| /* |
| * 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.JobContext; |
| 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.process.computer.GraphFilter; |
| |
| import java.io.IOException; |
| import java.util.List; |
| |
| /** |
| * GraphFilterInputFormat is a utility {@link InputFormat} that is useful if the underlying InputFormat is not {@link GraphFilterAware}. |
| * If the underlying InputFormat is GraphFilterAware, then GraphFilterInputFormat acts as an identity mapping. |
| * If the underlying InputFormat is not GraphFilterAware, then GraphFilterInputFormat will apply the respective {@link GraphFilter} |
| * and prune the loaded source graph data accordingly. |
| * |
| * @author Marko A. Rodriguez (http://markorodriguez.com) |
| */ |
| public final class GraphFilterInputFormat extends InputFormat<NullWritable, VertexWritable> implements GraphFilterAware { |
| |
| @Override |
| public List<InputSplit> getSplits(final JobContext jobContext) throws IOException, InterruptedException { |
| final Configuration configuration = jobContext.getConfiguration(); |
| return ReflectionUtils.newInstance(configuration.getClass(Constants.GREMLIN_HADOOP_GRAPH_READER, InputFormat.class, InputFormat.class), configuration).getSplits(jobContext); |
| } |
| |
| @Override |
| public RecordReader<NullWritable, VertexWritable> createRecordReader(final InputSplit inputSplit, final TaskAttemptContext taskAttemptContext) throws IOException, InterruptedException { |
| return new GraphFilterRecordReader(); |
| } |
| |
| @Override |
| public void setGraphFilter(final GraphFilter graphFilter) { |
| // do nothing -- loaded via configuration |
| } |
| } |