Java tutorial
/* * 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.tinkerpop.gremlin.hadoop.structure; import org.apache.commons.configuration.AbstractConfiguration; import org.apache.commons.configuration.Configuration; import org.apache.hadoop.io.NullWritable; import org.apache.hadoop.mapreduce.InputFormat; import org.apache.hadoop.mapreduce.OutputFormat; import org.apache.tinkerpop.gremlin.hadoop.Constants; import org.apache.tinkerpop.gremlin.hadoop.structure.io.VertexWritable; import org.apache.tinkerpop.gremlin.util.iterator.IteratorUtils; import org.javatuples.Pair; import java.io.Serializable; import java.util.HashMap; import java.util.Iterator; import java.util.Map; /** * @author Marko A. Rodriguez (http://markorodriguez.com) */ public final class HadoopConfiguration extends AbstractConfiguration implements Serializable, Iterable { private final Map<String, Object> properties = new HashMap<>(); public HadoopConfiguration() { super(); super.setDelimiterParsingDisabled(true); } public HadoopConfiguration(final Configuration configuration) { this(); this.copy(configuration); } @Override protected void addPropertyDirect(final String key, final Object value) { this.properties.put(key, value); } @Override protected void clearPropertyDirect(final String key) { this.properties.remove(key); } @Override public boolean isEmpty() { return this.properties.isEmpty(); } @Override public boolean containsKey(final String key) { return this.properties.containsKey(key); } @Override public Object getProperty(final String key) { return this.properties.get(key); } @Override public Iterator<String> getKeys() { return this.properties.keySet().iterator(); } /////// public Class<InputFormat<NullWritable, VertexWritable>> getGraphInputFormat() { try { return (Class) Class.forName(this.getString(Constants.GREMLIN_HADOOP_GRAPH_INPUT_FORMAT)); } catch (final ClassNotFoundException e) { throw new RuntimeException(e.getMessage(), e); } } public Class<OutputFormat<NullWritable, VertexWritable>> getGraphOutputFormat() { try { return (Class) Class.forName(this.getString(Constants.GREMLIN_HADOOP_GRAPH_OUTPUT_FORMAT)); } catch (final ClassNotFoundException e) { throw new RuntimeException(e.getMessage(), e); } } public String getInputLocation() { return this.getString(Constants.GREMLIN_HADOOP_INPUT_LOCATION); } public void setInputLocation(final String inputLocation) { this.setProperty(Constants.GREMLIN_HADOOP_INPUT_LOCATION, inputLocation); } public String getOutputLocation() { return this.getString(Constants.GREMLIN_HADOOP_OUTPUT_LOCATION); } public void setOutputLocation(final String outputLocation) { this.setProperty(Constants.GREMLIN_HADOOP_OUTPUT_LOCATION, outputLocation); } @Override public Iterator iterator() { return IteratorUtils.map(this.getKeys(), k -> new Pair<>(k, this.getProperty(k))); } }