFile(KEY_EXPLICIT_HADOOP_CONF)); prefs.setExplicitCommandPath(getFile(KEY_EXPLICIT_HADOOP_COMMAND)); return prefs; } private static File getFile(String key) { String value = System.getProperty(key); if (value == null) { return null; } return new File(value); } } }