/*

  * 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.io.internal;

 import org.apache.giraph.io.EdgeInputFormat;

 import org.apache.giraph.io.EdgeReader;

 import org.apache.giraph.job.HadoopUtils;

 import org.apache.hadoop.conf.Configuration;

 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.TaskAttemptContext;

 import java.io.DataInput;

 import java.io.DataOutput;

 import java.io.IOException;

 import java.util.List;

 /**

  * For internal use only.

  *

  * Wraps user set {@link EdgeInputFormat} to make sure proper configuration

  * parameters are passed around, that user can set parameters in

  * configuration and they will be available in other methods related to this

  * format.

  *

  * @param <I> Vertex id

  * @param <E> Edge data

  */

 public class WrappedEdgeInputFormat<I extends WritableComparable,

     E extends Writable> extends EdgeInputFormat<I, E> {

   /** {@link EdgeInputFormat} which is wrapped */

   private EdgeInputFormat<I, E> originalInputFormat;

   /**

    * Constructor

    *

    * @param edgeInputFormat Edge input format to wrap

    */

   public WrappedEdgeInputFormat(

       EdgeInputFormat<I, E> edgeInputFormat) {

     originalInputFormat = edgeInputFormat;

   }

   @Override

   public void checkInputSpecs(Configuration conf) {

     originalInputFormat.checkInputSpecs(getConf());

   }

   @Override

   public List<InputSplit> getSplits(JobContext context,

       int minSplitCountHint) throws IOException, InterruptedException {

     return originalInputFormat.getSplits(

         HadoopUtils.makeJobContext(getConf(), context),

         minSplitCountHint);

   }

   @Override

   public EdgeReader<I, E> createEdgeReader(InputSplit split,

       TaskAttemptContext context) throws IOException {

     EdgeReader<I, E> edgeReader =

         originalInputFormat.createEdgeReader(split,

             HadoopUtils.makeTaskAttemptContext(getConf(), context));

     return new WrappedEdgeReader<I, E>(edgeReader, getConf());

   }

   @Override

   public void writeInputSplit(InputSplit inputSplit,

       DataOutput dataOutput) throws IOException {

     originalInputFormat.writeInputSplit(inputSplit, dataOutput);

   }

   @Override

   public InputSplit readInputSplit(

       DataInput dataInput) throws IOException, ClassNotFoundException {

     return originalInputFormat.readInputSplit(dataInput);

   }

 }