| /* |
| * 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.process.computer; |
| |
| import org.apache.hadoop.conf.Configuration; |
| import org.apache.hadoop.io.NullWritable; |
| import org.apache.hadoop.mapreduce.InputFormat; |
| import org.apache.hadoop.mapreduce.InputSplit; |
| import org.apache.hadoop.mapreduce.RecordReader; |
| import org.apache.hadoop.mapreduce.TaskAttemptContext; |
| import org.apache.hadoop.util.ReflectionUtils; |
| import org.apache.tinkerpop.gremlin.hadoop.Constants; |
| import org.apache.tinkerpop.gremlin.hadoop.structure.io.GraphFilterAware; |
| import org.apache.tinkerpop.gremlin.hadoop.structure.io.VertexWritable; |
| import org.apache.tinkerpop.gremlin.hadoop.structure.util.ConfUtil; |
| import org.apache.tinkerpop.gremlin.process.computer.GraphFilter; |
| import org.apache.tinkerpop.gremlin.process.computer.util.VertexProgramHelper; |
| import org.apache.tinkerpop.gremlin.structure.util.star.StarGraph; |
| |
| import java.io.IOException; |
| import java.util.Optional; |
| |
| /** |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| */ |
| public final class GraphFilterRecordReader extends RecordReader<NullWritable, VertexWritable> { |
| |
| private GraphFilter graphFilter = null; |
| private RecordReader<NullWritable, VertexWritable> recordReader; |
| |
| public GraphFilterRecordReader() { |
| } |
| |
| @Override |
| public void initialize(final InputSplit inputSplit, final TaskAttemptContext taskAttemptContext) throws IOException, InterruptedException { |
| final Configuration configuration = taskAttemptContext.getConfiguration(); |
| final InputFormat<NullWritable, VertexWritable> inputFormat = ReflectionUtils.newInstance(configuration.getClass(Constants.GREMLIN_HADOOP_GRAPH_READER, InputFormat.class, InputFormat.class), configuration); |
| if (!(inputFormat instanceof GraphFilterAware) && configuration.get(Constants.GREMLIN_HADOOP_GRAPH_FILTER, null) != null) |
| this.graphFilter = VertexProgramHelper.deserialize(ConfUtil.makeApacheConfiguration(configuration), Constants.GREMLIN_HADOOP_GRAPH_FILTER); |
| this.recordReader = inputFormat.createRecordReader(inputSplit, taskAttemptContext); |
| this.recordReader.initialize(inputSplit, taskAttemptContext); |
| } |
| |
| @Override |
| public boolean nextKeyValue() throws IOException, InterruptedException { |
| if (null == this.graphFilter) { |
| return this.recordReader.nextKeyValue(); |
| } else { |
| while (true) { |
| if (this.recordReader.nextKeyValue()) { |
| final VertexWritable vertexWritable = this.recordReader.getCurrentValue(); |
| final Optional<StarGraph.StarVertex> vertex = vertexWritable.get().applyGraphFilter(this.graphFilter); |
| if (vertex.isPresent()) { |
| vertexWritable.set(vertex.get()); |
| return true; |
| } |
| } else { |
| return false; |
| } |
| } |
| } |
| } |
| |
| @Override |
| public NullWritable getCurrentKey() throws IOException, InterruptedException { |
| return NullWritable.get(); |
| } |
| |
| @Override |
| public VertexWritable getCurrentValue() throws IOException, InterruptedException { |
| return this.recordReader.getCurrentValue(); |
| } |
| |
| @Override |
| public float getProgress() throws IOException, InterruptedException { |
| return this.recordReader.getProgress(); |
| } |
| |
| @Override |
| public void close() throws IOException { |
| this.recordReader.close(); |
| } |
| } |