/*
* 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.giraph.hive.input.vertex;
import com.facebook.giraph.hive.input.HiveApiInputFormat;
import com.facebook.giraph.hive.record.HiveReadableRecord;
import java.io.IOException;
import java.util.List;
import org.apache.giraph.hive.common.HiveProfiles;
import org.apache.giraph.io.VertexInputFormat;
import org.apache.giraph.io.VertexReader;
import org.apache.giraph.io.iterables.VertexReaderWrapper;
import org.apache.hadoop.io.Writable;
import org.apache.hadoop.io.WritableComparable;
import org.apache.hadoop.mapreduce.InputSplit;
import org.apache.hadoop.mapreduce.JobContext;
import org.apache.hadoop.mapreduce.RecordReader;
import org.apache.hadoop.mapreduce.TaskAttemptContext;
/**
* {@link VertexInputFormat} for reading vertices from Hive.
*
* @param <I> Vertex id
* @param <V> Vertex value
* @param <E> Edge value
*/
public class HiveVertexInputFormat<I extends WritableComparable,
V extends Writable, E extends Writable>
extends VertexInputFormat<I, V, E> {
/** Underlying Hive InputFormat used */
private final HiveApiInputFormat hiveInputFormat;
/**
* Create vertex input format
*/
public HiveVertexInputFormat() {
hiveInputFormat = new HiveApiInputFormat();
hiveInputFormat.setMyProfileId(HiveProfiles.VERTEX_INPUT_PROFILE_ID);
}
@Override
public List<InputSplit> getSplits(JobContext context, int minSplitCountHint)
throws IOException, InterruptedException {
return hiveInputFormat.getSplits(context);
}
@Override
public VertexReader<I, V, E> createVertexReader(InputSplit split,
TaskAttemptContext context) throws IOException {
HiveVertexReader<I, V, E> reader = new HiveVertexReader<I, V, E>();
reader.setTableSchema(hiveInputFormat.getTableSchema(getConf()));
RecordReader<WritableComparable, HiveReadableRecord> baseReader;
try {
baseReader = hiveInputFormat.createRecordReader(split, context);
} catch (InterruptedException e) {
throw new IOException("Could not create vertex reader", e);
}
reader.setHiveRecordReader(baseReader);
return new VertexReaderWrapper<I, V, E>(reader);
}
}