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.bridge.launch; import java.io.File; import java.io.FileInputStream; import java.io.IOException; import java.io.InputStream; import java.text.MessageFormat; import java.util.Collections; import java.util.Map; import java.util.Set; import java.util.TreeMap; import org.apache.hadoop.conf.Configuration; import org.slf4j.Logger; import org.slf4j.LoggerFactory; /** * A {@link LaunchOption} for Hadoop platform. */ public class HadoopPropertiesOption extends AbstractPropertiesOption { static final Logger LOG = LoggerFactory.getLogger(HadoopPropertiesOption.class); /** * The command name. */ public static final String COMMAND = "--hadoop-conf"; //$NON-NLS-1$ @Override public Set<String> getCommands() { return Collections.singleton(COMMAND); } @Override protected Map<String, String> extract(File file) throws LaunchConfigurationException { LOG.debug("loading file: {} ({})", file, COMMAND); //$NON-NLS-1$ Configuration configuration = new Configuration(false); try (InputStream in = new FileInputStream(file)) { configuration.addResource(in); Map<String, String> results = new TreeMap<>(); for (Map.Entry<String, String> entry : configuration) { results.put(entry.getKey(), entry.getValue()); } return results; } catch (IOException e) { throw new LaunchConfigurationException(MessageFormat .format("error occurred while loading configuration file: {1} ({0})", COMMAND, file), e); } } }