/*

  * 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.examples;

 import org.apache.giraph.bsp.BspInputSplit;

 import org.apache.giraph.conf.BooleanConfOption;

 import org.apache.giraph.conf.LongConfOption;

 import org.apache.giraph.io.VertexReader;

 import org.apache.hadoop.io.Writable;

 import org.apache.hadoop.io.WritableComparable;

 import org.apache.hadoop.mapreduce.InputSplit;

 import org.apache.hadoop.mapreduce.TaskAttemptContext;

 import java.io.IOException;

 /**

  * Used by GeneratedVertexInputFormat to read some generated data

  *

  * @param <I> Vertex index value

  * @param <V> Vertex value

  * @param <E> Edge value

  */

 @SuppressWarnings("rawtypes")

 public abstract class GeneratedVertexReader<

     I extends WritableComparable, V extends Writable,

     E extends Writable>

     extends VertexReader<I, V, E> {

   /** Vertices produced by this reader */

   public static final LongConfOption READER_VERTICES =

       new LongConfOption("GeneratedVertexReader.reader_vertices", 10,

           "Vertices produced by this reader");

   /** Reverse the order of the vertices? */

   public static final BooleanConfOption REVERSE_ID_ORDER =

       new BooleanConfOption("GeneratedVertexReader.reverseIdOrder", false,

           "Reverse the order of the vertices?");

   /** Records read so far */

   protected long recordsRead = 0;

   /** Total records to read (on this split alone) */

   protected long totalRecords = 0;

   /** The input split from initialize(). */

   protected BspInputSplit inputSplit = null;

   /** Reverse the id order? */

   protected boolean reverseIdOrder;

   /**

    * Default constructor for reflection.

    */

   public GeneratedVertexReader() {

   }

   @Override

   public final void initialize(InputSplit inputSplit,

       TaskAttemptContext context) throws IOException {

     totalRecords = GeneratedVertexReader.READER_VERTICES.get(getConf());

     reverseIdOrder = GeneratedVertexReader.REVERSE_ID_ORDER.get(getConf());

     this.inputSplit = (BspInputSplit) inputSplit;

   }

   @Override

   public void close() throws IOException {

   }

   @Override

   public final float getProgress() throws IOException {

     return recordsRead * 100.0f / totalRecords;

   }

 }